* [PATCH 01/17] parisc: Remove unused symbol vdso_data
2024-12-16 14:09 [PATCH 00/17] vDSO: Introduce generic data storage Thomas Weißschuh
@ 2024-12-16 14:09 ` Thomas Weißschuh
2024-12-16 14:09 ` [PATCH 02/17] vdso: Introduce vdso/align.h Thomas Weißschuh
` (15 subsequent siblings)
16 siblings, 0 replies; 29+ messages in thread
From: Thomas Weißschuh @ 2024-12-16 14:09 UTC (permalink / raw)
To: James E.J. Bottomley, Helge Deller, Andy Lutomirski,
Thomas Gleixner, Vincenzo Frascino, Anna-Maria Behnsen,
Frederic Weisbecker, Andrew Morton, Catalin Marinas, Will Deacon,
Theodore Ts'o, Jason A. Donenfeld, Paul Walmsley,
Palmer Dabbelt, Albert Ou, Huacai Chen, WANG Xuerui, Russell King,
Heiko Carstens, Vasily Gorbik, Alexander Gordeev,
Christian Borntraeger, Sven Schnelle, Thomas Bogendoerfer,
Michael Ellerman, Nicholas Piggin, Christophe Leroy, Naveen N Rao,
Madhavan Srinivasan, Ingo Molnar, Borislav Petkov, Dave Hansen,
x86, H. Peter Anvin, Arnd Bergmann
Cc: linux-parisc, linux-kernel, linux-arm-kernel, linux-riscv,
loongarch, linux-s390, linux-mips, linuxppc-dev, linux-arch,
Nam Cao, Thomas Weißschuh
The symbol vdso_data is and has been unused.
Remove it.
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
---
arch/parisc/include/asm/vdso.h | 2 --
1 file changed, 2 deletions(-)
diff --git a/arch/parisc/include/asm/vdso.h b/arch/parisc/include/asm/vdso.h
index 2a2dc11b5545fc642a7ae4596dc174111433e948..5f581c1d64606b3ec8f9967efe31dd3d551adf76 100644
--- a/arch/parisc/include/asm/vdso.h
+++ b/arch/parisc/include/asm/vdso.h
@@ -12,8 +12,6 @@
#define VDSO64_SYMBOL(tsk, name) ((tsk)->mm->context.vdso_base + (vdso64_offset_##name))
#define VDSO32_SYMBOL(tsk, name) ((tsk)->mm->context.vdso_base + (vdso32_offset_##name))
-extern struct vdso_data *vdso_data;
-
#endif /* __ASSEMBLY __ */
/* Default link addresses for the vDSOs */
--
2.47.1
^ permalink raw reply related [flat|nested] 29+ messages in thread* [PATCH 02/17] vdso: Introduce vdso/align.h
2024-12-16 14:09 [PATCH 00/17] vDSO: Introduce generic data storage Thomas Weißschuh
2024-12-16 14:09 ` [PATCH 01/17] parisc: Remove unused symbol vdso_data Thomas Weißschuh
@ 2024-12-16 14:09 ` Thomas Weißschuh
2024-12-16 14:09 ` [PATCH 03/17] vdso: Add generic time data storage Thomas Weißschuh
` (14 subsequent siblings)
16 siblings, 0 replies; 29+ messages in thread
From: Thomas Weißschuh @ 2024-12-16 14:09 UTC (permalink / raw)
To: James E.J. Bottomley, Helge Deller, Andy Lutomirski,
Thomas Gleixner, Vincenzo Frascino, Anna-Maria Behnsen,
Frederic Weisbecker, Andrew Morton, Catalin Marinas, Will Deacon,
Theodore Ts'o, Jason A. Donenfeld, Paul Walmsley,
Palmer Dabbelt, Albert Ou, Huacai Chen, WANG Xuerui, Russell King,
Heiko Carstens, Vasily Gorbik, Alexander Gordeev,
Christian Borntraeger, Sven Schnelle, Thomas Bogendoerfer,
Michael Ellerman, Nicholas Piggin, Christophe Leroy, Naveen N Rao,
Madhavan Srinivasan, Ingo Molnar, Borislav Petkov, Dave Hansen,
x86, H. Peter Anvin, Arnd Bergmann
Cc: linux-parisc, linux-kernel, linux-arm-kernel, linux-riscv,
loongarch, linux-s390, linux-mips, linuxppc-dev, linux-arch,
Nam Cao, Thomas Weißschuh
The vDSO implementation can only include headers from the vdso/
namespace. To enable the usage of the ALIGN() macro from the vDSO, move
linux/align.h to vdso/align.h wholly.
As the only dependency linux/const.h is only a wrapper around
vdso/const.h anyways adapt that dependency.
Also provide a compatibility wrapper linux/align.h.
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
---
include/linux/align.h | 10 +---------
include/vdso/align.h | 15 +++++++++++++++
2 files changed, 16 insertions(+), 9 deletions(-)
diff --git a/include/linux/align.h b/include/linux/align.h
index 2b4acec7b95a27b6768d48f46519abc584c94d5d..55debf105a5d610c592e5c53a4153018ea1ae2c6 100644
--- a/include/linux/align.h
+++ b/include/linux/align.h
@@ -2,14 +2,6 @@
#ifndef _LINUX_ALIGN_H
#define _LINUX_ALIGN_H
-#include <linux/const.h>
-
-/* @a is a power of 2 value */
-#define ALIGN(x, a) __ALIGN_KERNEL((x), (a))
-#define ALIGN_DOWN(x, a) __ALIGN_KERNEL((x) - ((a) - 1), (a))
-#define __ALIGN_MASK(x, mask) __ALIGN_KERNEL_MASK((x), (mask))
-#define PTR_ALIGN(p, a) ((typeof(p))ALIGN((unsigned long)(p), (a)))
-#define PTR_ALIGN_DOWN(p, a) ((typeof(p))ALIGN_DOWN((unsigned long)(p), (a)))
-#define IS_ALIGNED(x, a) (((x) & ((typeof(x))(a) - 1)) == 0)
+#include <vdso/align.h>
#endif /* _LINUX_ALIGN_H */
diff --git a/include/vdso/align.h b/include/vdso/align.h
new file mode 100644
index 0000000000000000000000000000000000000000..02dd8626b5c5aa59d2ee0b15799b6e9adb343f65
--- /dev/null
+++ b/include/vdso/align.h
@@ -0,0 +1,15 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __VDSO_ALIGN_H
+#define __VDSO_ALIGN_H
+
+#include <vdso/const.h>
+
+/* @a is a power of 2 value */
+#define ALIGN(x, a) __ALIGN_KERNEL((x), (a))
+#define ALIGN_DOWN(x, a) __ALIGN_KERNEL((x) - ((a) - 1), (a))
+#define __ALIGN_MASK(x, mask) __ALIGN_KERNEL_MASK((x), (mask))
+#define PTR_ALIGN(p, a) ((typeof(p))ALIGN((unsigned long)(p), (a)))
+#define PTR_ALIGN_DOWN(p, a) ((typeof(p))ALIGN_DOWN((unsigned long)(p), (a)))
+#define IS_ALIGNED(x, a) (((x) & ((typeof(x))(a) - 1)) == 0)
+
+#endif /* __VDSO_ALIGN_H */
--
2.47.1
^ permalink raw reply related [flat|nested] 29+ messages in thread* [PATCH 03/17] vdso: Add generic time data storage
2024-12-16 14:09 [PATCH 00/17] vDSO: Introduce generic data storage Thomas Weißschuh
2024-12-16 14:09 ` [PATCH 01/17] parisc: Remove unused symbol vdso_data Thomas Weißschuh
2024-12-16 14:09 ` [PATCH 02/17] vdso: Introduce vdso/align.h Thomas Weißschuh
@ 2024-12-16 14:09 ` Thomas Weißschuh
2024-12-18 7:32 ` Christophe Leroy
2024-12-16 14:10 ` [PATCH 04/17] vdso: Add generic random " Thomas Weißschuh
` (13 subsequent siblings)
16 siblings, 1 reply; 29+ messages in thread
From: Thomas Weißschuh @ 2024-12-16 14:09 UTC (permalink / raw)
To: James E.J. Bottomley, Helge Deller, Andy Lutomirski,
Thomas Gleixner, Vincenzo Frascino, Anna-Maria Behnsen,
Frederic Weisbecker, Andrew Morton, Catalin Marinas, Will Deacon,
Theodore Ts'o, Jason A. Donenfeld, Paul Walmsley,
Palmer Dabbelt, Albert Ou, Huacai Chen, WANG Xuerui, Russell King,
Heiko Carstens, Vasily Gorbik, Alexander Gordeev,
Christian Borntraeger, Sven Schnelle, Thomas Bogendoerfer,
Michael Ellerman, Nicholas Piggin, Christophe Leroy, Naveen N Rao,
Madhavan Srinivasan, Ingo Molnar, Borislav Petkov, Dave Hansen,
x86, H. Peter Anvin, Arnd Bergmann
Cc: linux-parisc, linux-kernel, linux-arm-kernel, linux-riscv,
loongarch, linux-s390, linux-mips, linuxppc-dev, linux-arch,
Nam Cao, Thomas Weißschuh
Historically each architecture defined their own way to store the vDSO
data page. Add a generic mechanism to provide storage for that page.
Furthermore this generic storage will be extended to also provide
uniform storage for *non*-time-related data, like the random state or
architecture-specific data. These will have their own pages and data
structures, so rename 'vdso_data' into 'vdso_time_data' to make that
split clear from the name.
Also introduce a new consistent naming scheme for the symbols related to
the vDSO, which makes it clear if the symbol is accessible from
userspace or kernel space and the type of data behind the symbol.
The generic fault handler contains an optimization to prefault the vvar
page when the timens page is accessed. This was lifted from s390 and x86.
Co-developed-by: Nam Cao <namcao@linutronix.de>
Signed-off-by: Nam Cao <namcao@linutronix.de>
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
---
MAINTAINERS | 1 +
include/linux/time_namespace.h | 1 +
include/linux/vdso_datastore.h | 10 +++++
include/vdso/datapage.h | 69 +++++++++++++++++++++++++----
lib/Kconfig | 1 +
lib/Makefile | 2 +
lib/vdso_kernel/Kconfig | 7 +++
lib/vdso_kernel/Makefile | 3 ++
lib/vdso_kernel/datastore.c | 99 ++++++++++++++++++++++++++++++++++++++++++
9 files changed, 185 insertions(+), 8 deletions(-)
diff --git a/MAINTAINERS b/MAINTAINERS
index 1e930c7a58b13d8bbe6bf133ba7b36aa24c2b5e0..9d947e1e90ff3c6060e56f3b7eaa28cd60d6191c 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -9677,6 +9677,7 @@ F: include/asm-generic/vdso/vsyscall.h
F: include/vdso/
F: kernel/time/vsyscall.c
F: lib/vdso/
+F: lib/vdso_kernel/
GENWQE (IBM Generic Workqueue Card)
M: Frank Haverkamp <haver@linux.ibm.com>
diff --git a/include/linux/time_namespace.h b/include/linux/time_namespace.h
index 876e31b4461d0ee01fe2bd3d136acdea2611789f..4b81db223f5450218dfaf553b24195be9ba97c08 100644
--- a/include/linux/time_namespace.h
+++ b/include/linux/time_namespace.h
@@ -8,6 +8,7 @@
#include <linux/ns_common.h>
#include <linux/err.h>
#include <linux/time64.h>
+#include <vdso/datapage.h>
struct user_namespace;
extern struct user_namespace init_user_ns;
diff --git a/include/linux/vdso_datastore.h b/include/linux/vdso_datastore.h
new file mode 100644
index 0000000000000000000000000000000000000000..a91fa24b06e09321fdff8c2c7bdfbc1b206db574
--- /dev/null
+++ b/include/linux/vdso_datastore.h
@@ -0,0 +1,10 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _LINUX_VDSO_DATASTORE_H
+#define _LINUX_VDSO_DATASTORE_H
+
+#include <linux/mm_types.h>
+
+extern const struct vm_special_mapping vdso_vvar_mapping;
+struct vm_area_struct *vdso_install_vvar_mapping(struct mm_struct *mm, unsigned long addr);
+
+#endif /* _LINUX_VDSO_DATASTORE_H */
diff --git a/include/vdso/datapage.h b/include/vdso/datapage.h
index d967baa0cd0c65784e38dc4fcd7b9e8273923947..69af424413db1f265607d0f1bdbf88550548c5ba 100644
--- a/include/vdso/datapage.h
+++ b/include/vdso/datapage.h
@@ -45,11 +45,11 @@ struct arch_vdso_time_data {};
*
* There is one vdso_timestamp object in vvar for each vDSO-accelerated
* clock_id. For high-resolution clocks, this encodes the time
- * corresponding to vdso_data.cycle_last. For coarse clocks this encodes
+ * corresponding to vdso_time_data.cycle_last. For coarse clocks this encodes
* the actual time.
*
* To be noticed that for highres clocks nsec is left-shifted by
- * vdso_data.cs[x].shift.
+ * vdso_time_data[x].shift.
*/
struct vdso_timestamp {
u64 sec;
@@ -57,7 +57,7 @@ struct vdso_timestamp {
};
/**
- * struct vdso_data - vdso datapage representation
+ * struct vdso_time_data - vdso datapage representation
* @seq: timebase sequence counter
* @clock_mode: clock mode
* @cycle_last: timebase at clocksource init
@@ -74,7 +74,7 @@ struct vdso_timestamp {
* @arch_data: architecture specific data (optional, defaults
* to an empty struct)
*
- * vdso_data will be accessed by 64 bit and compat code at the same time
+ * vdso_time_data will be accessed by 64 bit and compat code at the same time
* so we should be careful before modifying this structure.
*
* The ordering of the struct members is optimized to have fast access to the
@@ -92,7 +92,7 @@ struct vdso_timestamp {
* For clocks which are not affected by time namespace adjustment the
* offset must be zero.
*/
-struct vdso_data {
+struct vdso_time_data {
u32 seq;
s32 clock_mode;
@@ -117,6 +117,8 @@ struct vdso_data {
struct arch_vdso_time_data arch_data;
};
+#define vdso_data vdso_time_data
+
/**
* struct vdso_rng_data - vdso RNG state information
* @generation: counter representing the number of RNG reseeds
@@ -136,18 +138,55 @@ struct vdso_rng_data {
* With the hidden visibility, the compiler simply generates a PC-relative
* relocation, and this is what we need.
*/
-extern struct vdso_data _vdso_data[CS_BASES] __attribute__((visibility("hidden")));
-extern struct vdso_data _timens_data[CS_BASES] __attribute__((visibility("hidden")));
+#ifndef CONFIG_GENERIC_VDSO_DATA_STORE
+extern struct vdso_time_data _vdso_data[CS_BASES] __attribute__((visibility("hidden")));
+extern struct vdso_time_data _timens_data[CS_BASES] __attribute__((visibility("hidden")));
extern struct vdso_rng_data _vdso_rng_data __attribute__((visibility("hidden")));
+#else
+extern const struct vdso_time_data vdso_u_time_data[CS_BASES] __attribute__((visibility("hidden")));
+extern const struct vdso_time_data vdso_u_timens_data[CS_BASES] __attribute__((visibility("hidden")));
+
+extern struct vdso_time_data *vdso_k_time_data;
+#endif
/**
* union vdso_data_store - Generic vDSO data page
*/
union vdso_data_store {
- struct vdso_data data[CS_BASES];
+ struct vdso_time_data data[CS_BASES];
u8 page[1U << CONFIG_PAGE_SHIFT];
};
+#ifdef CONFIG_GENERIC_VDSO_DATA_STORE
+
+enum vdso_pages {
+ VDSO_TIME_PAGE_OFFSET,
+ VDSO_TIMENS_PAGE_OFFSET,
+ VDSO_NR_PAGES
+};
+
+static __always_inline struct vdso_time_data *__arch_get_vdso_k_time_data(void)
+{
+ return vdso_k_time_data;
+}
+#define __arch_get_k_vdso_data __arch_get_vdso_k_time_data
+
+static __always_inline const struct vdso_time_data *__arch_get_vdso_u_time_data(void)
+{
+ return vdso_u_time_data;
+}
+#define __arch_get_vdso_data __arch_get_vdso_u_time_data
+
+#ifdef CONFIG_TIME_NS
+static __always_inline const struct vdso_time_data *__arch_get_vdso_u_timens_data(void)
+{
+ return vdso_u_timens_data;
+}
+#define __arch_get_timens_vdso_data(vd) __arch_get_vdso_u_timens_data()
+#endif /* CONFIG_TIME_NS */
+
+#endif /* CONFIG_GENERIC_VDSO_DATA_STORE */
+
/*
* The generic vDSO implementation requires that gettimeofday.h
* provides:
@@ -164,6 +203,20 @@ union vdso_data_store {
#include <asm/vdso/gettimeofday.h>
#endif /* ENABLE_COMPAT_VDSO */
+#else /* !__ASSEMBLY__ */
+
+#ifdef CONFIG_TIME_NS
+#define __vdso_u_timens_data PROVIDE(vdso_u_timens_data = vdso_u_data + PAGE_SIZE);
+#else
+#define __vdso_u_timens_data
+#endif
+
+#define VDSO_VVAR_SYMS \
+ PROVIDE(vdso_u_data = . - __VDSO_PAGES * PAGE_SIZE); \
+ PROVIDE(vdso_u_time_data = vdso_u_data); \
+ __vdso_u_timens_data \
+
+
#endif /* !__ASSEMBLY__ */
#endif /* __VDSO_DATAPAGE_H */
diff --git a/lib/Kconfig b/lib/Kconfig
index 5a318f753b2f44cb0a7905cc0092e81c133bc112..7d59b2c10ce5ffab03378ead254d9f9017a4482f 100644
--- a/lib/Kconfig
+++ b/lib/Kconfig
@@ -659,6 +659,7 @@ config UCS2_STRING
# generic vdso
#
source "lib/vdso/Kconfig"
+source "lib/vdso_kernel/Kconfig"
source "lib/fonts/Kconfig"
diff --git a/lib/Makefile b/lib/Makefile
index a8155c972f02856fcc61ee949ddda436cfe211ff..aeedeea86b26cee50d7ced18f9b77b3c51201930 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -401,3 +401,5 @@ obj-$(CONFIG_GENERIC_LIB_DEVMEM_IS_ALLOWED) += devmem_is_allowed.o
obj-$(CONFIG_FIRMWARE_TABLE) += fw_table.o
subdir-$(CONFIG_FORTIFY_SOURCE) += test_fortify
+
+obj-y += vdso_kernel/
diff --git a/lib/vdso_kernel/Kconfig b/lib/vdso_kernel/Kconfig
new file mode 100644
index 0000000000000000000000000000000000000000..0c7ade9b3ece67c0c0ca892544b9e29e53c860c4
--- /dev/null
+++ b/lib/vdso_kernel/Kconfig
@@ -0,0 +1,7 @@
+# SPDX-License-Identifier: GPL-2.0
+
+config GENERIC_VDSO_DATA_STORE
+ bool
+ depends on HAVE_GENERIC_VDSO
+ help
+ Selected by architectures that use the generic vDSO data store.
diff --git a/lib/vdso_kernel/Makefile b/lib/vdso_kernel/Makefile
new file mode 100644
index 0000000000000000000000000000000000000000..4826e49f9edbdb48506b50957584ed89bde5f37f
--- /dev/null
+++ b/lib/vdso_kernel/Makefile
@@ -0,0 +1,3 @@
+# SPDX-License-Identifier: GPL-2.0
+
+obj-$(CONFIG_GENERIC_VDSO_DATA_STORE) += datastore.o
diff --git a/lib/vdso_kernel/datastore.c b/lib/vdso_kernel/datastore.c
new file mode 100644
index 0000000000000000000000000000000000000000..c9cd269b1ed1b6cdd5fdf9fe929d0b778314b962
--- /dev/null
+++ b/lib/vdso_kernel/datastore.c
@@ -0,0 +1,99 @@
+// SPDX-License-Identifier: GPL-2.0-only
+
+#include <linux/linkage.h>
+#include <linux/mmap_lock.h>
+#include <linux/mm.h>
+#include <linux/time_namespace.h>
+#include <linux/types.h>
+#include <linux/vdso_datastore.h>
+#include <vdso/datapage.h>
+
+/*
+ * The vDSO data page.
+ */
+static union vdso_data_store vdso_time_data_store __page_aligned_data;
+struct vdso_time_data *vdso_k_time_data = vdso_time_data_store.data;
+static_assert(sizeof(vdso_time_data_store) == PAGE_SIZE);
+
+static vm_fault_t vvar_fault(const struct vm_special_mapping *sm,
+ struct vm_area_struct *vma, struct vm_fault *vmf)
+{
+ struct page *timens_page = find_timens_vvar_page(vma);
+ unsigned long addr, pfn;
+ vm_fault_t err;
+
+ switch (vmf->pgoff) {
+ case VDSO_TIME_PAGE_OFFSET:
+ pfn = __phys_to_pfn(__pa_symbol(vdso_k_time_data));
+ if (timens_page) {
+ /*
+ * Fault in VVAR page too, since it will be accessed
+ * to get clock data anyway.
+ */
+ addr = vmf->address + VDSO_TIMENS_PAGE_OFFSET * PAGE_SIZE;
+ err = vmf_insert_pfn(vma, addr, pfn);
+ if (unlikely(err & VM_FAULT_ERROR))
+ return err;
+ pfn = page_to_pfn(timens_page);
+ }
+ break;
+ case VDSO_TIMENS_PAGE_OFFSET:
+ /*
+ * If a task belongs to a time namespace then a namespace
+ * specific VVAR is mapped with the VVAR_DATA_PAGE_OFFSET and
+ * the real VVAR page is mapped with the VVAR_TIMENS_PAGE_OFFSET
+ * offset.
+ * See also the comment near timens_setup_vdso_data().
+ */
+ if (!IS_ENABLED(CONFIG_TIME_NS) || !timens_page)
+ return VM_FAULT_SIGBUS;
+ pfn = __phys_to_pfn(__pa_symbol(vdso_k_time_data));
+ break;
+ default:
+ return VM_FAULT_SIGBUS;
+ }
+
+ return vmf_insert_pfn(vma, vmf->address, pfn);
+}
+
+const struct vm_special_mapping vdso_vvar_mapping = {
+ .name = "[vvar]",
+ .fault = vvar_fault,
+};
+
+struct vm_area_struct *vdso_install_vvar_mapping(struct mm_struct *mm, unsigned long addr)
+{
+ return _install_special_mapping(mm, addr, VDSO_NR_PAGES * PAGE_SIZE,
+ VM_READ | VM_MAYREAD | VM_IO | VM_DONTDUMP | VM_PFNMAP,
+ &vdso_vvar_mapping);
+}
+
+#ifdef CONFIG_TIME_NS
+/*
+ * The vvar page layout depends on whether a task belongs to the root or
+ * non-root time namespace. Whenever a task changes its namespace, the VVAR
+ * page tables are cleared and then they will be re-faulted with a
+ * corresponding layout.
+ * See also the comment near timens_setup_vdso_data() for details.
+ */
+int vdso_join_timens(struct task_struct *task, struct time_namespace *ns)
+{
+ struct mm_struct *mm = task->mm;
+ struct vm_area_struct *vma;
+ VMA_ITERATOR(vmi, mm, 0);
+
+ mmap_read_lock(mm);
+ for_each_vma(vmi, vma) {
+ if (vma_is_special_mapping(vma, &vdso_vvar_mapping))
+ zap_vma_pages(vma);
+ }
+ mmap_read_unlock(mm);
+
+ return 0;
+}
+#endif
+
+struct vdso_time_data *arch_get_vdso_data(void *vvar_page)
+{
+ return (struct vdso_time_data *)vvar_page;
+}
--
2.47.1
^ permalink raw reply related [flat|nested] 29+ messages in thread* Re: [PATCH 03/17] vdso: Add generic time data storage
2024-12-16 14:09 ` [PATCH 03/17] vdso: Add generic time data storage Thomas Weißschuh
@ 2024-12-18 7:32 ` Christophe Leroy
2024-12-18 10:25 ` Thomas Weißschuh
0 siblings, 1 reply; 29+ messages in thread
From: Christophe Leroy @ 2024-12-18 7:32 UTC (permalink / raw)
To: Thomas Weißschuh, James E.J. Bottomley, Helge Deller,
Andy Lutomirski, Thomas Gleixner, Vincenzo Frascino,
Anna-Maria Behnsen, Frederic Weisbecker, Andrew Morton,
Catalin Marinas, Will Deacon, Theodore Ts'o,
Jason A. Donenfeld, Paul Walmsley, Palmer Dabbelt, Albert Ou,
Huacai Chen, WANG Xuerui, Russell King, Heiko Carstens,
Vasily Gorbik, Alexander Gordeev, Christian Borntraeger,
Sven Schnelle, Thomas Bogendoerfer, Michael Ellerman,
Nicholas Piggin, Naveen N Rao, Madhavan Srinivasan, Ingo Molnar,
Borislav Petkov, Dave Hansen, x86, H. Peter Anvin, Arnd Bergmann
Cc: linux-parisc, linux-kernel, linux-arm-kernel, linux-riscv,
loongarch, linux-s390, linux-mips, linuxppc-dev, linux-arch,
Nam Cao
Le 16/12/2024 à 15:09, Thomas Weißschuh a écrit :
> Historically each architecture defined their own way to store the vDSO
> data page. Add a generic mechanism to provide storage for that page.
>
> Furthermore this generic storage will be extended to also provide
> uniform storage for *non*-time-related data, like the random state or
> architecture-specific data. These will have their own pages and data
> structures, so rename 'vdso_data' into 'vdso_time_data' to make that
> split clear from the name.
>
> Also introduce a new consistent naming scheme for the symbols related to
> the vDSO, which makes it clear if the symbol is accessible from
> userspace or kernel space and the type of data behind the symbol.
>
> The generic fault handler contains an optimization to prefault the vvar
> page when the timens page is accessed. This was lifted from s390 and x86.
>
> Co-developed-by: Nam Cao <namcao@linutronix.de>
> Signed-off-by: Nam Cao <namcao@linutronix.de>
> Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
> ---
> MAINTAINERS | 1 +
> include/linux/time_namespace.h | 1 +
> include/linux/vdso_datastore.h | 10 +++++
> include/vdso/datapage.h | 69 +++++++++++++++++++++++++----
> lib/Kconfig | 1 +
> lib/Makefile | 2 +
> lib/vdso_kernel/Kconfig | 7 +++
> lib/vdso_kernel/Makefile | 3 ++
> lib/vdso_kernel/datastore.c | 99 ++++++++++++++++++++++++++++++++++++++++++
There is only one single file, namely datastore.c. You don't need a new
directory for that, I should go in lib/vdso/
> 9 files changed, 185 insertions(+), 8 deletions(-)
>
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 1e930c7a58b13d8bbe6bf133ba7b36aa24c2b5e0..9d947e1e90ff3c6060e56f3b7eaa28cd60d6191c 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -9677,6 +9677,7 @@ F: include/asm-generic/vdso/vsyscall.h
> F: include/vdso/
> F: kernel/time/vsyscall.c
> F: lib/vdso/
> +F: lib/vdso_kernel/
New dir not needed
>
> GENWQE (IBM Generic Workqueue Card)
> M: Frank Haverkamp <haver@linux.ibm.com>
> diff --git a/include/linux/time_namespace.h b/include/linux/time_namespace.h
> index 876e31b4461d0ee01fe2bd3d136acdea2611789f..4b81db223f5450218dfaf553b24195be9ba97c08 100644
> --- a/include/linux/time_namespace.h
> +++ b/include/linux/time_namespace.h
> @@ -8,6 +8,7 @@
> #include <linux/ns_common.h>
> #include <linux/err.h>
> #include <linux/time64.h>
> +#include <vdso/datapage.h>
>
> struct user_namespace;
> extern struct user_namespace init_user_ns;
> diff --git a/include/linux/vdso_datastore.h b/include/linux/vdso_datastore.h
> new file mode 100644
> index 0000000000000000000000000000000000000000..a91fa24b06e09321fdff8c2c7bdfbc1b206db574
> --- /dev/null
> +++ b/include/linux/vdso_datastore.h
> @@ -0,0 +1,10 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +#ifndef _LINUX_VDSO_DATASTORE_H
> +#define _LINUX_VDSO_DATASTORE_H
> +
> +#include <linux/mm_types.h>
> +
> +extern const struct vm_special_mapping vdso_vvar_mapping;
> +struct vm_area_struct *vdso_install_vvar_mapping(struct mm_struct *mm, unsigned long addr);
> +
> +#endif /* _LINUX_VDSO_DATASTORE_H */
> diff --git a/include/vdso/datapage.h b/include/vdso/datapage.h
> index d967baa0cd0c65784e38dc4fcd7b9e8273923947..69af424413db1f265607d0f1bdbf88550548c5ba 100644
> --- a/include/vdso/datapage.h
> +++ b/include/vdso/datapage.h
> @@ -45,11 +45,11 @@ struct arch_vdso_time_data {};
> *
> * There is one vdso_timestamp object in vvar for each vDSO-accelerated
> * clock_id. For high-resolution clocks, this encodes the time
> - * corresponding to vdso_data.cycle_last. For coarse clocks this encodes
> + * corresponding to vdso_time_data.cycle_last. For coarse clocks this encodes
> * the actual time.
> *
> * To be noticed that for highres clocks nsec is left-shifted by
> - * vdso_data.cs[x].shift.
> + * vdso_time_data[x].shift.
> */
> struct vdso_timestamp {
> u64 sec;
> @@ -57,7 +57,7 @@ struct vdso_timestamp {
> };
>
> /**
> - * struct vdso_data - vdso datapage representation
> + * struct vdso_time_data - vdso datapage representation
> * @seq: timebase sequence counter
> * @clock_mode: clock mode
> * @cycle_last: timebase at clocksource init
> @@ -74,7 +74,7 @@ struct vdso_timestamp {
> * @arch_data: architecture specific data (optional, defaults
> * to an empty struct)
> *
> - * vdso_data will be accessed by 64 bit and compat code at the same time
> + * vdso_time_data will be accessed by 64 bit and compat code at the same time
> * so we should be careful before modifying this structure.
> *
> * The ordering of the struct members is optimized to have fast access to the
> @@ -92,7 +92,7 @@ struct vdso_timestamp {
> * For clocks which are not affected by time namespace adjustment the
> * offset must be zero.
> */
> -struct vdso_data {
> +struct vdso_time_data {
> u32 seq;
>
> s32 clock_mode;
> @@ -117,6 +117,8 @@ struct vdso_data {
> struct arch_vdso_time_data arch_data;
> };
>
> +#define vdso_data vdso_time_data
> +
> /**
> * struct vdso_rng_data - vdso RNG state information
> * @generation: counter representing the number of RNG reseeds
> @@ -136,18 +138,55 @@ struct vdso_rng_data {
> * With the hidden visibility, the compiler simply generates a PC-relative
> * relocation, and this is what we need.
> */
> -extern struct vdso_data _vdso_data[CS_BASES] __attribute__((visibility("hidden")));
> -extern struct vdso_data _timens_data[CS_BASES] __attribute__((visibility("hidden")));
> +#ifndef CONFIG_GENERIC_VDSO_DATA_STORE
> +extern struct vdso_time_data _vdso_data[CS_BASES] __attribute__((visibility("hidden")));
> +extern struct vdso_time_data _timens_data[CS_BASES] __attribute__((visibility("hidden")));
> extern struct vdso_rng_data _vdso_rng_data __attribute__((visibility("hidden")));
> +#else
> +extern const struct vdso_time_data vdso_u_time_data[CS_BASES] __attribute__((visibility("hidden")));
> +extern const struct vdso_time_data vdso_u_timens_data[CS_BASES] __attribute__((visibility("hidden")));
> +
> +extern struct vdso_time_data *vdso_k_time_data;
> +#endif
>
> /**
> * union vdso_data_store - Generic vDSO data page
> */
> union vdso_data_store {
> - struct vdso_data data[CS_BASES];
> + struct vdso_time_data data[CS_BASES];
> u8 page[1U << CONFIG_PAGE_SHIFT];
> };
>
> +#ifdef CONFIG_GENERIC_VDSO_DATA_STORE
> +
> +enum vdso_pages {
> + VDSO_TIME_PAGE_OFFSET,
> + VDSO_TIMENS_PAGE_OFFSET,
> + VDSO_NR_PAGES
> +};
Naming that VDSO_ is confusing. Most macros called VDSO_ are related to
the VDSO Code. VDSO data related macros should be prefixed with VVAR_
> +
> +static __always_inline struct vdso_time_data *__arch_get_vdso_k_time_data(void)
> +{
> + return vdso_k_time_data;
> +}
> +#define __arch_get_k_vdso_data __arch_get_vdso_k_time_data
> +
> +static __always_inline const struct vdso_time_data *__arch_get_vdso_u_time_data(void)
> +{
> + return vdso_u_time_data;
> +}
> +#define __arch_get_vdso_data __arch_get_vdso_u_time_data
> +
> +#ifdef CONFIG_TIME_NS
> +static __always_inline const struct vdso_time_data *__arch_get_vdso_u_timens_data(void)
> +{
> + return vdso_u_timens_data;
> +}
> +#define __arch_get_timens_vdso_data(vd) __arch_get_vdso_u_timens_data()
> +#endif /* CONFIG_TIME_NS */
> +
> +#endif /* CONFIG_GENERIC_VDSO_DATA_STORE */
> +
> /*
> * The generic vDSO implementation requires that gettimeofday.h
> * provides:
> @@ -164,6 +203,20 @@ union vdso_data_store {
> #include <asm/vdso/gettimeofday.h>
> #endif /* ENABLE_COMPAT_VDSO */
>
> +#else /* !__ASSEMBLY__ */
> +
> +#ifdef CONFIG_TIME_NS
> +#define __vdso_u_timens_data PROVIDE(vdso_u_timens_data = vdso_u_data + PAGE_SIZE);
> +#else
> +#define __vdso_u_timens_data
> +#endif
> +
> +#define VDSO_VVAR_SYMS \
> + PROVIDE(vdso_u_data = . - __VDSO_PAGES * PAGE_SIZE); \
> + PROVIDE(vdso_u_time_data = vdso_u_data); \
> + __vdso_u_timens_data \
> +
> +
> #endif /* !__ASSEMBLY__ */
>
> #endif /* __VDSO_DATAPAGE_H */
> diff --git a/lib/Kconfig b/lib/Kconfig
> index 5a318f753b2f44cb0a7905cc0092e81c133bc112..7d59b2c10ce5ffab03378ead254d9f9017a4482f 100644
> --- a/lib/Kconfig
> +++ b/lib/Kconfig
> @@ -659,6 +659,7 @@ config UCS2_STRING
> # generic vdso
> #
> source "lib/vdso/Kconfig"
> +source "lib/vdso_kernel/Kconfig"
>
> source "lib/fonts/Kconfig"
>
> diff --git a/lib/Makefile b/lib/Makefile
> index a8155c972f02856fcc61ee949ddda436cfe211ff..aeedeea86b26cee50d7ced18f9b77b3c51201930 100644
> --- a/lib/Makefile
> +++ b/lib/Makefile
> @@ -401,3 +401,5 @@ obj-$(CONFIG_GENERIC_LIB_DEVMEM_IS_ALLOWED) += devmem_is_allowed.o
> obj-$(CONFIG_FIRMWARE_TABLE) += fw_table.o
>
> subdir-$(CONFIG_FORTIFY_SOURCE) += test_fortify
> +
> +obj-y += vdso_kernel/
No need for a new directory
> diff --git a/lib/vdso_kernel/Kconfig b/lib/vdso_kernel/Kconfig
> new file mode 100644
> index 0000000000000000000000000000000000000000..0c7ade9b3ece67c0c0ca892544b9e29e53c860c4
> --- /dev/null
> +++ b/lib/vdso_kernel/Kconfig
> @@ -0,0 +1,7 @@
> +# SPDX-License-Identifier: GPL-2.0
> +
> +config GENERIC_VDSO_DATA_STORE
> + bool
> + depends on HAVE_GENERIC_VDSO
> + help
> + Selected by architectures that use the generic vDSO data store.
> diff --git a/lib/vdso_kernel/Makefile b/lib/vdso_kernel/Makefile
> new file mode 100644
> index 0000000000000000000000000000000000000000..4826e49f9edbdb48506b50957584ed89bde5f37f
> --- /dev/null
> +++ b/lib/vdso_kernel/Makefile
> @@ -0,0 +1,3 @@
> +# SPDX-License-Identifier: GPL-2.0
> +
> +obj-$(CONFIG_GENERIC_VDSO_DATA_STORE) += datastore.o
> diff --git a/lib/vdso_kernel/datastore.c b/lib/vdso_kernel/datastore.c
> new file mode 100644
> index 0000000000000000000000000000000000000000..c9cd269b1ed1b6cdd5fdf9fe929d0b778314b962
> --- /dev/null
> +++ b/lib/vdso_kernel/datastore.c
> @@ -0,0 +1,99 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +
> +#include <linux/linkage.h>
> +#include <linux/mmap_lock.h>
> +#include <linux/mm.h>
> +#include <linux/time_namespace.h>
> +#include <linux/types.h>
> +#include <linux/vdso_datastore.h>
> +#include <vdso/datapage.h>
> +
> +/*
> + * The vDSO data page.
> + */
> +static union vdso_data_store vdso_time_data_store __page_aligned_data;
> +struct vdso_time_data *vdso_k_time_data = vdso_time_data_store.data;
> +static_assert(sizeof(vdso_time_data_store) == PAGE_SIZE);
> +
> +static vm_fault_t vvar_fault(const struct vm_special_mapping *sm,
> + struct vm_area_struct *vma, struct vm_fault *vmf)
> +{
> + struct page *timens_page = find_timens_vvar_page(vma);
> + unsigned long addr, pfn;
> + vm_fault_t err;
> +
> + switch (vmf->pgoff) {
> + case VDSO_TIME_PAGE_OFFSET:
> + pfn = __phys_to_pfn(__pa_symbol(vdso_k_time_data));
> + if (timens_page) {
> + /*
> + * Fault in VVAR page too, since it will be accessed
> + * to get clock data anyway.
> + */
> + addr = vmf->address + VDSO_TIMENS_PAGE_OFFSET * PAGE_SIZE;
> + err = vmf_insert_pfn(vma, addr, pfn);
> + if (unlikely(err & VM_FAULT_ERROR))
> + return err;
> + pfn = page_to_pfn(timens_page);
> + }
> + break;
> + case VDSO_TIMENS_PAGE_OFFSET:
> + /*
> + * If a task belongs to a time namespace then a namespace
> + * specific VVAR is mapped with the VVAR_DATA_PAGE_OFFSET and
> + * the real VVAR page is mapped with the VVAR_TIMENS_PAGE_OFFSET
> + * offset.
> + * See also the comment near timens_setup_vdso_data().
> + */
> + if (!IS_ENABLED(CONFIG_TIME_NS) || !timens_page)
> + return VM_FAULT_SIGBUS;
> + pfn = __phys_to_pfn(__pa_symbol(vdso_k_time_data));
> + break;
> + default:
> + return VM_FAULT_SIGBUS;
> + }
> +
> + return vmf_insert_pfn(vma, vmf->address, pfn);
> +}
> +
> +const struct vm_special_mapping vdso_vvar_mapping = {
> + .name = "[vvar]",
> + .fault = vvar_fault,
> +};
> +
> +struct vm_area_struct *vdso_install_vvar_mapping(struct mm_struct *mm, unsigned long addr)
> +{
> + return _install_special_mapping(mm, addr, VDSO_NR_PAGES * PAGE_SIZE,
> + VM_READ | VM_MAYREAD | VM_IO | VM_DONTDUMP | VM_PFNMAP,
> + &vdso_vvar_mapping);
> +}
> +
> +#ifdef CONFIG_TIME_NS
> +/*
> + * The vvar page layout depends on whether a task belongs to the root or
> + * non-root time namespace. Whenever a task changes its namespace, the VVAR
> + * page tables are cleared and then they will be re-faulted with a
> + * corresponding layout.
> + * See also the comment near timens_setup_vdso_data() for details.
> + */
> +int vdso_join_timens(struct task_struct *task, struct time_namespace *ns)
> +{
> + struct mm_struct *mm = task->mm;
> + struct vm_area_struct *vma;
> + VMA_ITERATOR(vmi, mm, 0);
> +
> + mmap_read_lock(mm);
> + for_each_vma(vmi, vma) {
> + if (vma_is_special_mapping(vma, &vdso_vvar_mapping))
> + zap_vma_pages(vma);
> + }
> + mmap_read_unlock(mm);
> +
> + return 0;
> +}
> +#endif
> +
> +struct vdso_time_data *arch_get_vdso_data(void *vvar_page)
> +{
> + return (struct vdso_time_data *)vvar_page;
> +}
>
^ permalink raw reply [flat|nested] 29+ messages in thread* Re: [PATCH 03/17] vdso: Add generic time data storage
2024-12-18 7:32 ` Christophe Leroy
@ 2024-12-18 10:25 ` Thomas Weißschuh
0 siblings, 0 replies; 29+ messages in thread
From: Thomas Weißschuh @ 2024-12-18 10:25 UTC (permalink / raw)
To: Christophe Leroy
Cc: James E.J. Bottomley, Helge Deller, Andy Lutomirski,
Thomas Gleixner, Vincenzo Frascino, Anna-Maria Behnsen,
Frederic Weisbecker, Andrew Morton, Catalin Marinas, Will Deacon,
Theodore Ts'o, Jason A. Donenfeld, Paul Walmsley,
Palmer Dabbelt, Albert Ou, Huacai Chen, WANG Xuerui, Russell King,
Heiko Carstens, Vasily Gorbik, Alexander Gordeev,
Christian Borntraeger, Sven Schnelle, Thomas Bogendoerfer,
Michael Ellerman, Nicholas Piggin, Naveen N Rao,
Madhavan Srinivasan, Ingo Molnar, Borislav Petkov, Dave Hansen,
x86, H. Peter Anvin, Arnd Bergmann, linux-parisc, linux-kernel,
linux-arm-kernel, linux-riscv, loongarch, linux-s390, linux-mips,
linuxppc-dev, linux-arch, Nam Cao
Hi Christophe,
On Wed, Dec 18, 2024 at 08:32:14AM +0100, Christophe Leroy wrote:
> Le 16/12/2024 à 15:09, Thomas Weißschuh a écrit :
> > Historically each architecture defined their own way to store the vDSO
> > data page. Add a generic mechanism to provide storage for that page.
> >
> > Furthermore this generic storage will be extended to also provide
> > uniform storage for *non*-time-related data, like the random state or
> > architecture-specific data. These will have their own pages and data
> > structures, so rename 'vdso_data' into 'vdso_time_data' to make that
> > split clear from the name.
> >
> > Also introduce a new consistent naming scheme for the symbols related to
> > the vDSO, which makes it clear if the symbol is accessible from
> > userspace or kernel space and the type of data behind the symbol.
> >
> > The generic fault handler contains an optimization to prefault the vvar
> > page when the timens page is accessed. This was lifted from s390 and x86.
> >
> > Co-developed-by: Nam Cao <namcao@linutronix.de>
> > Signed-off-by: Nam Cao <namcao@linutronix.de>
> > Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
> > ---
> > MAINTAINERS | 1 +
> > include/linux/time_namespace.h | 1 +
> > include/linux/vdso_datastore.h | 10 +++++
> > include/vdso/datapage.h | 69 +++++++++++++++++++++++++----
> > lib/Kconfig | 1 +
> > lib/Makefile | 2 +
> > lib/vdso_kernel/Kconfig | 7 +++
> > lib/vdso_kernel/Makefile | 3 ++
> > lib/vdso_kernel/datastore.c | 99 ++++++++++++++++++++++++++++++++++++++++++
>
> There is only one single file, namely datastore.c. You don't need a new
> directory for that, I should go in lib/vdso/
lib/vdso/ currently only contains userspace code.
I don't have a strong opinion on that.
The lib/vdso_kernel location was suggested by tglx, maybe he has some
feedback. (Originally I put it into kernel/vdso_storage.c)
[..]
> > +enum vdso_pages {
> > + VDSO_TIME_PAGE_OFFSET,
> > + VDSO_TIMENS_PAGE_OFFSET,
> > + VDSO_NR_PAGES
> > +};
>
> Naming that VDSO_ is confusing. Most macros called VDSO_ are related to the
> VDSO Code. VDSO data related macros should be prefixed with VVAR_
Also a request from tglx.
[..]
Thanks!
Thomas
^ permalink raw reply [flat|nested] 29+ messages in thread
* [PATCH 04/17] vdso: Add generic random data storage
2024-12-16 14:09 [PATCH 00/17] vDSO: Introduce generic data storage Thomas Weißschuh
` (2 preceding siblings ...)
2024-12-16 14:09 ` [PATCH 03/17] vdso: Add generic time data storage Thomas Weißschuh
@ 2024-12-16 14:10 ` Thomas Weißschuh
2024-12-16 14:10 ` [PATCH 05/17] vdso: Add generic architecture-specific " Thomas Weißschuh
` (12 subsequent siblings)
16 siblings, 0 replies; 29+ messages in thread
From: Thomas Weißschuh @ 2024-12-16 14:10 UTC (permalink / raw)
To: James E.J. Bottomley, Helge Deller, Andy Lutomirski,
Thomas Gleixner, Vincenzo Frascino, Anna-Maria Behnsen,
Frederic Weisbecker, Andrew Morton, Catalin Marinas, Will Deacon,
Theodore Ts'o, Jason A. Donenfeld, Paul Walmsley,
Palmer Dabbelt, Albert Ou, Huacai Chen, WANG Xuerui, Russell King,
Heiko Carstens, Vasily Gorbik, Alexander Gordeev,
Christian Borntraeger, Sven Schnelle, Thomas Bogendoerfer,
Michael Ellerman, Nicholas Piggin, Christophe Leroy, Naveen N Rao,
Madhavan Srinivasan, Ingo Molnar, Borislav Petkov, Dave Hansen,
x86, H. Peter Anvin, Arnd Bergmann
Cc: linux-parisc, linux-kernel, linux-arm-kernel, linux-riscv,
loongarch, linux-s390, linux-mips, linuxppc-dev, linux-arch,
Nam Cao, Thomas Weißschuh
Extend the generic vDSO data storage with a page for the random state data.
The random state data is stored in a dedicated page, as the existing
storage page is only meant for time-related, time-namespace-aware data.
This simplifies to access logic to not need to handle time namespaces
anymore and also frees up more space in the time-related page.
In case further generic vDSO data store is required it can be added to
the random state page.
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
---
include/vdso/datapage.h | 24 ++++++++++++++++++++++++
lib/vdso_kernel/datastore.c | 14 ++++++++++++++
2 files changed, 38 insertions(+)
diff --git a/include/vdso/datapage.h b/include/vdso/datapage.h
index 69af424413db1f265607d0f1bdbf88550548c5ba..5ce322422fcb7ba77aeafddbf132fd3e5dbc5a0c 100644
--- a/include/vdso/datapage.h
+++ b/include/vdso/datapage.h
@@ -145,8 +145,10 @@ extern struct vdso_rng_data _vdso_rng_data __attribute__((visibility("hidden")))
#else
extern const struct vdso_time_data vdso_u_time_data[CS_BASES] __attribute__((visibility("hidden")));
extern const struct vdso_time_data vdso_u_timens_data[CS_BASES] __attribute__((visibility("hidden")));
+extern const struct vdso_rng_data vdso_u_rng_data __attribute__((visibility("hidden")));
extern struct vdso_time_data *vdso_k_time_data;
+extern struct vdso_rng_data *vdso_k_rng_data;
#endif
/**
@@ -162,6 +164,7 @@ union vdso_data_store {
enum vdso_pages {
VDSO_TIME_PAGE_OFFSET,
VDSO_TIMENS_PAGE_OFFSET,
+ VDSO_RNG_PAGE_OFFSET,
VDSO_NR_PAGES
};
@@ -185,6 +188,20 @@ static __always_inline const struct vdso_time_data *__arch_get_vdso_u_timens_dat
#define __arch_get_timens_vdso_data(vd) __arch_get_vdso_u_timens_data()
#endif /* CONFIG_TIME_NS */
+#ifdef CONFIG_VDSO_GETRANDOM
+static __always_inline const struct vdso_rng_data *__arch_get_vdso_u_rng_data(void)
+{
+ return &vdso_u_rng_data;
+}
+#define __arch_get_vdso_rng_data __arch_get_vdso_u_rng_data
+
+static __always_inline struct vdso_rng_data *__arch_get_vdso_k_rng_data(void)
+{
+ return vdso_k_rng_data;
+}
+#define __arch_get_k_vdso_rng_data __arch_get_vdso_k_rng_data
+#endif /* CONFIG_VDSO_GETRANDOM */
+
#endif /* CONFIG_GENERIC_VDSO_DATA_STORE */
/*
@@ -211,10 +228,17 @@ static __always_inline const struct vdso_time_data *__arch_get_vdso_u_timens_dat
#define __vdso_u_timens_data
#endif
+#ifdef CONFIG_VDSO_GETRANDOM
+#define __vdso_u_rng_data PROVIDE(vdso_u_rng_data = vdso_u_data + 2 * PAGE_SIZE);
+#else
+#define __vdso_u_rng_data
+#endif
+
#define VDSO_VVAR_SYMS \
PROVIDE(vdso_u_data = . - __VDSO_PAGES * PAGE_SIZE); \
PROVIDE(vdso_u_time_data = vdso_u_data); \
__vdso_u_timens_data \
+ __vdso_u_rng_data \
#endif /* !__ASSEMBLY__ */
diff --git a/lib/vdso_kernel/datastore.c b/lib/vdso_kernel/datastore.c
index c9cd269b1ed1b6cdd5fdf9fe929d0b778314b962..0d4f5317b508a54b4f3295f0335d1eefce74d78c 100644
--- a/lib/vdso_kernel/datastore.c
+++ b/lib/vdso_kernel/datastore.c
@@ -15,6 +15,15 @@ static union vdso_data_store vdso_time_data_store __page_aligned_data;
struct vdso_time_data *vdso_k_time_data = vdso_time_data_store.data;
static_assert(sizeof(vdso_time_data_store) == PAGE_SIZE);
+#ifdef CONFIG_VDSO_GETRANDOM
+static union {
+ struct vdso_rng_data data;
+ u8 page[PAGE_SIZE];
+} vdso_rng_data_store __page_aligned_data;
+struct vdso_rng_data *vdso_k_rng_data = &vdso_rng_data_store.data;
+static_assert(sizeof(vdso_rng_data_store) == PAGE_SIZE);
+#endif /* CONFIG_VDSO_GETRANDOM */
+
static vm_fault_t vvar_fault(const struct vm_special_mapping *sm,
struct vm_area_struct *vma, struct vm_fault *vmf)
{
@@ -49,6 +58,11 @@ static vm_fault_t vvar_fault(const struct vm_special_mapping *sm,
return VM_FAULT_SIGBUS;
pfn = __phys_to_pfn(__pa_symbol(vdso_k_time_data));
break;
+ case VDSO_RNG_PAGE_OFFSET:
+ if (!IS_ENABLED(CONFIG_VDSO_GETRANDOM))
+ return VM_FAULT_SIGBUS;
+ pfn = __phys_to_pfn(__pa_symbol(vdso_k_rng_data));
+ break;
default:
return VM_FAULT_SIGBUS;
}
--
2.47.1
^ permalink raw reply related [flat|nested] 29+ messages in thread* [PATCH 05/17] vdso: Add generic architecture-specific data storage
2024-12-16 14:09 [PATCH 00/17] vDSO: Introduce generic data storage Thomas Weißschuh
` (3 preceding siblings ...)
2024-12-16 14:10 ` [PATCH 04/17] vdso: Add generic random " Thomas Weißschuh
@ 2024-12-16 14:10 ` Thomas Weißschuh
2024-12-16 14:10 ` [PATCH 06/17] arm64: vdso: Switch to generic storage implementation Thomas Weißschuh
` (11 subsequent siblings)
16 siblings, 0 replies; 29+ messages in thread
From: Thomas Weißschuh @ 2024-12-16 14:10 UTC (permalink / raw)
To: James E.J. Bottomley, Helge Deller, Andy Lutomirski,
Thomas Gleixner, Vincenzo Frascino, Anna-Maria Behnsen,
Frederic Weisbecker, Andrew Morton, Catalin Marinas, Will Deacon,
Theodore Ts'o, Jason A. Donenfeld, Paul Walmsley,
Palmer Dabbelt, Albert Ou, Huacai Chen, WANG Xuerui, Russell King,
Heiko Carstens, Vasily Gorbik, Alexander Gordeev,
Christian Borntraeger, Sven Schnelle, Thomas Bogendoerfer,
Michael Ellerman, Nicholas Piggin, Christophe Leroy, Naveen N Rao,
Madhavan Srinivasan, Ingo Molnar, Borislav Petkov, Dave Hansen,
x86, H. Peter Anvin, Arnd Bergmann
Cc: linux-parisc, linux-kernel, linux-arm-kernel, linux-riscv,
loongarch, linux-s390, linux-mips, linuxppc-dev, linux-arch,
Nam Cao, Thomas Weißschuh
Some architectures need to architecture-specific data to the vDSO.
Enable the generic vDSO storage mechanism to both store and map this
data. Some architectures require more than a single page, like
LoongArch, so prepare for that usecase, too.
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
---
arch/Kconfig | 4 ++++
include/vdso/datapage.h | 32 ++++++++++++++++++++++++++++++++
lib/vdso_kernel/datastore.c | 14 ++++++++++++++
3 files changed, 50 insertions(+)
diff --git a/arch/Kconfig b/arch/Kconfig
index 6682b2a53e342cbacc05b70ef99cb1c47efe55e8..48f37e6c00674f433a0d6e6e05ce72c27cf000b7 100644
--- a/arch/Kconfig
+++ b/arch/Kconfig
@@ -1576,6 +1576,10 @@ config HAVE_SPARSE_SYSCALL_NR
entries at 4000, 5000 and 6000 locations. This option turns on syscall
related optimizations for a given architecture.
+config ARCH_HAS_VDSO_ARCH_DATA
+ depends on GENERIC_VDSO_DATA_STORE
+ bool
+
config ARCH_HAS_VDSO_TIME_DATA
bool
diff --git a/include/vdso/datapage.h b/include/vdso/datapage.h
index 5ce322422fcb7ba77aeafddbf132fd3e5dbc5a0c..b3227f1cf62895aa60ce0ca96afa42259f4771f9 100644
--- a/include/vdso/datapage.h
+++ b/include/vdso/datapage.h
@@ -9,11 +9,13 @@
#include <uapi/linux/types.h>
#include <uapi/asm-generic/errno-base.h>
+#include <vdso/align.h>
#include <vdso/bits.h>
#include <vdso/clocksource.h>
#include <vdso/ktime.h>
#include <vdso/limits.h>
#include <vdso/math64.h>
+#include <vdso/page.h>
#include <vdso/processor.h>
#include <vdso/time.h>
#include <vdso/time32.h>
@@ -25,6 +27,15 @@
struct arch_vdso_time_data {};
#endif
+#if defined(CONFIG_ARCH_HAS_VDSO_ARCH_DATA)
+#include <asm/vdso/arch_data.h>
+#elif defined(CONFIG_GENERIC_VDSO_DATA_STORE)
+struct vdso_arch_data {
+ /* Needed for the generic code, never actually used at runtime */
+ char __unused;
+};
+#endif
+
#define VDSO_BASES (CLOCK_TAI + 1)
#define VDSO_HRES (BIT(CLOCK_REALTIME) | \
BIT(CLOCK_MONOTONIC) | \
@@ -146,9 +157,11 @@ extern struct vdso_rng_data _vdso_rng_data __attribute__((visibility("hidden")))
extern const struct vdso_time_data vdso_u_time_data[CS_BASES] __attribute__((visibility("hidden")));
extern const struct vdso_time_data vdso_u_timens_data[CS_BASES] __attribute__((visibility("hidden")));
extern const struct vdso_rng_data vdso_u_rng_data __attribute__((visibility("hidden")));
+extern const struct vdso_arch_data vdso_u_arch_data __attribute__((visibility("hidden")));
extern struct vdso_time_data *vdso_k_time_data;
extern struct vdso_rng_data *vdso_k_rng_data;
+extern struct vdso_arch_data *vdso_k_arch_data;
#endif
/**
@@ -161,10 +174,15 @@ union vdso_data_store {
#ifdef CONFIG_GENERIC_VDSO_DATA_STORE
+#define VDSO_ARCH_DATA_SIZE ALIGN(sizeof(struct vdso_arch_data), PAGE_SIZE)
+#define VDSO_ARCH_DATA_PAGES (VDSO_ARCH_DATA_SIZE >> PAGE_SHIFT)
+
enum vdso_pages {
VDSO_TIME_PAGE_OFFSET,
VDSO_TIMENS_PAGE_OFFSET,
VDSO_RNG_PAGE_OFFSET,
+ VDSO_ARCH_PAGES_START,
+ VDSO_ARCH_PAGES_END = VDSO_ARCH_PAGES_START + VDSO_ARCH_DATA_PAGES - 1,
VDSO_NR_PAGES
};
@@ -204,6 +222,13 @@ static __always_inline struct vdso_rng_data *__arch_get_vdso_k_rng_data(void)
#endif /* CONFIG_GENERIC_VDSO_DATA_STORE */
+#ifdef CONFIG_ARCH_HAS_VDSO_ARCH_DATA
+static __always_inline const struct vdso_arch_data *__arch_get_vdso_u_arch_data(void)
+{
+ return &vdso_u_arch_data;
+}
+#endif /* CONFIG_ARCH_HAS_VDSO_ARCH_DATA */
+
/*
* The generic vDSO implementation requires that gettimeofday.h
* provides:
@@ -234,11 +259,18 @@ static __always_inline struct vdso_rng_data *__arch_get_vdso_k_rng_data(void)
#define __vdso_u_rng_data
#endif
+#ifdef CONFIG_ARCH_HAS_VDSO_ARCH_DATA
+#define __vdso_u_arch_data PROVIDE(vdso_u_arch_data = vdso_u_data + 3 * PAGE_SIZE);
+#else
+#define __vdso_u_arch_data
+#endif
+
#define VDSO_VVAR_SYMS \
PROVIDE(vdso_u_data = . - __VDSO_PAGES * PAGE_SIZE); \
PROVIDE(vdso_u_time_data = vdso_u_data); \
__vdso_u_timens_data \
__vdso_u_rng_data \
+ __vdso_u_arch_data \
#endif /* !__ASSEMBLY__ */
diff --git a/lib/vdso_kernel/datastore.c b/lib/vdso_kernel/datastore.c
index 0d4f5317b508a54b4f3295f0335d1eefce74d78c..668cac8c4f80ac71d3f6de71e98e963bc65a1c15 100644
--- a/lib/vdso_kernel/datastore.c
+++ b/lib/vdso_kernel/datastore.c
@@ -24,6 +24,14 @@ struct vdso_rng_data *vdso_k_rng_data = &vdso_rng_data_store.data;
static_assert(sizeof(vdso_rng_data_store) == PAGE_SIZE);
#endif /* CONFIG_VDSO_GETRANDOM */
+#ifdef CONFIG_ARCH_HAS_VDSO_ARCH_DATA
+static union {
+ struct vdso_arch_data data;
+ u8 page[VDSO_ARCH_DATA_SIZE];
+} vdso_arch_data_store __page_aligned_data;
+struct vdso_arch_data *vdso_k_arch_data = &vdso_arch_data_store.data;
+#endif
+
static vm_fault_t vvar_fault(const struct vm_special_mapping *sm,
struct vm_area_struct *vma, struct vm_fault *vmf)
{
@@ -63,6 +71,12 @@ static vm_fault_t vvar_fault(const struct vm_special_mapping *sm,
return VM_FAULT_SIGBUS;
pfn = __phys_to_pfn(__pa_symbol(vdso_k_rng_data));
break;
+ case VDSO_ARCH_PAGES_START ... VDSO_ARCH_PAGES_END:
+ if (!IS_ENABLED(CONFIG_ARCH_HAS_VDSO_ARCH_DATA))
+ return VM_FAULT_SIGBUS;
+ pfn = __phys_to_pfn(__pa_symbol(vdso_k_arch_data)) +
+ vmf->pgoff - VDSO_ARCH_PAGES_START;
+ break;
default:
return VM_FAULT_SIGBUS;
}
--
2.47.1
^ permalink raw reply related [flat|nested] 29+ messages in thread* [PATCH 06/17] arm64: vdso: Switch to generic storage implementation
2024-12-16 14:09 [PATCH 00/17] vDSO: Introduce generic data storage Thomas Weißschuh
` (4 preceding siblings ...)
2024-12-16 14:10 ` [PATCH 05/17] vdso: Add generic architecture-specific " Thomas Weißschuh
@ 2024-12-16 14:10 ` Thomas Weißschuh
2024-12-16 14:10 ` [PATCH 07/17] riscv: " Thomas Weißschuh
` (10 subsequent siblings)
16 siblings, 0 replies; 29+ messages in thread
From: Thomas Weißschuh @ 2024-12-16 14:10 UTC (permalink / raw)
To: James E.J. Bottomley, Helge Deller, Andy Lutomirski,
Thomas Gleixner, Vincenzo Frascino, Anna-Maria Behnsen,
Frederic Weisbecker, Andrew Morton, Catalin Marinas, Will Deacon,
Theodore Ts'o, Jason A. Donenfeld, Paul Walmsley,
Palmer Dabbelt, Albert Ou, Huacai Chen, WANG Xuerui, Russell King,
Heiko Carstens, Vasily Gorbik, Alexander Gordeev,
Christian Borntraeger, Sven Schnelle, Thomas Bogendoerfer,
Michael Ellerman, Nicholas Piggin, Christophe Leroy, Naveen N Rao,
Madhavan Srinivasan, Ingo Molnar, Borislav Petkov, Dave Hansen,
x86, H. Peter Anvin, Arnd Bergmann
Cc: linux-parisc, linux-kernel, linux-arm-kernel, linux-riscv,
loongarch, linux-s390, linux-mips, linuxppc-dev, linux-arch,
Nam Cao, Thomas Weißschuh
The generic storage implementation provides the same features as the
custom one. However it can be shared between architectures, making
maintenance easier.
This switch also moves the random state data out of the time data page.
The currently used hardcoded __VDSO_RND_DATA_OFFSET does not take into
account changes to the time data page layout.
Co-developed-by: Nam Cao <namcao@linutronix.de>
Signed-off-by: Nam Cao <namcao@linutronix.de>
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
---
arch/arm64/Kconfig | 1 +
arch/arm64/include/asm/vdso.h | 2 +-
arch/arm64/include/asm/vdso/compat_gettimeofday.h | 32 ++++----
arch/arm64/include/asm/vdso/getrandom.h | 12 ---
arch/arm64/include/asm/vdso/gettimeofday.h | 16 +---
arch/arm64/include/asm/vdso/vsyscall.h | 25 +------
arch/arm64/kernel/vdso.c | 90 ++---------------------
arch/arm64/kernel/vdso/vdso.lds.S | 7 +-
arch/arm64/kernel/vdso32/vdso.lds.S | 7 +-
9 files changed, 31 insertions(+), 161 deletions(-)
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index 100570a048c5e8892c0112704f9ca74c4fc55b27..1a4a78ec593328d6e6bceacc1abb0821eab988ca 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -159,6 +159,7 @@ config ARM64
select GENERIC_SMP_IDLE_THREAD
select GENERIC_TIME_VSYSCALL
select GENERIC_GETTIMEOFDAY
+ select GENERIC_VDSO_DATA_STORE
select GENERIC_VDSO_TIME_NS
select HARDIRQS_SW_RESEND
select HAS_IOPORT
diff --git a/arch/arm64/include/asm/vdso.h b/arch/arm64/include/asm/vdso.h
index 3e3c3fdb184274abd20647335b19e81e709506db..61679070f595cd25fb2f516b5b077599a9570689 100644
--- a/arch/arm64/include/asm/vdso.h
+++ b/arch/arm64/include/asm/vdso.h
@@ -5,7 +5,7 @@
#ifndef __ASM_VDSO_H
#define __ASM_VDSO_H
-#define __VVAR_PAGES 2
+#define __VDSO_PAGES 4
#ifndef __ASSEMBLY__
diff --git a/arch/arm64/include/asm/vdso/compat_gettimeofday.h b/arch/arm64/include/asm/vdso/compat_gettimeofday.h
index 778c1202bbbf9f5db6bfced62a833d50e1675b08..a386bba3efa794e6f3f0018c85531dd7e708ff86 100644
--- a/arch/arm64/include/asm/vdso/compat_gettimeofday.h
+++ b/arch/arm64/include/asm/vdso/compat_gettimeofday.h
@@ -104,7 +104,7 @@ int clock_getres32_fallback(clockid_t _clkid, struct old_timespec32 *_ts)
}
static __always_inline u64 __arch_get_hw_counter(s32 clock_mode,
- const struct vdso_data *vd)
+ const struct vdso_time_data *vd)
{
u64 res;
@@ -131,43 +131,45 @@ static __always_inline u64 __arch_get_hw_counter(s32 clock_mode,
return res;
}
-static __always_inline const struct vdso_data *__arch_get_vdso_data(void)
+static __always_inline const struct vdso_time_data *__aarch64_get_vdso_u_time_data(void)
{
- const struct vdso_data *ret;
+ const struct vdso_time_data *ret;
/*
- * This simply puts &_vdso_data into ret. The reason why we don't use
- * `ret = _vdso_data` is that the compiler tends to optimise this in a
- * very suboptimal way: instead of keeping &_vdso_data in a register,
- * it goes through a relocation almost every time _vdso_data must be
+ * This simply puts &_vdso_time_data into ret. The reason why we don't use
+ * `ret = _vdso_time_data` is that the compiler tends to optimise this in a
+ * very suboptimal way: instead of keeping &_vdso_time_data in a register,
+ * it goes through a relocation almost every time _vdso_time_data must be
* accessed (even in subfunctions). This is both time and space
* consuming: each relocation uses a word in the code section, and it
* has to be loaded at runtime.
*
* This trick hides the assignment from the compiler. Since it cannot
* track where the pointer comes from, it will only use one relocation
- * where __arch_get_vdso_data() is called, and then keep the result in
- * a register.
+ * where __aarch64_get_vdso_u_time_data() is called, and then keep the
+ * result in a register.
*/
- asm volatile("mov %0, %1" : "=r"(ret) : "r"(_vdso_data));
+ asm volatile("mov %0, %1" : "=r"(ret) : "r"(vdso_u_time_data));
return ret;
}
+#define __arch_get_vdso_u_time_data __aarch64_get_vdso_u_time_data
#ifdef CONFIG_TIME_NS
static __always_inline
-const struct vdso_data *__arch_get_timens_vdso_data(const struct vdso_data *vd)
+const struct vdso_time_data *__aarch64_get_vdso_u_timens_data(void)
{
- const struct vdso_data *ret;
+ const struct vdso_time_data *ret;
- /* See __arch_get_vdso_data(). */
- asm volatile("mov %0, %1" : "=r"(ret) : "r"(_timens_data));
+ /* See __aarch64_get_vdso_u_time_data(). */
+ asm volatile("mov %0, %1" : "=r"(ret) : "r"(vdso_u_timens_data));
return ret;
}
+#define __arch_get_vdso_u_timens_data __aarch64_get_vdso_u_timens_data
#endif
-static inline bool vdso_clocksource_ok(const struct vdso_data *vd)
+static inline bool vdso_clocksource_ok(const struct vdso_time_data *vd)
{
return vd->clock_mode == VDSO_CLOCKMODE_ARCHTIMER;
}
diff --git a/arch/arm64/include/asm/vdso/getrandom.h b/arch/arm64/include/asm/vdso/getrandom.h
index 342f807e204442c95cb9e9a849da38effbe50334..a2197da1951b021baff4eb08b3f1c314df2f5f23 100644
--- a/arch/arm64/include/asm/vdso/getrandom.h
+++ b/arch/arm64/include/asm/vdso/getrandom.h
@@ -33,18 +33,6 @@ static __always_inline ssize_t getrandom_syscall(void *_buffer, size_t _len, uns
return ret;
}
-static __always_inline const struct vdso_rng_data *__arch_get_vdso_rng_data(void)
-{
- /*
- * The RNG data is in the real VVAR data page, but if a task belongs to a time namespace
- * then VVAR_DATA_PAGE_OFFSET points to the namespace-specific VVAR page and VVAR_TIMENS_
- * PAGE_OFFSET points to the real VVAR page.
- */
- if (IS_ENABLED(CONFIG_TIME_NS) && _vdso_data->clock_mode == VDSO_CLOCKMODE_TIMENS)
- return (void *)&_vdso_rng_data + VVAR_TIMENS_PAGE_OFFSET * (1UL << CONFIG_PAGE_SHIFT);
- return &_vdso_rng_data;
-}
-
#endif /* !__ASSEMBLY__ */
#endif /* __ASM_VDSO_GETRANDOM_H */
diff --git a/arch/arm64/include/asm/vdso/gettimeofday.h b/arch/arm64/include/asm/vdso/gettimeofday.h
index 764d13e2916c559bc8fd7efa032b6f468ac0d4a2..92a2b59a9f3df4d20feb483e6d8ebd1d813b7932 100644
--- a/arch/arm64/include/asm/vdso/gettimeofday.h
+++ b/arch/arm64/include/asm/vdso/gettimeofday.h
@@ -67,7 +67,7 @@ int clock_getres_fallback(clockid_t _clkid, struct __kernel_timespec *_ts)
}
static __always_inline u64 __arch_get_hw_counter(s32 clock_mode,
- const struct vdso_data *vd)
+ const struct vdso_time_data *vd)
{
u64 res;
@@ -99,20 +99,6 @@ static __always_inline u64 __arch_get_hw_counter(s32 clock_mode,
return res;
}
-static __always_inline
-const struct vdso_data *__arch_get_vdso_data(void)
-{
- return _vdso_data;
-}
-
-#ifdef CONFIG_TIME_NS
-static __always_inline
-const struct vdso_data *__arch_get_timens_vdso_data(const struct vdso_data *vd)
-{
- return _timens_data;
-}
-#endif
-
#endif /* !__ASSEMBLY__ */
#endif /* __ASM_VDSO_GETTIMEOFDAY_H */
diff --git a/arch/arm64/include/asm/vdso/vsyscall.h b/arch/arm64/include/asm/vdso/vsyscall.h
index eea51946d45a2f8c7eebfff971d74878be53a798..3f65cbd00635aab50a4e0c6058d38b39fd6d43a9 100644
--- a/arch/arm64/include/asm/vdso/vsyscall.h
+++ b/arch/arm64/include/asm/vdso/vsyscall.h
@@ -2,41 +2,18 @@
#ifndef __ASM_VDSO_VSYSCALL_H
#define __ASM_VDSO_VSYSCALL_H
-#define __VDSO_RND_DATA_OFFSET 480
-
#ifndef __ASSEMBLY__
#include <vdso/datapage.h>
-enum vvar_pages {
- VVAR_DATA_PAGE_OFFSET,
- VVAR_TIMENS_PAGE_OFFSET,
- VVAR_NR_PAGES,
-};
-
#define VDSO_PRECISION_MASK ~(0xFF00ULL<<48)
-extern struct vdso_data *vdso_data;
/*
* Update the vDSO data page to keep in sync with kernel timekeeping.
*/
static __always_inline
-struct vdso_data *__arm64_get_k_vdso_data(void)
-{
- return vdso_data;
-}
-#define __arch_get_k_vdso_data __arm64_get_k_vdso_data
-
-static __always_inline
-struct vdso_rng_data *__arm64_get_k_vdso_rnd_data(void)
-{
- return (void *)vdso_data + __VDSO_RND_DATA_OFFSET;
-}
-#define __arch_get_k_vdso_rng_data __arm64_get_k_vdso_rnd_data
-
-static __always_inline
-void __arm64_update_vsyscall(struct vdso_data *vdata)
+void __arm64_update_vsyscall(struct vdso_time_data *vdata)
{
vdata[CS_HRES_COARSE].mask = VDSO_PRECISION_MASK;
vdata[CS_RAW].mask = VDSO_PRECISION_MASK;
diff --git a/arch/arm64/kernel/vdso.c b/arch/arm64/kernel/vdso.c
index e8ed8e5b713b525abac828b1a17ab9e6d974a3e9..887ac0b05961eb83afe649a0afcaf7deda4b186b 100644
--- a/arch/arm64/kernel/vdso.c
+++ b/arch/arm64/kernel/vdso.c
@@ -18,7 +18,7 @@
#include <linux/sched.h>
#include <linux/signal.h>
#include <linux/slab.h>
-#include <linux/time_namespace.h>
+#include <linux/vdso_datastore.h>
#include <linux/vmalloc.h>
#include <vdso/datapage.h>
#include <vdso/helpers.h>
@@ -57,12 +57,6 @@ static struct vdso_abi_info vdso_info[] __ro_after_init = {
#endif /* CONFIG_COMPAT_VDSO */
};
-/*
- * The vDSO data page.
- */
-static union vdso_data_store vdso_data_store __page_aligned_data;
-struct vdso_data *vdso_data = vdso_data_store.data;
-
static int vdso_mremap(const struct vm_special_mapping *sm,
struct vm_area_struct *new_vma)
{
@@ -104,78 +98,6 @@ static int __init __vdso_init(enum vdso_abi abi)
return 0;
}
-#ifdef CONFIG_TIME_NS
-struct vdso_data *arch_get_vdso_data(void *vvar_page)
-{
- return (struct vdso_data *)(vvar_page);
-}
-
-static const struct vm_special_mapping vvar_map;
-
-/*
- * The vvar mapping contains data for a specific time namespace, so when a task
- * changes namespace we must unmap its vvar data for the old namespace.
- * Subsequent faults will map in data for the new namespace.
- *
- * For more details see timens_setup_vdso_data().
- */
-int vdso_join_timens(struct task_struct *task, struct time_namespace *ns)
-{
- struct mm_struct *mm = task->mm;
- struct vm_area_struct *vma;
- VMA_ITERATOR(vmi, mm, 0);
-
- mmap_read_lock(mm);
-
- for_each_vma(vmi, vma) {
- if (vma_is_special_mapping(vma, &vvar_map))
- zap_vma_pages(vma);
- }
-
- mmap_read_unlock(mm);
- return 0;
-}
-#endif
-
-static vm_fault_t vvar_fault(const struct vm_special_mapping *sm,
- struct vm_area_struct *vma, struct vm_fault *vmf)
-{
- struct page *timens_page = find_timens_vvar_page(vma);
- unsigned long pfn;
-
- switch (vmf->pgoff) {
- case VVAR_DATA_PAGE_OFFSET:
- if (timens_page)
- pfn = page_to_pfn(timens_page);
- else
- pfn = sym_to_pfn(vdso_data);
- break;
-#ifdef CONFIG_TIME_NS
- case VVAR_TIMENS_PAGE_OFFSET:
- /*
- * If a task belongs to a time namespace then a namespace
- * specific VVAR is mapped with the VVAR_DATA_PAGE_OFFSET and
- * the real VVAR page is mapped with the VVAR_TIMENS_PAGE_OFFSET
- * offset.
- * See also the comment near timens_setup_vdso_data().
- */
- if (!timens_page)
- return VM_FAULT_SIGBUS;
- pfn = sym_to_pfn(vdso_data);
- break;
-#endif /* CONFIG_TIME_NS */
- default:
- return VM_FAULT_SIGBUS;
- }
-
- return vmf_insert_pfn(vma, vmf->address, pfn);
-}
-
-static const struct vm_special_mapping vvar_map = {
- .name = "[vvar]",
- .fault = vvar_fault,
-};
-
static int __setup_additional_pages(enum vdso_abi abi,
struct mm_struct *mm,
struct linux_binprm *bprm,
@@ -185,11 +107,11 @@ static int __setup_additional_pages(enum vdso_abi abi,
unsigned long gp_flags = 0;
void *ret;
- BUILD_BUG_ON(VVAR_NR_PAGES != __VVAR_PAGES);
+ BUILD_BUG_ON(VDSO_NR_PAGES != __VDSO_PAGES);
vdso_text_len = vdso_info[abi].vdso_pages << PAGE_SHIFT;
/* Be sure to map the data page */
- vdso_mapping_len = vdso_text_len + VVAR_NR_PAGES * PAGE_SIZE;
+ vdso_mapping_len = vdso_text_len + VDSO_NR_PAGES * PAGE_SIZE;
vdso_base = get_unmapped_area(NULL, 0, vdso_mapping_len, 0, 0);
if (IS_ERR_VALUE(vdso_base)) {
@@ -197,16 +119,14 @@ static int __setup_additional_pages(enum vdso_abi abi,
goto up_fail;
}
- ret = _install_special_mapping(mm, vdso_base, VVAR_NR_PAGES * PAGE_SIZE,
- VM_READ|VM_MAYREAD|VM_PFNMAP,
- &vvar_map);
+ ret = vdso_install_vvar_mapping(mm, vdso_base);
if (IS_ERR(ret))
goto up_fail;
if (system_supports_bti_kernel())
gp_flags = VM_ARM64_BTI;
- vdso_base += VVAR_NR_PAGES * PAGE_SIZE;
+ vdso_base += VDSO_NR_PAGES * PAGE_SIZE;
mm->context.vdso = (void *)vdso_base;
ret = _install_special_mapping(mm, vdso_base, vdso_text_len,
VM_READ|VM_EXEC|gp_flags|
diff --git a/arch/arm64/kernel/vdso/vdso.lds.S b/arch/arm64/kernel/vdso/vdso.lds.S
index 4ec32e86a8da22d5e2315e55ae2e86ec8e7f5f9a..2e20d0593f182bfefcf39aebb1400f32af0866dc 100644
--- a/arch/arm64/kernel/vdso/vdso.lds.S
+++ b/arch/arm64/kernel/vdso/vdso.lds.S
@@ -20,11 +20,8 @@ OUTPUT_ARCH(aarch64)
SECTIONS
{
- PROVIDE(_vdso_data = . - __VVAR_PAGES * PAGE_SIZE);
- PROVIDE(_vdso_rng_data = _vdso_data + __VDSO_RND_DATA_OFFSET);
-#ifdef CONFIG_TIME_NS
- PROVIDE(_timens_data = _vdso_data + PAGE_SIZE);
-#endif
+ VDSO_VVAR_SYMS
+
. = SIZEOF_HEADERS;
.hash : { *(.hash) } :text
diff --git a/arch/arm64/kernel/vdso32/vdso.lds.S b/arch/arm64/kernel/vdso32/vdso.lds.S
index 732702a187e9e8b62972ee0aad75c23568e5e779..e02b27487ce80497663dd042357558fea201fcce 100644
--- a/arch/arm64/kernel/vdso32/vdso.lds.S
+++ b/arch/arm64/kernel/vdso32/vdso.lds.S
@@ -12,16 +12,15 @@
#include <asm/page.h>
#include <asm/vdso.h>
#include <asm-generic/vmlinux.lds.h>
+#include <vdso/datapage.h>
OUTPUT_FORMAT("elf32-littlearm", "elf32-bigarm", "elf32-littlearm")
OUTPUT_ARCH(arm)
SECTIONS
{
- PROVIDE_HIDDEN(_vdso_data = . - __VVAR_PAGES * PAGE_SIZE);
-#ifdef CONFIG_TIME_NS
- PROVIDE_HIDDEN(_timens_data = _vdso_data + PAGE_SIZE);
-#endif
+ VDSO_VVAR_SYMS
+
. = SIZEOF_HEADERS;
.hash : { *(.hash) } :text
--
2.47.1
^ permalink raw reply related [flat|nested] 29+ messages in thread* [PATCH 07/17] riscv: vdso: Switch to generic storage implementation
2024-12-16 14:09 [PATCH 00/17] vDSO: Introduce generic data storage Thomas Weißschuh
` (5 preceding siblings ...)
2024-12-16 14:10 ` [PATCH 06/17] arm64: vdso: Switch to generic storage implementation Thomas Weißschuh
@ 2024-12-16 14:10 ` Thomas Weißschuh
2024-12-18 15:08 ` Conor Dooley
2024-12-16 14:10 ` [PATCH 08/17] LoongArch: vDSO: " Thomas Weißschuh
` (9 subsequent siblings)
16 siblings, 1 reply; 29+ messages in thread
From: Thomas Weißschuh @ 2024-12-16 14:10 UTC (permalink / raw)
To: James E.J. Bottomley, Helge Deller, Andy Lutomirski,
Thomas Gleixner, Vincenzo Frascino, Anna-Maria Behnsen,
Frederic Weisbecker, Andrew Morton, Catalin Marinas, Will Deacon,
Theodore Ts'o, Jason A. Donenfeld, Paul Walmsley,
Palmer Dabbelt, Albert Ou, Huacai Chen, WANG Xuerui, Russell King,
Heiko Carstens, Vasily Gorbik, Alexander Gordeev,
Christian Borntraeger, Sven Schnelle, Thomas Bogendoerfer,
Michael Ellerman, Nicholas Piggin, Christophe Leroy, Naveen N Rao,
Madhavan Srinivasan, Ingo Molnar, Borislav Petkov, Dave Hansen,
x86, H. Peter Anvin, Arnd Bergmann
Cc: linux-parisc, linux-kernel, linux-arm-kernel, linux-riscv,
loongarch, linux-s390, linux-mips, linuxppc-dev, linux-arch,
Nam Cao, Thomas Weißschuh
The generic storage implementation provides the same features as the
custom one. However it can be shared between architectures, making
maintenance easier.
Co-developed-by: Nam Cao <namcao@linutronix.de>
Signed-off-by: Nam Cao <namcao@linutronix.de>
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
---
arch/riscv/Kconfig | 3 +-
arch/riscv/include/asm/vdso.h | 2 +-
.../include/asm/vdso/{time_data.h => arch_data.h} | 8 +-
arch/riscv/include/asm/vdso/gettimeofday.h | 14 +---
arch/riscv/include/asm/vdso/vsyscall.h | 9 ---
arch/riscv/kernel/sys_hwprobe.c | 3 +-
arch/riscv/kernel/vdso.c | 90 +---------------------
arch/riscv/kernel/vdso/hwprobe.c | 6 +-
arch/riscv/kernel/vdso/vdso.lds.S | 7 +-
9 files changed, 18 insertions(+), 124 deletions(-)
diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
index d4a7ca0388c071b536df59c0eb11d55f9080c7cd..a42d74aa53fe7c18e76820499d0ae43cd3b0c0bd 100644
--- a/arch/riscv/Kconfig
+++ b/arch/riscv/Kconfig
@@ -52,7 +52,7 @@ config RISCV
select ARCH_HAS_SYSCALL_WRAPPER
select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
select ARCH_HAS_UBSAN
- select ARCH_HAS_VDSO_TIME_DATA
+ select ARCH_HAS_VDSO_ARCH_DATA if HAVE_GENERIC_VDSO
select ARCH_KEEP_MEMBLOCK if ACPI
select ARCH_MHP_MEMMAP_ON_MEMORY_ENABLE if 64BIT && MMU
select ARCH_OPTIONAL_KERNEL_RWX if ARCH_HAS_STRICT_KERNEL_RWX
@@ -115,6 +115,7 @@ config RISCV
select GENERIC_SCHED_CLOCK
select GENERIC_SMP_IDLE_THREAD
select GENERIC_TIME_VSYSCALL if MMU && 64BIT
+ select GENERIC_VDSO_DATA_STORE if HAVE_GENERIC_VDSO
select GENERIC_VDSO_TIME_NS if HAVE_GENERIC_VDSO
select HARDIRQS_SW_RESEND
select HAS_IOPORT if MMU
diff --git a/arch/riscv/include/asm/vdso.h b/arch/riscv/include/asm/vdso.h
index f891478829a52c41e06240f67611694cc28197d9..c130d8100232cbe50e52e35eb418e354bd114cb7 100644
--- a/arch/riscv/include/asm/vdso.h
+++ b/arch/riscv/include/asm/vdso.h
@@ -14,7 +14,7 @@
*/
#ifdef CONFIG_MMU
-#define __VVAR_PAGES 2
+#define __VDSO_PAGES 4
#ifndef __ASSEMBLY__
#include <generated/vdso-offsets.h>
diff --git a/arch/riscv/include/asm/vdso/time_data.h b/arch/riscv/include/asm/vdso/arch_data.h
similarity index 71%
rename from arch/riscv/include/asm/vdso/time_data.h
rename to arch/riscv/include/asm/vdso/arch_data.h
index dfa65228999bed41dfd6c5e36cb678e1e055eec8..da57a3786f7a53c866fc00948826b4a2d839940f 100644
--- a/arch/riscv/include/asm/vdso/time_data.h
+++ b/arch/riscv/include/asm/vdso/arch_data.h
@@ -1,12 +1,12 @@
/* SPDX-License-Identifier: GPL-2.0 */
-#ifndef __RISCV_ASM_VDSO_TIME_DATA_H
-#define __RISCV_ASM_VDSO_TIME_DATA_H
+#ifndef __RISCV_ASM_VDSO_ARCH_DATA_H
+#define __RISCV_ASM_VDSO_ARCH_DATA_H
#include <linux/types.h>
#include <vdso/datapage.h>
#include <asm/hwprobe.h>
-struct arch_vdso_time_data {
+struct vdso_arch_data {
/* Stash static answers to the hwprobe queries when all CPUs are selected. */
__u64 all_cpu_hwprobe_values[RISCV_HWPROBE_MAX_KEY + 1];
@@ -14,4 +14,4 @@ struct arch_vdso_time_data {
__u8 homogeneous_cpus;
};
-#endif /* __RISCV_ASM_VDSO_TIME_DATA_H */
+#endif /* __RISCV_ASM_VDSO_ARCH_DATA_H */
diff --git a/arch/riscv/include/asm/vdso/gettimeofday.h b/arch/riscv/include/asm/vdso/gettimeofday.h
index ba3283cf7accaa93a38512d2c17eda0eefde0612..29164f84f93cec6e28251e6a0adfbc341ac88241 100644
--- a/arch/riscv/include/asm/vdso/gettimeofday.h
+++ b/arch/riscv/include/asm/vdso/gettimeofday.h
@@ -69,7 +69,7 @@ int clock_getres_fallback(clockid_t _clkid, struct __kernel_timespec *_ts)
#endif /* CONFIG_GENERIC_TIME_VSYSCALL */
static __always_inline u64 __arch_get_hw_counter(s32 clock_mode,
- const struct vdso_data *vd)
+ const struct vdso_time_data *vd)
{
/*
* The purpose of csr_read(CSR_TIME) is to trap the system into
@@ -79,18 +79,6 @@ static __always_inline u64 __arch_get_hw_counter(s32 clock_mode,
return csr_read(CSR_TIME);
}
-static __always_inline const struct vdso_data *__arch_get_vdso_data(void)
-{
- return _vdso_data;
-}
-
-#ifdef CONFIG_TIME_NS
-static __always_inline
-const struct vdso_data *__arch_get_timens_vdso_data(const struct vdso_data *vd)
-{
- return _timens_data;
-}
-#endif
#endif /* !__ASSEMBLY__ */
#endif /* __ASM_VDSO_GETTIMEOFDAY_H */
diff --git a/arch/riscv/include/asm/vdso/vsyscall.h b/arch/riscv/include/asm/vdso/vsyscall.h
index e8a9c4b53c0c9f4744196eed800b21f3918d1040..1140b54b4bc8278d7a322036cd9f84f71258f246 100644
--- a/arch/riscv/include/asm/vdso/vsyscall.h
+++ b/arch/riscv/include/asm/vdso/vsyscall.h
@@ -6,15 +6,6 @@
#include <vdso/datapage.h>
-extern struct vdso_data *vdso_data;
-
-static __always_inline struct vdso_data *__riscv_get_k_vdso_data(void)
-{
- return vdso_data;
-}
-
-#define __arch_get_k_vdso_data __riscv_get_k_vdso_data
-
/* The asm-generic header needs to be included after the definitions above */
#include <asm-generic/vdso/vsyscall.h>
diff --git a/arch/riscv/kernel/sys_hwprobe.c b/arch/riscv/kernel/sys_hwprobe.c
index cb93adfffc486e710409fd3b8a8ab22525ac4093..37e155dd3ab26da7b6a03e0b11b467e5aac51091 100644
--- a/arch/riscv/kernel/sys_hwprobe.c
+++ b/arch/riscv/kernel/sys_hwprobe.c
@@ -445,8 +445,7 @@ static int do_riscv_hwprobe(struct riscv_hwprobe __user *pairs,
static int __init init_hwprobe_vdso_data(void)
{
- struct vdso_data *vd = __arch_get_k_vdso_data();
- struct arch_vdso_time_data *avd = &vd->arch_data;
+ struct vdso_arch_data *avd = vdso_k_arch_data;
u64 id_bitsmash = 0;
struct riscv_hwprobe pair;
int key;
diff --git a/arch/riscv/kernel/vdso.c b/arch/riscv/kernel/vdso.c
index 3ca3ae4277e187e790a8bf513a9e80d8b6290bb2..cc2895d1fbc2fe752b3edc94f4e28a6a8fca7a3b 100644
--- a/arch/riscv/kernel/vdso.c
+++ b/arch/riscv/kernel/vdso.c
@@ -13,20 +13,11 @@
#include <linux/err.h>
#include <asm/page.h>
#include <asm/vdso.h>
-#include <linux/time_namespace.h>
+#include <linux/vdso_datastore.h>
#include <vdso/datapage.h>
#include <vdso/vsyscall.h>
-enum vvar_pages {
- VVAR_DATA_PAGE_OFFSET,
- VVAR_TIMENS_PAGE_OFFSET,
- VVAR_NR_PAGES,
-};
-
-#define VVAR_SIZE (VVAR_NR_PAGES << PAGE_SHIFT)
-
-static union vdso_data_store vdso_data_store __page_aligned_data;
-struct vdso_data *vdso_data = vdso_data_store.data;
+#define VVAR_SIZE (VDSO_NR_PAGES << PAGE_SHIFT)
struct __vdso_info {
const char *name;
@@ -79,78 +70,6 @@ static void __init __vdso_init(struct __vdso_info *vdso_info)
vdso_info->cm->pages = vdso_pagelist;
}
-#ifdef CONFIG_TIME_NS
-struct vdso_data *arch_get_vdso_data(void *vvar_page)
-{
- return (struct vdso_data *)(vvar_page);
-}
-
-static const struct vm_special_mapping rv_vvar_map;
-
-/*
- * The vvar mapping contains data for a specific time namespace, so when a task
- * changes namespace we must unmap its vvar data for the old namespace.
- * Subsequent faults will map in data for the new namespace.
- *
- * For more details see timens_setup_vdso_data().
- */
-int vdso_join_timens(struct task_struct *task, struct time_namespace *ns)
-{
- struct mm_struct *mm = task->mm;
- struct vm_area_struct *vma;
- VMA_ITERATOR(vmi, mm, 0);
-
- mmap_read_lock(mm);
-
- for_each_vma(vmi, vma) {
- if (vma_is_special_mapping(vma, &rv_vvar_map))
- zap_vma_pages(vma);
- }
-
- mmap_read_unlock(mm);
- return 0;
-}
-#endif
-
-static vm_fault_t vvar_fault(const struct vm_special_mapping *sm,
- struct vm_area_struct *vma, struct vm_fault *vmf)
-{
- struct page *timens_page = find_timens_vvar_page(vma);
- unsigned long pfn;
-
- switch (vmf->pgoff) {
- case VVAR_DATA_PAGE_OFFSET:
- if (timens_page)
- pfn = page_to_pfn(timens_page);
- else
- pfn = sym_to_pfn(vdso_data);
- break;
-#ifdef CONFIG_TIME_NS
- case VVAR_TIMENS_PAGE_OFFSET:
- /*
- * If a task belongs to a time namespace then a namespace
- * specific VVAR is mapped with the VVAR_DATA_PAGE_OFFSET and
- * the real VVAR page is mapped with the VVAR_TIMENS_PAGE_OFFSET
- * offset.
- * See also the comment near timens_setup_vdso_data().
- */
- if (!timens_page)
- return VM_FAULT_SIGBUS;
- pfn = sym_to_pfn(vdso_data);
- break;
-#endif /* CONFIG_TIME_NS */
- default:
- return VM_FAULT_SIGBUS;
- }
-
- return vmf_insert_pfn(vma, vmf->address, pfn);
-}
-
-static const struct vm_special_mapping rv_vvar_map = {
- .name = "[vvar]",
- .fault = vvar_fault,
-};
-
static struct vm_special_mapping rv_vdso_map __ro_after_init = {
.name = "[vdso]",
.mremap = vdso_mremap,
@@ -196,7 +115,7 @@ static int __setup_additional_pages(struct mm_struct *mm,
unsigned long vdso_base, vdso_text_len, vdso_mapping_len;
void *ret;
- BUILD_BUG_ON(VVAR_NR_PAGES != __VVAR_PAGES);
+ BUILD_BUG_ON(VDSO_NR_PAGES != __VDSO_PAGES);
vdso_text_len = vdso_info->vdso_pages << PAGE_SHIFT;
/* Be sure to map the data page */
@@ -208,8 +127,7 @@ static int __setup_additional_pages(struct mm_struct *mm,
goto up_fail;
}
- ret = _install_special_mapping(mm, vdso_base, VVAR_SIZE,
- (VM_READ | VM_MAYREAD | VM_PFNMAP), &rv_vvar_map);
+ ret = vdso_install_vvar_mapping(mm, vdso_base);
if (IS_ERR(ret))
goto up_fail;
diff --git a/arch/riscv/kernel/vdso/hwprobe.c b/arch/riscv/kernel/vdso/hwprobe.c
index a158c029344f60c022e7565757ff44df7e3d89e5..b699b1f65f254ad5b787e168d48a9b0e76d1f37b 100644
--- a/arch/riscv/kernel/vdso/hwprobe.c
+++ b/arch/riscv/kernel/vdso/hwprobe.c
@@ -16,8 +16,7 @@ static int riscv_vdso_get_values(struct riscv_hwprobe *pairs, size_t pair_count,
size_t cpusetsize, unsigned long *cpus,
unsigned int flags)
{
- const struct vdso_data *vd = __arch_get_vdso_data();
- const struct arch_vdso_time_data *avd = &vd->arch_data;
+ const struct vdso_arch_data *avd = __arch_get_vdso_u_arch_data();
bool all_cpus = !cpusetsize && !cpus;
struct riscv_hwprobe *p = pairs;
struct riscv_hwprobe *end = pairs + pair_count;
@@ -51,8 +50,7 @@ static int riscv_vdso_get_cpus(struct riscv_hwprobe *pairs, size_t pair_count,
size_t cpusetsize, unsigned long *cpus,
unsigned int flags)
{
- const struct vdso_data *vd = __arch_get_vdso_data();
- const struct arch_vdso_time_data *avd = &vd->arch_data;
+ const struct vdso_arch_data *avd = __arch_get_vdso_u_arch_data();
struct riscv_hwprobe *p = pairs;
struct riscv_hwprobe *end = pairs + pair_count;
unsigned char *c = (unsigned char *)cpus;
diff --git a/arch/riscv/kernel/vdso/vdso.lds.S b/arch/riscv/kernel/vdso/vdso.lds.S
index cbe2a179331d2511a8b4a26c06383e46131661b1..8e86965a8aae4d7c5a36d0f26026cd1c8680b339 100644
--- a/arch/riscv/kernel/vdso/vdso.lds.S
+++ b/arch/riscv/kernel/vdso/vdso.lds.S
@@ -4,15 +4,14 @@
*/
#include <asm/page.h>
#include <asm/vdso.h>
+#include <vdso/datapage.h>
OUTPUT_ARCH(riscv)
SECTIONS
{
- PROVIDE(_vdso_data = . - __VVAR_PAGES * PAGE_SIZE);
-#ifdef CONFIG_TIME_NS
- PROVIDE(_timens_data = _vdso_data + PAGE_SIZE);
-#endif
+ VDSO_VVAR_SYMS
+
. = SIZEOF_HEADERS;
.hash : { *(.hash) } :text
--
2.47.1
^ permalink raw reply related [flat|nested] 29+ messages in thread* Re: [PATCH 07/17] riscv: vdso: Switch to generic storage implementation
2024-12-16 14:10 ` [PATCH 07/17] riscv: " Thomas Weißschuh
@ 2024-12-18 15:08 ` Conor Dooley
2024-12-18 15:46 ` Thomas Weißschuh
0 siblings, 1 reply; 29+ messages in thread
From: Conor Dooley @ 2024-12-18 15:08 UTC (permalink / raw)
To: Thomas Weißschuh
Cc: James E.J. Bottomley, Helge Deller, Andy Lutomirski,
Thomas Gleixner, Vincenzo Frascino, Anna-Maria Behnsen,
Frederic Weisbecker, Andrew Morton, Catalin Marinas, Will Deacon,
Theodore Ts'o, Jason A. Donenfeld, Paul Walmsley,
Palmer Dabbelt, Albert Ou, Huacai Chen, WANG Xuerui, Russell King,
Heiko Carstens, Vasily Gorbik, Alexander Gordeev,
Christian Borntraeger, Sven Schnelle, Thomas Bogendoerfer,
Michael Ellerman, Nicholas Piggin, Christophe Leroy, Naveen N Rao,
Madhavan Srinivasan, Ingo Molnar, Borislav Petkov, Dave Hansen,
x86, H. Peter Anvin, Arnd Bergmann, linux-parisc, linux-kernel,
linux-arm-kernel, linux-riscv, loongarch, linux-s390, linux-mips,
linuxppc-dev, linux-arch, Nam Cao
[-- Attachment #1: Type: text/plain, Size: 4926 bytes --]
On Mon, Dec 16, 2024 at 03:10:03PM +0100, Thomas Weißschuh wrote:
> The generic storage implementation provides the same features as the
> custom one. However it can be shared between architectures, making
> maintenance easier.
>
> Co-developed-by: Nam Cao <namcao@linutronix.de>
> Signed-off-by: Nam Cao <namcao@linutronix.de>
> Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
> ---
> arch/riscv/Kconfig | 3 +-
> arch/riscv/include/asm/vdso.h | 2 +-
> .../include/asm/vdso/{time_data.h => arch_data.h} | 8 +-
> arch/riscv/include/asm/vdso/gettimeofday.h | 14 +---
> arch/riscv/include/asm/vdso/vsyscall.h | 9 ---
> arch/riscv/kernel/sys_hwprobe.c | 3 +-
> arch/riscv/kernel/vdso.c | 90 +---------------------
> arch/riscv/kernel/vdso/hwprobe.c | 6 +-
> arch/riscv/kernel/vdso/vdso.lds.S | 7 +-
> 9 files changed, 18 insertions(+), 124 deletions(-)
Fails to build:
Patch 7/17: Test 1/12: .github/scripts/patches/tests/build_rv32_defconfig.sh
/build/tmp.cAQOaMfDA3/arch/riscv/kernel/vdso/hwprobe.c:11:33: warning: declaration of 'struct riscv_hwprobe' will not be visible outside of this function [-Wvisibility]
/build/tmp.cAQOaMfDA3/arch/riscv/kernel/vdso/hwprobe.c:15:41: warning: declaration of 'struct riscv_hwprobe' will not be visible outside of this function [-Wvisibility]
/build/tmp.cAQOaMfDA3/arch/riscv/kernel/vdso/hwprobe.c:19:37: error: call to undeclared function '__arch_get_vdso_u_arch_data'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]
/build/tmp.cAQOaMfDA3/arch/riscv/kernel/vdso/hwprobe.c:19:31: error: incompatible integer to pointer conversion initializing 'const struct vdso_arch_data *' with an expression of type 'int' [-Wint-conversion]
/build/tmp.cAQOaMfDA3/arch/riscv/kernel/vdso/hwprobe.c:22:36: error: arithmetic on a pointer to an incomplete type 'struct riscv_hwprobe'
/build/tmp.cAQOaMfDA3/arch/riscv/kernel/vdso/hwprobe.c:30:40: error: incomplete definition of type 'const struct vdso_arch_data'
/build/tmp.cAQOaMfDA3/arch/riscv/kernel/vdso/hwprobe.c:31:24: error: incompatible pointer types passing 'struct riscv_hwprobe *' to parameter of type 'struct riscv_hwprobe *' [-Werror,-Wincompatible-pointer-types]
/build/tmp.cAQOaMfDA3/arch/riscv/kernel/vdso/hwprobe.c:35:7: error: call to undeclared function 'riscv_hwprobe_key_is_valid'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]
/build/tmp.cAQOaMfDA3/arch/riscv/kernel/vdso/hwprobe.c:35:35: error: incomplete definition of type 'struct riscv_hwprobe'
/build/tmp.cAQOaMfDA3/arch/riscv/kernel/vdso/hwprobe.c:36:5: error: incomplete definition of type 'struct riscv_hwprobe'
/build/tmp.cAQOaMfDA3/arch/riscv/kernel/vdso/hwprobe.c:36:18: error: incomplete definition of type 'const struct vdso_arch_data'
/build/tmp.cAQOaMfDA3/arch/riscv/kernel/vdso/hwprobe.c:36:44: error: incomplete definition of type 'struct riscv_hwprobe'
/build/tmp.cAQOaMfDA3/arch/riscv/kernel/vdso/hwprobe.c:39:5: error: incomplete definition of type 'struct riscv_hwprobe'
/build/tmp.cAQOaMfDA3/arch/riscv/kernel/vdso/hwprobe.c:40:5: error: incomplete definition of type 'struct riscv_hwprobe'
/build/tmp.cAQOaMfDA3/arch/riscv/kernel/vdso/hwprobe.c:43:4: error: arithmetic on a pointer to an incomplete type 'struct riscv_hwprobe'
/build/tmp.cAQOaMfDA3/arch/riscv/kernel/vdso/hwprobe.c:49:39: warning: declaration of 'struct riscv_hwprobe' will not be visible outside of this function [-Wvisibility]
/build/tmp.cAQOaMfDA3/arch/riscv/kernel/vdso/hwprobe.c:53:37: error: call to undeclared function '__arch_get_vdso_u_arch_data'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]
/build/tmp.cAQOaMfDA3/arch/riscv/kernel/vdso/hwprobe.c:53:31: error: incompatible integer to pointer conversion initializing 'const struct vdso_arch_data *' with an expression of type 'int' [-Wint-conversion]
/build/tmp.cAQOaMfDA3/arch/riscv/kernel/vdso/hwprobe.c:55:36: error: arithmetic on a pointer to an incomplete type 'struct riscv_hwprobe'
/build/tmp.cAQOaMfDA3/arch/riscv/kernel/vdso/hwprobe.c:71:61: error: incomplete definition of type 'const struct vdso_arch_data'
/build/tmp.cAQOaMfDA3/arch/riscv/kernel/vdso/hwprobe.c:71:29: error: use of undeclared identifier 'RISCV_HWPROBE_WHICH_CPUS'
/build/tmp.cAQOaMfDA3/arch/riscv/kernel/vdso/hwprobe.c:72:24: error: incompatible pointer types passing 'struct riscv_hwprobe *' to parameter of type 'struct riscv_hwprobe *' [-Werror,-Wincompatible-pointer-types]
fatal error: too many errors emitted, stopping now [-ferror-limit=]
Might be a clang thing, allmodconfig with clang doesn't build either.
[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 228 bytes --]
^ permalink raw reply [flat|nested] 29+ messages in thread* Re: [PATCH 07/17] riscv: vdso: Switch to generic storage implementation
2024-12-18 15:08 ` Conor Dooley
@ 2024-12-18 15:46 ` Thomas Weißschuh
2024-12-18 16:35 ` Arnd Bergmann
0 siblings, 1 reply; 29+ messages in thread
From: Thomas Weißschuh @ 2024-12-18 15:46 UTC (permalink / raw)
To: Conor Dooley
Cc: James E.J. Bottomley, Helge Deller, Andy Lutomirski,
Thomas Gleixner, Vincenzo Frascino, Anna-Maria Behnsen,
Frederic Weisbecker, Andrew Morton, Catalin Marinas, Will Deacon,
Theodore Ts'o, Jason A. Donenfeld, Paul Walmsley,
Palmer Dabbelt, Albert Ou, Huacai Chen, WANG Xuerui, Russell King,
Heiko Carstens, Vasily Gorbik, Alexander Gordeev,
Christian Borntraeger, Sven Schnelle, Thomas Bogendoerfer,
Michael Ellerman, Nicholas Piggin, Christophe Leroy, Naveen N Rao,
Madhavan Srinivasan, Ingo Molnar, Borislav Petkov, Dave Hansen,
x86, H. Peter Anvin, Arnd Bergmann, linux-parisc, linux-kernel,
linux-arm-kernel, linux-riscv, loongarch, linux-s390, linux-mips,
linuxppc-dev, linux-arch, Nam Cao
Hi Conor,
On Wed, Dec 18, 2024 at 03:08:28PM +0000, Conor Dooley wrote:
> On Mon, Dec 16, 2024 at 03:10:03PM +0100, Thomas Weißschuh wrote:
> > The generic storage implementation provides the same features as the
> > custom one. However it can be shared between architectures, making
> > maintenance easier.
> >
> > Co-developed-by: Nam Cao <namcao@linutronix.de>
> > Signed-off-by: Nam Cao <namcao@linutronix.de>
> > Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
> > ---
> > arch/riscv/Kconfig | 3 +-
> > arch/riscv/include/asm/vdso.h | 2 +-
> > .../include/asm/vdso/{time_data.h => arch_data.h} | 8 +-
> > arch/riscv/include/asm/vdso/gettimeofday.h | 14 +---
> > arch/riscv/include/asm/vdso/vsyscall.h | 9 ---
> > arch/riscv/kernel/sys_hwprobe.c | 3 +-
> > arch/riscv/kernel/vdso.c | 90 +---------------------
> > arch/riscv/kernel/vdso/hwprobe.c | 6 +-
> > arch/riscv/kernel/vdso/vdso.lds.S | 7 +-
> > 9 files changed, 18 insertions(+), 124 deletions(-)
>
> Fails to build:
> Patch 7/17: Test 1/12: .github/scripts/patches/tests/build_rv32_defconfig.sh
> /build/tmp.cAQOaMfDA3/arch/riscv/kernel/vdso/hwprobe.c:11:33: warning: declaration of 'struct riscv_hwprobe' will not be visible outside of this function [-Wvisibility]
> /build/tmp.cAQOaMfDA3/arch/riscv/kernel/vdso/hwprobe.c:15:41: warning: declaration of 'struct riscv_hwprobe' will not be visible outside of this function [-Wvisibility]
> /build/tmp.cAQOaMfDA3/arch/riscv/kernel/vdso/hwprobe.c:19:37: error: call to undeclared function '__arch_get_vdso_u_arch_data'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]
> /build/tmp.cAQOaMfDA3/arch/riscv/kernel/vdso/hwprobe.c:19:31: error: incompatible integer to pointer conversion initializing 'const struct vdso_arch_data *' with an expression of type 'int' [-Wint-conversion]
> /build/tmp.cAQOaMfDA3/arch/riscv/kernel/vdso/hwprobe.c:22:36: error: arithmetic on a pointer to an incomplete type 'struct riscv_hwprobe'
> /build/tmp.cAQOaMfDA3/arch/riscv/kernel/vdso/hwprobe.c:30:40: error: incomplete definition of type 'const struct vdso_arch_data'
> /build/tmp.cAQOaMfDA3/arch/riscv/kernel/vdso/hwprobe.c:31:24: error: incompatible pointer types passing 'struct riscv_hwprobe *' to parameter of type 'struct riscv_hwprobe *' [-Werror,-Wincompatible-pointer-types]
> /build/tmp.cAQOaMfDA3/arch/riscv/kernel/vdso/hwprobe.c:35:7: error: call to undeclared function 'riscv_hwprobe_key_is_valid'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]
> /build/tmp.cAQOaMfDA3/arch/riscv/kernel/vdso/hwprobe.c:35:35: error: incomplete definition of type 'struct riscv_hwprobe'
> /build/tmp.cAQOaMfDA3/arch/riscv/kernel/vdso/hwprobe.c:36:5: error: incomplete definition of type 'struct riscv_hwprobe'
> /build/tmp.cAQOaMfDA3/arch/riscv/kernel/vdso/hwprobe.c:36:18: error: incomplete definition of type 'const struct vdso_arch_data'
> /build/tmp.cAQOaMfDA3/arch/riscv/kernel/vdso/hwprobe.c:36:44: error: incomplete definition of type 'struct riscv_hwprobe'
> /build/tmp.cAQOaMfDA3/arch/riscv/kernel/vdso/hwprobe.c:39:5: error: incomplete definition of type 'struct riscv_hwprobe'
> /build/tmp.cAQOaMfDA3/arch/riscv/kernel/vdso/hwprobe.c:40:5: error: incomplete definition of type 'struct riscv_hwprobe'
> /build/tmp.cAQOaMfDA3/arch/riscv/kernel/vdso/hwprobe.c:43:4: error: arithmetic on a pointer to an incomplete type 'struct riscv_hwprobe'
> /build/tmp.cAQOaMfDA3/arch/riscv/kernel/vdso/hwprobe.c:49:39: warning: declaration of 'struct riscv_hwprobe' will not be visible outside of this function [-Wvisibility]
> /build/tmp.cAQOaMfDA3/arch/riscv/kernel/vdso/hwprobe.c:53:37: error: call to undeclared function '__arch_get_vdso_u_arch_data'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]
> /build/tmp.cAQOaMfDA3/arch/riscv/kernel/vdso/hwprobe.c:53:31: error: incompatible integer to pointer conversion initializing 'const struct vdso_arch_data *' with an expression of type 'int' [-Wint-conversion]
> /build/tmp.cAQOaMfDA3/arch/riscv/kernel/vdso/hwprobe.c:55:36: error: arithmetic on a pointer to an incomplete type 'struct riscv_hwprobe'
> /build/tmp.cAQOaMfDA3/arch/riscv/kernel/vdso/hwprobe.c:71:61: error: incomplete definition of type 'const struct vdso_arch_data'
> /build/tmp.cAQOaMfDA3/arch/riscv/kernel/vdso/hwprobe.c:71:29: error: use of undeclared identifier 'RISCV_HWPROBE_WHICH_CPUS'
> /build/tmp.cAQOaMfDA3/arch/riscv/kernel/vdso/hwprobe.c:72:24: error: incompatible pointer types passing 'struct riscv_hwprobe *' to parameter of type 'struct riscv_hwprobe *' [-Werror,-Wincompatible-pointer-types]
> fatal error: too many errors emitted, stopping now [-ferror-limit=]
>
> Might be a clang thing, allmodconfig with clang doesn't build either.
The proposed generic storage infrastructure currently expects that all
its users also use HAVE_GENERIC_VDSO.
I missed rv32 when checking this assumption.
I can add a bunch of ifdefs into the storage code to handle this.
Or we re-add the time vDSO functions which were removed in commit
d4c08b9776b3 ("riscv: Use latest system call ABI").
Today there are upstream ports of musl and glibc which can use them.
(currently musl even tries to use __vdso_clock_gettime() as 64-bit only
on rv32 due to a copy-and-paste error from its rv64 code)
There is precedence in providing 64bit only vDSO functions, for example
__vdso_clock_gettime64() in arm.
I do have a small, so far untested, proof-of-concept patch for it.
This would even be less code than the ifdefs.
What do you think about it?
Thomas
^ permalink raw reply [flat|nested] 29+ messages in thread* Re: [PATCH 07/17] riscv: vdso: Switch to generic storage implementation
2024-12-18 15:46 ` Thomas Weißschuh
@ 2024-12-18 16:35 ` Arnd Bergmann
2024-12-19 6:30 ` Thomas Weißschuh
0 siblings, 1 reply; 29+ messages in thread
From: Arnd Bergmann @ 2024-12-18 16:35 UTC (permalink / raw)
To: Thomas Weißschuh, Conor Dooley
Cc: James E . J . Bottomley, Helge Deller, Andy Lutomirski,
Thomas Gleixner, Vincenzo Frascino, Anna-Maria Gleixner,
Frederic Weisbecker, Andrew Morton, Catalin Marinas, Will Deacon,
Theodore Ts'o, Jason A . Donenfeld, Paul Walmsley,
Palmer Dabbelt, Albert Ou, Huacai Chen, WANG Xuerui, Russell King,
Heiko Carstens, Vasily Gorbik, Alexander Gordeev,
Christian Borntraeger, Sven Schnelle, Thomas Bogendoerfer,
Michael Ellerman, Nicholas Piggin, Christophe Leroy, Naveen N Rao,
Madhavan Srinivasan, Ingo Molnar, Borislav Petkov, Dave Hansen,
x86, H. Peter Anvin, linux-parisc, linux-kernel, linux-arm-kernel,
linux-riscv, loongarch, linux-s390, linux-mips, linuxppc-dev,
Linux-Arch, Nam Cao
On Wed, Dec 18, 2024, at 16:46, Thomas Weißschuh wrote:
> On Wed, Dec 18, 2024 at 03:08:28PM +0000, Conor Dooley wrote:
>> On Mon, Dec 16, 2024 at 03:10:03PM +0100, Thomas Weißschuh wrote:
>> Might be a clang thing, allmodconfig with clang doesn't build either.
>
> The proposed generic storage infrastructure currently expects that all
> its users also use HAVE_GENERIC_VDSO.
> I missed rv32 when checking this assumption.
>
> I can add a bunch of ifdefs into the storage code to handle this.
>
> Or we re-add the time vDSO functions which were removed in commit
> d4c08b9776b3 ("riscv: Use latest system call ABI").
> Today there are upstream ports of musl and glibc which can use them.
> (currently musl even tries to use __vdso_clock_gettime() as 64-bit only
> on rv32 due to a copy-and-paste error from its rv64 code)
Adding back __vdso_clock_gettime() wouldn't work on rv32 because there
is no fallback syscall for it, and it wouldn't really help since
there is no existing userspace that uses time32 structures.
> There is precedence in providing 64bit only vDSO functions, for example
> __vdso_clock_gettime64() in arm.
> I do have a small, so far untested, proof-of-concept patch for it.
> This would even be less code than the ifdefs.
>
> What do you think about it?
Yes, simply exposing the normal time64 syscalls through vdso
should be fine. I think this currently works on everything except
rv32 and sparc32, probably because neither of them have actual
users that are able to test.
Arnd
^ permalink raw reply [flat|nested] 29+ messages in thread* Re: [PATCH 07/17] riscv: vdso: Switch to generic storage implementation
2024-12-18 16:35 ` Arnd Bergmann
@ 2024-12-19 6:30 ` Thomas Weißschuh
2024-12-19 7:03 ` Arnd Bergmann
0 siblings, 1 reply; 29+ messages in thread
From: Thomas Weißschuh @ 2024-12-19 6:30 UTC (permalink / raw)
To: Arnd Bergmann
Cc: Conor Dooley, James E . J . Bottomley, Helge Deller,
Andy Lutomirski, Thomas Gleixner, Vincenzo Frascino,
Anna-Maria Gleixner, Frederic Weisbecker, Andrew Morton,
Catalin Marinas, Will Deacon, Theodore Ts'o,
Jason A . Donenfeld, Paul Walmsley, Palmer Dabbelt, Albert Ou,
Huacai Chen, WANG Xuerui, Russell King, Heiko Carstens,
Vasily Gorbik, Alexander Gordeev, Christian Borntraeger,
Sven Schnelle, Thomas Bogendoerfer, Michael Ellerman,
Nicholas Piggin, Christophe Leroy, Naveen N Rao,
Madhavan Srinivasan, Ingo Molnar, Borislav Petkov, Dave Hansen,
x86, H. Peter Anvin, linux-parisc, linux-kernel, linux-arm-kernel,
linux-riscv, loongarch, linux-s390, linux-mips, linuxppc-dev,
Linux-Arch, Nam Cao
On Wed, Dec 18, 2024 at 05:35:31PM +0100, Arnd Bergmann wrote:
> On Wed, Dec 18, 2024, at 16:46, Thomas Weißschuh wrote:
> > On Wed, Dec 18, 2024 at 03:08:28PM +0000, Conor Dooley wrote:
> >> On Mon, Dec 16, 2024 at 03:10:03PM +0100, Thomas Weißschuh wrote:
>
> >> Might be a clang thing, allmodconfig with clang doesn't build either.
> >
> > The proposed generic storage infrastructure currently expects that all
> > its users also use HAVE_GENERIC_VDSO.
> > I missed rv32 when checking this assumption.
> >
> > I can add a bunch of ifdefs into the storage code to handle this.
> >
> > Or we re-add the time vDSO functions which were removed in commit
> > d4c08b9776b3 ("riscv: Use latest system call ABI").
> > Today there are upstream ports of musl and glibc which can use them.
> > (currently musl even tries to use __vdso_clock_gettime() as 64-bit only
> > on rv32 due to a copy-and-paste error from its rv64 code)
>
> Adding back __vdso_clock_gettime() wouldn't work on rv32 because there
> is no fallback syscall for it, and it wouldn't really help since
> there is no existing userspace that uses time32 structures.
My original paragraph was worded confusingly.
It was about re-adding time-related vDSO function *in general*, not the
specific 32-bit ones.
The new ones should be 64-bit only, indeed.
> > There is precedence in providing 64bit only vDSO functions, for example
> > __vdso_clock_gettime64() in arm.
> > I do have a small, so far untested, proof-of-concept patch for it.
> > This would even be less code than the ifdefs.
> >
> > What do you think about it?
>
> Yes, simply exposing the normal time64 syscalls through vdso
> should be fine. I think this currently works on everything except
> rv32 and sparc32, probably because neither of them have actual
> users that are able to test.
Should it use the specific _vdso_clock_gettime64() naming or leave out
the 64 suffix?
General Note: I'll continue working on this next year.
Thanks,
Thomas
^ permalink raw reply [flat|nested] 29+ messages in thread* Re: [PATCH 07/17] riscv: vdso: Switch to generic storage implementation
2024-12-19 6:30 ` Thomas Weißschuh
@ 2024-12-19 7:03 ` Arnd Bergmann
0 siblings, 0 replies; 29+ messages in thread
From: Arnd Bergmann @ 2024-12-19 7:03 UTC (permalink / raw)
To: Thomas Weißschuh
Cc: Conor Dooley, James E . J . Bottomley, Helge Deller,
Andy Lutomirski, Thomas Gleixner, Vincenzo Frascino,
Anna-Maria Gleixner, Frederic Weisbecker, Andrew Morton,
Catalin Marinas, Will Deacon, Theodore Ts'o,
Jason A . Donenfeld, Paul Walmsley, Palmer Dabbelt, Albert Ou,
Huacai Chen, WANG Xuerui, Russell King, Heiko Carstens,
Vasily Gorbik, Alexander Gordeev, Christian Borntraeger,
Sven Schnelle, Thomas Bogendoerfer, Michael Ellerman,
Nicholas Piggin, Christophe Leroy, Naveen N Rao,
Madhavan Srinivasan, Ingo Molnar, Borislav Petkov, Dave Hansen,
x86, H. Peter Anvin, linux-parisc, linux-kernel, linux-arm-kernel,
linux-riscv, loongarch, linux-s390, linux-mips, linuxppc-dev,
Linux-Arch, Nam Cao
On Thu, Dec 19, 2024, at 07:30, Thomas Weißschuh wrote:
> On Wed, Dec 18, 2024 at 05:35:31PM +0100, Arnd Bergmann wrote:
>>
>> > There is precedence in providing 64bit only vDSO functions, for example
>> > __vdso_clock_gettime64() in arm.
>> > I do have a small, so far untested, proof-of-concept patch for it.
>> > This would even be less code than the ifdefs.
>> >
>> > What do you think about it?
>>
>> Yes, simply exposing the normal time64 syscalls through vdso
>> should be fine. I think this currently works on everything except
>> rv32 and sparc32, probably because neither of them have actual
>> users that are able to test.
>
> Should it use the specific _vdso_clock_gettime64() naming or leave out
> the 64 suffix?
The VDSO function name should match the syscall name, with the '64'
suffix. Any syscall ending in _time64 uses the __kernel_time64_t
derived types, while the corresponding syscall names that don't end
in _time64 take a __kernel_old_time_t, which is defined as
__kernel_long_t and only 32 bits wide.
Arnd
^ permalink raw reply [flat|nested] 29+ messages in thread
* [PATCH 08/17] LoongArch: vDSO: Switch to generic storage implementation
2024-12-16 14:09 [PATCH 00/17] vDSO: Introduce generic data storage Thomas Weißschuh
` (6 preceding siblings ...)
2024-12-16 14:10 ` [PATCH 07/17] riscv: " Thomas Weißschuh
@ 2024-12-16 14:10 ` Thomas Weißschuh
2024-12-16 14:10 ` [PATCH 09/17] arm: vdso: " Thomas Weißschuh
` (8 subsequent siblings)
16 siblings, 0 replies; 29+ messages in thread
From: Thomas Weißschuh @ 2024-12-16 14:10 UTC (permalink / raw)
To: James E.J. Bottomley, Helge Deller, Andy Lutomirski,
Thomas Gleixner, Vincenzo Frascino, Anna-Maria Behnsen,
Frederic Weisbecker, Andrew Morton, Catalin Marinas, Will Deacon,
Theodore Ts'o, Jason A. Donenfeld, Paul Walmsley,
Palmer Dabbelt, Albert Ou, Huacai Chen, WANG Xuerui, Russell King,
Heiko Carstens, Vasily Gorbik, Alexander Gordeev,
Christian Borntraeger, Sven Schnelle, Thomas Bogendoerfer,
Michael Ellerman, Nicholas Piggin, Christophe Leroy, Naveen N Rao,
Madhavan Srinivasan, Ingo Molnar, Borislav Petkov, Dave Hansen,
x86, H. Peter Anvin, Arnd Bergmann
Cc: linux-parisc, linux-kernel, linux-arm-kernel, linux-riscv,
loongarch, linux-s390, linux-mips, linuxppc-dev, linux-arch,
Nam Cao, Thomas Weißschuh
The generic storage implementation provides the same features as the
custom one. However it can be shared between architectures, making
maintenance easier.
Co-developed-by: Nam Cao <namcao@linutronix.de>
Signed-off-by: Nam Cao <namcao@linutronix.de>
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
---
arch/loongarch/Kconfig | 2 +
arch/loongarch/include/asm/vdso.h | 1 -
arch/loongarch/include/asm/vdso/arch_data.h | 25 +++++++
arch/loongarch/include/asm/vdso/getrandom.h | 5 --
arch/loongarch/include/asm/vdso/gettimeofday.h | 14 +---
arch/loongarch/include/asm/vdso/vdso.h | 38 +----------
arch/loongarch/include/asm/vdso/vsyscall.h | 17 -----
arch/loongarch/kernel/asm-offsets.c | 2 +-
arch/loongarch/kernel/vdso.c | 92 +-------------------------
arch/loongarch/vdso/vdso.lds.S | 8 +--
arch/loongarch/vdso/vgetcpu.c | 7 +-
11 files changed, 38 insertions(+), 173 deletions(-)
diff --git a/arch/loongarch/Kconfig b/arch/loongarch/Kconfig
index dae3a9104ca6584133d9b6a3059ee666c216d31b..6ec7ef705199fdd4039afd23ec9050a28aa894eb 100644
--- a/arch/loongarch/Kconfig
+++ b/arch/loongarch/Kconfig
@@ -29,6 +29,7 @@ config LOONGARCH
select ARCH_HAS_SET_MEMORY
select ARCH_HAS_SET_DIRECT_MAP
select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
+ select ARCH_HAS_VDSO_ARCH_DATA
select ARCH_INLINE_READ_LOCK if !PREEMPTION
select ARCH_INLINE_READ_LOCK_BH if !PREEMPTION
select ARCH_INLINE_READ_LOCK_IRQ if !PREEMPTION
@@ -104,6 +105,7 @@ config LOONGARCH
select GENERIC_SCHED_CLOCK
select GENERIC_SMP_IDLE_THREAD
select GENERIC_TIME_VSYSCALL
+ select GENERIC_VDSO_DATA_STORE
select GENERIC_VDSO_TIME_NS
select GPIOLIB
select HAS_IOPORT
diff --git a/arch/loongarch/include/asm/vdso.h b/arch/loongarch/include/asm/vdso.h
index d3ba35eb23e77082ea8ed564fe7378ad80df81b2..f72ec79e2dde52f8888750a53c4af85d6ab77b45 100644
--- a/arch/loongarch/include/asm/vdso.h
+++ b/arch/loongarch/include/asm/vdso.h
@@ -31,7 +31,6 @@ struct loongarch_vdso_info {
unsigned long size;
unsigned long offset_sigreturn;
struct vm_special_mapping code_mapping;
- struct vm_special_mapping data_mapping;
};
extern struct loongarch_vdso_info vdso_info;
diff --git a/arch/loongarch/include/asm/vdso/arch_data.h b/arch/loongarch/include/asm/vdso/arch_data.h
new file mode 100644
index 0000000000000000000000000000000000000000..322d0a5f1c844f02de9b074d6021e8e15116f8a2
--- /dev/null
+++ b/arch/loongarch/include/asm/vdso/arch_data.h
@@ -0,0 +1,25 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * Author: Huacai Chen <chenhuacai@loongson.cn>
+ * Copyright (C) 2020-2022 Loongson Technology Corporation Limited
+ */
+
+#ifndef _VDSO_ARCH_DATA_H
+#define _VDSO_ARCH_DATA_H
+
+#ifndef __ASSEMBLY__
+
+#include <asm/asm.h>
+#include <asm/vdso.h>
+
+struct vdso_pcpu_data {
+ u32 node;
+} ____cacheline_aligned_in_smp;
+
+struct vdso_arch_data {
+ struct vdso_pcpu_data pdata[NR_CPUS];
+};
+
+#endif /* __ASSEMBLY__ */
+
+#endif
diff --git a/arch/loongarch/include/asm/vdso/getrandom.h b/arch/loongarch/include/asm/vdso/getrandom.h
index e80f3c4ac7481ba7f9f5d9210fefa78c3293243b..48c43f55b039b42168698614d0479b7a872d20f3 100644
--- a/arch/loongarch/include/asm/vdso/getrandom.h
+++ b/arch/loongarch/include/asm/vdso/getrandom.h
@@ -28,11 +28,6 @@ static __always_inline ssize_t getrandom_syscall(void *_buffer, size_t _len, uns
return ret;
}
-static __always_inline const struct vdso_rng_data *__arch_get_vdso_rng_data(void)
-{
- return &_loongarch_data.rng_data;
-}
-
#endif /* !__ASSEMBLY__ */
#endif /* __ASM_VDSO_GETRANDOM_H */
diff --git a/arch/loongarch/include/asm/vdso/gettimeofday.h b/arch/loongarch/include/asm/vdso/gettimeofday.h
index 7eb3f041af764d141b005f821593a358096874ba..88cfcf13311630ed5f1a734d23a2bc3f65d79a88 100644
--- a/arch/loongarch/include/asm/vdso/gettimeofday.h
+++ b/arch/loongarch/include/asm/vdso/gettimeofday.h
@@ -72,7 +72,7 @@ static __always_inline int clock_getres_fallback(
}
static __always_inline u64 __arch_get_hw_counter(s32 clock_mode,
- const struct vdso_data *vd)
+ const struct vdso_time_data *vd)
{
uint64_t count;
@@ -89,18 +89,6 @@ static inline bool loongarch_vdso_hres_capable(void)
}
#define __arch_vdso_hres_capable loongarch_vdso_hres_capable
-static __always_inline const struct vdso_data *__arch_get_vdso_data(void)
-{
- return _vdso_data;
-}
-
-#ifdef CONFIG_TIME_NS
-static __always_inline
-const struct vdso_data *__arch_get_timens_vdso_data(const struct vdso_data *vd)
-{
- return _timens_data;
-}
-#endif
#endif /* !__ASSEMBLY__ */
#endif /* __ASM_VDSO_GETTIMEOFDAY_H */
diff --git a/arch/loongarch/include/asm/vdso/vdso.h b/arch/loongarch/include/asm/vdso/vdso.h
index 1c183a9b2115a29a997ec8db0e788d87fb191dce..50c65fb29dafb464f36615f49db8954ee0a775e3 100644
--- a/arch/loongarch/include/asm/vdso/vdso.h
+++ b/arch/loongarch/include/asm/vdso/vdso.h
@@ -12,43 +12,9 @@
#include <asm/asm.h>
#include <asm/page.h>
#include <asm/vdso.h>
+#include <vdso/datapage.h>
-struct vdso_pcpu_data {
- u32 node;
-} ____cacheline_aligned_in_smp;
-
-struct loongarch_vdso_data {
- struct vdso_pcpu_data pdata[NR_CPUS];
- struct vdso_rng_data rng_data;
-};
-
-/*
- * The layout of vvar:
- *
- * high
- * +---------------------+--------------------------+
- * | loongarch vdso data | LOONGARCH_VDSO_DATA_SIZE |
- * +---------------------+--------------------------+
- * | time-ns vdso data | PAGE_SIZE |
- * +---------------------+--------------------------+
- * | generic vdso data | PAGE_SIZE |
- * +---------------------+--------------------------+
- * low
- */
-#define LOONGARCH_VDSO_DATA_SIZE PAGE_ALIGN(sizeof(struct loongarch_vdso_data))
-#define LOONGARCH_VDSO_DATA_PAGES (LOONGARCH_VDSO_DATA_SIZE >> PAGE_SHIFT)
-
-enum vvar_pages {
- VVAR_GENERIC_PAGE_OFFSET,
- VVAR_TIMENS_PAGE_OFFSET,
- VVAR_LOONGARCH_PAGES_START,
- VVAR_LOONGARCH_PAGES_END = VVAR_LOONGARCH_PAGES_START + LOONGARCH_VDSO_DATA_PAGES - 1,
- VVAR_NR_PAGES,
-};
-
-#define VVAR_SIZE (VVAR_NR_PAGES << PAGE_SHIFT)
-
-extern struct loongarch_vdso_data _loongarch_data __attribute__((visibility("hidden")));
+#define VVAR_SIZE (VDSO_NR_PAGES << PAGE_SHIFT)
#endif /* __ASSEMBLY__ */
diff --git a/arch/loongarch/include/asm/vdso/vsyscall.h b/arch/loongarch/include/asm/vdso/vsyscall.h
index 8987e951d0a93c34ca75de676fb9c191ff4ef3c2..1140b54b4bc8278d7a322036cd9f84f71258f246 100644
--- a/arch/loongarch/include/asm/vdso/vsyscall.h
+++ b/arch/loongarch/include/asm/vdso/vsyscall.h
@@ -6,23 +6,6 @@
#include <vdso/datapage.h>
-extern struct vdso_data *vdso_data;
-extern struct vdso_rng_data *vdso_rng_data;
-
-static __always_inline
-struct vdso_data *__loongarch_get_k_vdso_data(void)
-{
- return vdso_data;
-}
-#define __arch_get_k_vdso_data __loongarch_get_k_vdso_data
-
-static __always_inline
-struct vdso_rng_data *__loongarch_get_k_vdso_rng_data(void)
-{
- return vdso_rng_data;
-}
-#define __arch_get_k_vdso_rng_data __loongarch_get_k_vdso_rng_data
-
/* The asm-generic header needs to be included after the definitions above */
#include <asm-generic/vdso/vsyscall.h>
diff --git a/arch/loongarch/kernel/asm-offsets.c b/arch/loongarch/kernel/asm-offsets.c
index 049c5c3e370cbb00fdaf6730f7777847c7325fb4..7dcf4980dbead0249ef4daeab431c7d482abfeb5 100644
--- a/arch/loongarch/kernel/asm-offsets.c
+++ b/arch/loongarch/kernel/asm-offsets.c
@@ -327,6 +327,6 @@ static void __used output_vdso_defines(void)
{
COMMENT("LoongArch vDSO offsets.");
- DEFINE(__VVAR_PAGES, VVAR_NR_PAGES);
+ DEFINE(__VDSO_PAGES, VDSO_NR_PAGES);
BLANK();
}
diff --git a/arch/loongarch/kernel/vdso.c b/arch/loongarch/kernel/vdso.c
index 05e5fbac102a902016e633db75d9aff7ed550c50..10cf1608c7b32f8e03bc2c942b51413cf8b9c505 100644
--- a/arch/loongarch/kernel/vdso.c
+++ b/arch/loongarch/kernel/vdso.c
@@ -14,7 +14,7 @@
#include <linux/random.h>
#include <linux/sched.h>
#include <linux/slab.h>
-#include <linux/time_namespace.h>
+#include <linux/vdso_datastore.h>
#include <asm/page.h>
#include <asm/vdso.h>
@@ -25,18 +25,6 @@
extern char vdso_start[], vdso_end[];
-/* Kernel-provided data used by the VDSO. */
-static union vdso_data_store generic_vdso_data __page_aligned_data;
-
-static union {
- u8 page[LOONGARCH_VDSO_DATA_SIZE];
- struct loongarch_vdso_data vdata;
-} loongarch_vdso_data __page_aligned_data;
-
-struct vdso_data *vdso_data = generic_vdso_data.data;
-struct vdso_pcpu_data *vdso_pdata = loongarch_vdso_data.vdata.pdata;
-struct vdso_rng_data *vdso_rng_data = &loongarch_vdso_data.vdata.rng_data;
-
static int vdso_mremap(const struct vm_special_mapping *sm, struct vm_area_struct *new_vma)
{
current->mm->context.vdso = (void *)(new_vma->vm_start);
@@ -44,53 +32,12 @@ static int vdso_mremap(const struct vm_special_mapping *sm, struct vm_area_struc
return 0;
}
-static vm_fault_t vvar_fault(const struct vm_special_mapping *sm,
- struct vm_area_struct *vma, struct vm_fault *vmf)
-{
- unsigned long pfn;
- struct page *timens_page = find_timens_vvar_page(vma);
-
- switch (vmf->pgoff) {
- case VVAR_GENERIC_PAGE_OFFSET:
- if (!timens_page)
- pfn = sym_to_pfn(vdso_data);
- else
- pfn = page_to_pfn(timens_page);
- break;
-#ifdef CONFIG_TIME_NS
- case VVAR_TIMENS_PAGE_OFFSET:
- /*
- * If a task belongs to a time namespace then a namespace specific
- * VVAR is mapped with the VVAR_GENERIC_PAGE_OFFSET and the real
- * VVAR page is mapped with the VVAR_TIMENS_PAGE_OFFSET offset.
- * See also the comment near timens_setup_vdso_data().
- */
- if (!timens_page)
- return VM_FAULT_SIGBUS;
- else
- pfn = sym_to_pfn(vdso_data);
- break;
-#endif /* CONFIG_TIME_NS */
- case VVAR_LOONGARCH_PAGES_START ... VVAR_LOONGARCH_PAGES_END:
- pfn = sym_to_pfn(&loongarch_vdso_data) + vmf->pgoff - VVAR_LOONGARCH_PAGES_START;
- break;
- default:
- return VM_FAULT_SIGBUS;
- }
-
- return vmf_insert_pfn(vma, vmf->address, pfn);
-}
-
struct loongarch_vdso_info vdso_info = {
.vdso = vdso_start,
.code_mapping = {
.name = "[vdso]",
.mremap = vdso_mremap,
},
- .data_mapping = {
- .name = "[vvar]",
- .fault = vvar_fault,
- },
.offset_sigreturn = vdso_offset_sigreturn,
};
@@ -101,7 +48,7 @@ static int __init init_vdso(void)
BUG_ON(!PAGE_ALIGNED(vdso_info.vdso));
for_each_possible_cpu(cpu)
- vdso_pdata[cpu].node = cpu_to_node(cpu);
+ vdso_k_arch_data->pdata[cpu].node = cpu_to_node(cpu);
vdso_info.size = PAGE_ALIGN(vdso_end - vdso_start);
vdso_info.code_mapping.pages =
@@ -115,37 +62,6 @@ static int __init init_vdso(void)
}
subsys_initcall(init_vdso);
-#ifdef CONFIG_TIME_NS
-struct vdso_data *arch_get_vdso_data(void *vvar_page)
-{
- return (struct vdso_data *)(vvar_page);
-}
-
-/*
- * The vvar mapping contains data for a specific time namespace, so when a
- * task changes namespace we must unmap its vvar data for the old namespace.
- * Subsequent faults will map in data for the new namespace.
- *
- * For more details see timens_setup_vdso_data().
- */
-int vdso_join_timens(struct task_struct *task, struct time_namespace *ns)
-{
- struct mm_struct *mm = task->mm;
- struct vm_area_struct *vma;
-
- VMA_ITERATOR(vmi, mm, 0);
-
- mmap_read_lock(mm);
- for_each_vma(vmi, vma) {
- if (vma_is_special_mapping(vma, &vdso_info.data_mapping))
- zap_vma_pages(vma);
- }
- mmap_read_unlock(mm);
-
- return 0;
-}
-#endif
-
static unsigned long vdso_base(void)
{
unsigned long base = STACK_TOP;
@@ -181,9 +97,7 @@ int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
goto out;
}
- vma = _install_special_mapping(mm, data_addr, VVAR_SIZE,
- VM_READ | VM_MAYREAD | VM_PFNMAP,
- &info->data_mapping);
+ vma = vdso_install_vvar_mapping(mm, data_addr);
if (IS_ERR(vma)) {
ret = PTR_ERR(vma);
goto out;
diff --git a/arch/loongarch/vdso/vdso.lds.S b/arch/loongarch/vdso/vdso.lds.S
index 160cfaef2de45b1243502c7356f8a913658548fe..8ff98649994750e74b30a91270d9d9ea2ba751e8 100644
--- a/arch/loongarch/vdso/vdso.lds.S
+++ b/arch/loongarch/vdso/vdso.lds.S
@@ -5,6 +5,7 @@
*/
#include <asm/page.h>
#include <generated/asm-offsets.h>
+#include <vdso/datapage.h>
OUTPUT_FORMAT("elf64-loongarch", "elf64-loongarch", "elf64-loongarch")
@@ -12,11 +13,8 @@ OUTPUT_ARCH(loongarch)
SECTIONS
{
- PROVIDE(_vdso_data = . - __VVAR_PAGES * PAGE_SIZE);
-#ifdef CONFIG_TIME_NS
- PROVIDE(_timens_data = _vdso_data + PAGE_SIZE);
-#endif
- PROVIDE(_loongarch_data = _vdso_data + 2 * PAGE_SIZE);
+ VDSO_VVAR_SYMS
+
. = SIZEOF_HEADERS;
.hash : { *(.hash) } :text
diff --git a/arch/loongarch/vdso/vgetcpu.c b/arch/loongarch/vdso/vgetcpu.c
index 0db51258b2a7ca7e44d2eb68ea514face48393f7..3798eebdf798dfa6574a8e51d6f58c206725c312 100644
--- a/arch/loongarch/vdso/vgetcpu.c
+++ b/arch/loongarch/vdso/vgetcpu.c
@@ -19,11 +19,6 @@ static __always_inline int read_cpu_id(void)
return cpu_id;
}
-static __always_inline const struct vdso_pcpu_data *get_pcpu_data(void)
-{
- return _loongarch_data.pdata;
-}
-
extern
int __vdso_getcpu(unsigned int *cpu, unsigned int *node, struct getcpu_cache *unused);
int __vdso_getcpu(unsigned int *cpu, unsigned int *node, struct getcpu_cache *unused)
@@ -37,7 +32,7 @@ int __vdso_getcpu(unsigned int *cpu, unsigned int *node, struct getcpu_cache *un
*cpu = cpu_id;
if (node) {
- data = get_pcpu_data();
+ data = __arch_get_vdso_u_arch_data()->pdata;
*node = data[cpu_id].node;
}
--
2.47.1
^ permalink raw reply related [flat|nested] 29+ messages in thread* [PATCH 09/17] arm: vdso: Switch to generic storage implementation
2024-12-16 14:09 [PATCH 00/17] vDSO: Introduce generic data storage Thomas Weißschuh
` (7 preceding siblings ...)
2024-12-16 14:10 ` [PATCH 08/17] LoongArch: vDSO: " Thomas Weißschuh
@ 2024-12-16 14:10 ` Thomas Weißschuh
2024-12-16 14:10 ` [PATCH 10/17] s390/vdso: " Thomas Weißschuh
` (7 subsequent siblings)
16 siblings, 0 replies; 29+ messages in thread
From: Thomas Weißschuh @ 2024-12-16 14:10 UTC (permalink / raw)
To: James E.J. Bottomley, Helge Deller, Andy Lutomirski,
Thomas Gleixner, Vincenzo Frascino, Anna-Maria Behnsen,
Frederic Weisbecker, Andrew Morton, Catalin Marinas, Will Deacon,
Theodore Ts'o, Jason A. Donenfeld, Paul Walmsley,
Palmer Dabbelt, Albert Ou, Huacai Chen, WANG Xuerui, Russell King,
Heiko Carstens, Vasily Gorbik, Alexander Gordeev,
Christian Borntraeger, Sven Schnelle, Thomas Bogendoerfer,
Michael Ellerman, Nicholas Piggin, Christophe Leroy, Naveen N Rao,
Madhavan Srinivasan, Ingo Molnar, Borislav Petkov, Dave Hansen,
x86, H. Peter Anvin, Arnd Bergmann
Cc: linux-parisc, linux-kernel, linux-arm-kernel, linux-riscv,
loongarch, linux-s390, linux-mips, linuxppc-dev, linux-arch,
Nam Cao, Thomas Weißschuh
The generic storage implementation provides the same features as the
custom one. However it can be shared between architectures, making
maintenance easier.
Co-developed-by: Nam Cao <namcao@linutronix.de>
Signed-off-by: Nam Cao <namcao@linutronix.de>
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
---
arch/arm/include/asm/vdso.h | 2 ++
arch/arm/include/asm/vdso/gettimeofday.h | 7 +------
arch/arm/include/asm/vdso/vsyscall.h | 12 ++---------
arch/arm/kernel/asm-offsets.c | 4 ----
arch/arm/kernel/vdso.c | 34 +++++++-------------------------
arch/arm/mm/Kconfig | 1 +
arch/arm/vdso/vdso.lds.S | 4 ++--
7 files changed, 15 insertions(+), 49 deletions(-)
diff --git a/arch/arm/include/asm/vdso.h b/arch/arm/include/asm/vdso.h
index 5b85889f82eeb422400c039e8b5e8a2a6d4553b3..88364a6727ffce224edd35dd62db1693ae5fcb1c 100644
--- a/arch/arm/include/asm/vdso.h
+++ b/arch/arm/include/asm/vdso.h
@@ -4,6 +4,8 @@
#ifdef __KERNEL__
+#define __VDSO_PAGES 4
+
#ifndef __ASSEMBLY__
struct mm_struct;
diff --git a/arch/arm/include/asm/vdso/gettimeofday.h b/arch/arm/include/asm/vdso/gettimeofday.h
index 592d3d015ca7298b3bc35871387dbb3e7f819827..1e9f81639c88cc23cae7cf267bf4674c6d6acec0 100644
--- a/arch/arm/include/asm/vdso/gettimeofday.h
+++ b/arch/arm/include/asm/vdso/gettimeofday.h
@@ -112,7 +112,7 @@ static inline bool arm_vdso_hres_capable(void)
#define __arch_vdso_hres_capable arm_vdso_hres_capable
static __always_inline u64 __arch_get_hw_counter(int clock_mode,
- const struct vdso_data *vd)
+ const struct vdso_time_data *vd)
{
#ifdef CONFIG_ARM_ARCH_TIMER
u64 cycle_now;
@@ -135,11 +135,6 @@ static __always_inline u64 __arch_get_hw_counter(int clock_mode,
#endif
}
-static __always_inline const struct vdso_data *__arch_get_vdso_data(void)
-{
- return _vdso_data;
-}
-
#endif /* !__ASSEMBLY__ */
#endif /* __ASM_VDSO_GETTIMEOFDAY_H */
diff --git a/arch/arm/include/asm/vdso/vsyscall.h b/arch/arm/include/asm/vdso/vsyscall.h
index 705414710dcdbfa9a97c344806bd079c08368801..6fe8f7113e9e533a8b7582f71611372c8db3b11f 100644
--- a/arch/arm/include/asm/vdso/vsyscall.h
+++ b/arch/arm/include/asm/vdso/vsyscall.h
@@ -7,22 +7,14 @@
#include <vdso/datapage.h>
#include <asm/cacheflush.h>
-extern struct vdso_data *vdso_data;
extern bool cntvct_ok;
static __always_inline
-struct vdso_data *__arm_get_k_vdso_data(void)
-{
- return vdso_data;
-}
-#define __arch_get_k_vdso_data __arm_get_k_vdso_data
-
-static __always_inline
-void __arm_sync_vdso_data(struct vdso_data *vdata)
+void __arm_sync_vdso_time_data(struct vdso_time_data *vdata)
{
flush_dcache_page(virt_to_page(vdata));
}
-#define __arch_sync_vdso_data __arm_sync_vdso_data
+#define __arch_sync_vdso_data __arm_sync_vdso_time_data
/* The asm-generic header needs to be included after the definitions above */
#include <asm-generic/vdso/vsyscall.h>
diff --git a/arch/arm/kernel/asm-offsets.c b/arch/arm/kernel/asm-offsets.c
index 4853875740d0fe61c6bbc32ddd9a16fa8d1fb530..123f4a8ef44660a39c4eff2a6e5fd86cb48fb572 100644
--- a/arch/arm/kernel/asm-offsets.c
+++ b/arch/arm/kernel/asm-offsets.c
@@ -153,10 +153,6 @@ int main(void)
DEFINE(CACHE_WRITEBACK_ORDER, __CACHE_WRITEBACK_ORDER);
DEFINE(CACHE_WRITEBACK_GRANULE, __CACHE_WRITEBACK_GRANULE);
BLANK();
-#ifdef CONFIG_VDSO
- DEFINE(VDSO_DATA_SIZE, sizeof(union vdso_data_store));
-#endif
- BLANK();
#ifdef CONFIG_ARM_MPU
DEFINE(MPU_RNG_INFO_RNGS, offsetof(struct mpu_rgn_info, rgns));
DEFINE(MPU_RNG_INFO_USED, offsetof(struct mpu_rgn_info, used));
diff --git a/arch/arm/kernel/vdso.c b/arch/arm/kernel/vdso.c
index 29dd2f3c62fec64c7f290468421bfad1e739c667..325448ffbba0c29895ea5d97e60d6f51e552cb2e 100644
--- a/arch/arm/kernel/vdso.c
+++ b/arch/arm/kernel/vdso.c
@@ -7,6 +7,7 @@
*/
#include <linux/cache.h>
+#include <linux/vdso_datastore.h>
#include <linux/elf.h>
#include <linux/err.h>
#include <linux/kernel.h>
@@ -33,15 +34,6 @@ extern char vdso_start[], vdso_end[];
/* Total number of pages needed for the data and text portions of the VDSO. */
unsigned int vdso_total_pages __ro_after_init;
-static union vdso_data_store vdso_data_store __page_aligned_data;
-struct vdso_data *vdso_data = vdso_data_store.data;
-
-static struct page *vdso_data_page __ro_after_init;
-static const struct vm_special_mapping vdso_data_mapping = {
- .name = "[vvar]",
- .pages = &vdso_data_page,
-};
-
static int vdso_mremap(const struct vm_special_mapping *sm,
struct vm_area_struct *new_vma)
{
@@ -192,9 +184,6 @@ static int __init vdso_init(void)
if (vdso_text_pagelist == NULL)
return -ENOMEM;
- /* Grab the VDSO data page. */
- vdso_data_page = virt_to_page(vdso_data);
-
/* Grab the VDSO text pages. */
for (i = 0; i < text_pages; i++) {
struct page *page;
@@ -205,7 +194,7 @@ static int __init vdso_init(void)
vdso_text_mapping.pages = vdso_text_pagelist;
- vdso_total_pages = 1; /* for the data/vvar page */
+ vdso_total_pages = VDSO_NR_PAGES; /* for the data/vvar pages */
vdso_total_pages += text_pages;
cntvct_ok = cntvct_functional();
@@ -216,16 +205,7 @@ static int __init vdso_init(void)
}
arch_initcall(vdso_init);
-static int install_vvar(struct mm_struct *mm, unsigned long addr)
-{
- struct vm_area_struct *vma;
-
- vma = _install_special_mapping(mm, addr, PAGE_SIZE,
- VM_READ | VM_MAYREAD,
- &vdso_data_mapping);
-
- return PTR_ERR_OR_ZERO(vma);
-}
+static_assert(__VDSO_PAGES == VDSO_NR_PAGES);
/* assumes mmap_lock is write-locked */
void arm_install_vdso(struct mm_struct *mm, unsigned long addr)
@@ -238,12 +218,12 @@ void arm_install_vdso(struct mm_struct *mm, unsigned long addr)
if (vdso_text_pagelist == NULL)
return;
- if (install_vvar(mm, addr))
+ if (IS_ERR(vdso_install_vvar_mapping(mm, addr)))
return;
- /* Account for vvar page. */
- addr += PAGE_SIZE;
- len = (vdso_total_pages - 1) << PAGE_SHIFT;
+ /* Account for vvar pages. */
+ addr += VDSO_NR_PAGES * PAGE_SIZE;
+ len = (vdso_total_pages - VDSO_NR_PAGES) << PAGE_SHIFT;
vma = _install_special_mapping(mm, addr, len,
VM_READ | VM_EXEC | VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC,
diff --git a/arch/arm/mm/Kconfig b/arch/arm/mm/Kconfig
index 2b6f50dd547840adecbe08e684ed8f1a032cd7c2..5c1023a6d78c1b4db67b2d62b71af5a79b7e701f 100644
--- a/arch/arm/mm/Kconfig
+++ b/arch/arm/mm/Kconfig
@@ -928,6 +928,7 @@ config VDSO
select GENERIC_TIME_VSYSCALL
select GENERIC_VDSO_32
select GENERIC_GETTIMEOFDAY
+ select GENERIC_VDSO_DATA_STORE
help
Place in the process address space an ELF shared object
providing fast implementations of gettimeofday and
diff --git a/arch/arm/vdso/vdso.lds.S b/arch/arm/vdso/vdso.lds.S
index 9bfa0f52923c851b6b9e96d4dbb51eb3d5d0960a..7c08371f440027f9a52e9fffae530d7db05b7c43 100644
--- a/arch/arm/vdso/vdso.lds.S
+++ b/arch/arm/vdso/vdso.lds.S
@@ -11,16 +11,16 @@
*/
#include <linux/const.h>
-#include <asm/asm-offsets.h>
#include <asm/page.h>
#include <asm/vdso.h>
+#include <vdso/datapage.h>
OUTPUT_FORMAT("elf32-littlearm", "elf32-bigarm", "elf32-littlearm")
OUTPUT_ARCH(arm)
SECTIONS
{
- PROVIDE(_vdso_data = . - VDSO_DATA_SIZE);
+ VDSO_VVAR_SYMS
. = SIZEOF_HEADERS;
--
2.47.1
^ permalink raw reply related [flat|nested] 29+ messages in thread* [PATCH 10/17] s390/vdso: Switch to generic storage implementation
2024-12-16 14:09 [PATCH 00/17] vDSO: Introduce generic data storage Thomas Weißschuh
` (8 preceding siblings ...)
2024-12-16 14:10 ` [PATCH 09/17] arm: vdso: " Thomas Weißschuh
@ 2024-12-16 14:10 ` Thomas Weißschuh
2025-01-09 11:55 ` Heiko Carstens
2024-12-16 14:10 ` [PATCH 11/17] MIPS: vdso: " Thomas Weißschuh
` (6 subsequent siblings)
16 siblings, 1 reply; 29+ messages in thread
From: Thomas Weißschuh @ 2024-12-16 14:10 UTC (permalink / raw)
To: James E.J. Bottomley, Helge Deller, Andy Lutomirski,
Thomas Gleixner, Vincenzo Frascino, Anna-Maria Behnsen,
Frederic Weisbecker, Andrew Morton, Catalin Marinas, Will Deacon,
Theodore Ts'o, Jason A. Donenfeld, Paul Walmsley,
Palmer Dabbelt, Albert Ou, Huacai Chen, WANG Xuerui, Russell King,
Heiko Carstens, Vasily Gorbik, Alexander Gordeev,
Christian Borntraeger, Sven Schnelle, Thomas Bogendoerfer,
Michael Ellerman, Nicholas Piggin, Christophe Leroy, Naveen N Rao,
Madhavan Srinivasan, Ingo Molnar, Borislav Petkov, Dave Hansen,
x86, H. Peter Anvin, Arnd Bergmann
Cc: linux-parisc, linux-kernel, linux-arm-kernel, linux-riscv,
loongarch, linux-s390, linux-mips, linuxppc-dev, linux-arch,
Nam Cao, Thomas Weißschuh
The generic storage implementation provides the same features as the
custom one. However it can be shared between architectures, making
maintenance easier.
Co-developed-by: Nam Cao <namcao@linutronix.de>
Signed-off-by: Nam Cao <namcao@linutronix.de>
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
---
arch/s390/Kconfig | 1 +
arch/s390/include/asm/vdso.h | 4 +-
arch/s390/include/asm/vdso/getrandom.h | 12 ----
arch/s390/include/asm/vdso/gettimeofday.h | 15 +----
arch/s390/include/asm/vdso/vsyscall.h | 20 -------
arch/s390/kernel/time.c | 6 +-
arch/s390/kernel/vdso.c | 97 ++-----------------------------
arch/s390/kernel/vdso32/vdso32.lds.S | 7 +--
arch/s390/kernel/vdso64/vdso64.lds.S | 8 +--
9 files changed, 17 insertions(+), 153 deletions(-)
diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig
index 0077969170e8b4ca4c99e87ec75f6ea94f3e8e00..6472eb4c210f378eaa61ddff04a6abc2f4aa2940 100644
--- a/arch/s390/Kconfig
+++ b/arch/s390/Kconfig
@@ -158,6 +158,7 @@ config S390
select GENERIC_PTDUMP
select GENERIC_SMP_IDLE_THREAD
select GENERIC_TIME_VSYSCALL
+ select GENERIC_VDSO_DATA_STORE
select GENERIC_VDSO_TIME_NS
select GENERIC_IOREMAP if PCI
select HAVE_ALIGNED_STRUCT_PAGE
diff --git a/arch/s390/include/asm/vdso.h b/arch/s390/include/asm/vdso.h
index 92c73e4d97a93a90cb640d44fca9856f93e0be14..420a073fdde5db92cfe84bb1f17a549f333f94e0 100644
--- a/arch/s390/include/asm/vdso.h
+++ b/arch/s390/include/asm/vdso.h
@@ -6,13 +6,11 @@
#ifndef __ASSEMBLY__
-extern struct vdso_data *vdso_data;
-
int vdso_getcpu_init(void);
#endif /* __ASSEMBLY__ */
-#define __VVAR_PAGES 2
+#define __VDSO_PAGES 4
#define VDSO_VERSION_STRING LINUX_2.6.29
diff --git a/arch/s390/include/asm/vdso/getrandom.h b/arch/s390/include/asm/vdso/getrandom.h
index 36355af7160bee4f04f5177cfa21283699bee006..f8713ce39bb2f2081c3bb5a42eddccc3cddc40c8 100644
--- a/arch/s390/include/asm/vdso/getrandom.h
+++ b/arch/s390/include/asm/vdso/getrandom.h
@@ -23,18 +23,6 @@ static __always_inline ssize_t getrandom_syscall(void *buffer, size_t len, unsig
return syscall3(__NR_getrandom, (long)buffer, (long)len, (long)flags);
}
-static __always_inline const struct vdso_rng_data *__arch_get_vdso_rng_data(void)
-{
- /*
- * The RNG data is in the real VVAR data page, but if a task belongs to a time namespace
- * then VVAR_DATA_PAGE_OFFSET points to the namespace-specific VVAR page and VVAR_TIMENS_
- * PAGE_OFFSET points to the real VVAR page.
- */
- if (IS_ENABLED(CONFIG_TIME_NS) && _vdso_data->clock_mode == VDSO_CLOCKMODE_TIMENS)
- return (void *)&_vdso_rng_data + VVAR_TIMENS_PAGE_OFFSET * PAGE_SIZE;
- return &_vdso_rng_data;
-}
-
#endif /* !__ASSEMBLY__ */
#endif /* __ASM_VDSO_GETRANDOM_H */
diff --git a/arch/s390/include/asm/vdso/gettimeofday.h b/arch/s390/include/asm/vdso/gettimeofday.h
index 7937765ccfa5b222931591cc5388827e5f75d1b5..fb4564308e9d77a40f8d5059503519e9f5961f14 100644
--- a/arch/s390/include/asm/vdso/gettimeofday.h
+++ b/arch/s390/include/asm/vdso/gettimeofday.h
@@ -14,12 +14,7 @@
#include <linux/compiler.h>
-static __always_inline const struct vdso_data *__arch_get_vdso_data(void)
-{
- return _vdso_data;
-}
-
-static inline u64 __arch_get_hw_counter(s32 clock_mode, const struct vdso_data *vd)
+static inline u64 __arch_get_hw_counter(s32 clock_mode, const struct vdso_time_data *vd)
{
u64 adj, now;
@@ -49,12 +44,4 @@ long clock_getres_fallback(clockid_t clkid, struct __kernel_timespec *ts)
return syscall2(__NR_clock_getres, (long)clkid, (long)ts);
}
-#ifdef CONFIG_TIME_NS
-static __always_inline
-const struct vdso_data *__arch_get_timens_vdso_data(const struct vdso_data *vd)
-{
- return _timens_data;
-}
-#endif
-
#endif
diff --git a/arch/s390/include/asm/vdso/vsyscall.h b/arch/s390/include/asm/vdso/vsyscall.h
index 3eb576ecd3bd998daf9372a52befa8b76d52f2bf..d346ebe513015e767405452cd69495ae497c91ee 100644
--- a/arch/s390/include/asm/vdso/vsyscall.h
+++ b/arch/s390/include/asm/vdso/vsyscall.h
@@ -2,32 +2,12 @@
#ifndef __ASM_VDSO_VSYSCALL_H
#define __ASM_VDSO_VSYSCALL_H
-#define __VDSO_RND_DATA_OFFSET 768
-
#ifndef __ASSEMBLY__
#include <linux/hrtimer.h>
#include <vdso/datapage.h>
#include <asm/vdso.h>
-enum vvar_pages {
- VVAR_DATA_PAGE_OFFSET,
- VVAR_TIMENS_PAGE_OFFSET,
- VVAR_NR_PAGES
-};
-
-static __always_inline struct vdso_data *__s390_get_k_vdso_data(void)
-{
- return vdso_data;
-}
-#define __arch_get_k_vdso_data __s390_get_k_vdso_data
-
-static __always_inline struct vdso_rng_data *__s390_get_k_vdso_rnd_data(void)
-{
- return (void *)vdso_data + __VDSO_RND_DATA_OFFSET;
-}
-#define __arch_get_k_vdso_rng_data __s390_get_k_vdso_rnd_data
-
/* The asm-generic header needs to be included after the definitions above */
#include <asm-generic/vdso/vsyscall.h>
diff --git a/arch/s390/kernel/time.c b/arch/s390/kernel/time.c
index 34a65c141ea076ba97b3238f1f36f077b15961df..a227621652ad682532cb2cc763f6cfe4368fe3d3 100644
--- a/arch/s390/kernel/time.c
+++ b/arch/s390/kernel/time.c
@@ -84,7 +84,7 @@ void __init time_early_init(void)
/* Initialize TOD steering parameters */
tod_steering_end = tod_clock_base.tod;
for (cs = 0; cs < CS_BASES; cs++)
- vdso_data[cs].arch_data.tod_steering_end = tod_steering_end;
+ vdso_k_time_data[cs].arch_data.tod_steering_end = tod_steering_end;
if (!test_facility(28))
return;
@@ -390,8 +390,8 @@ static void clock_sync_global(long delta)
tod_steering_delta);
tod_steering_end = now + (abs(tod_steering_delta) << 15);
for (cs = 0; cs < CS_BASES; cs++) {
- vdso_data[cs].arch_data.tod_steering_end = tod_steering_end;
- vdso_data[cs].arch_data.tod_steering_delta = tod_steering_delta;
+ vdso_k_time_data[cs].arch_data.tod_steering_end = tod_steering_end;
+ vdso_k_time_data[cs].arch_data.tod_steering_delta = tod_steering_delta;
}
/* Update LPAR offset. */
diff --git a/arch/s390/kernel/vdso.c b/arch/s390/kernel/vdso.c
index 598b512cde012b1857c748042ceeea65b54cb92f..70c8f9ad13cde96f0f307213bacb671b818f628b 100644
--- a/arch/s390/kernel/vdso.c
+++ b/arch/s390/kernel/vdso.c
@@ -16,8 +16,8 @@
#include <linux/mm.h>
#include <linux/slab.h>
#include <linux/smp.h>
-#include <linux/time_namespace.h>
#include <linux/random.h>
+#include <linux/vdso_datastore.h>
#include <vdso/datapage.h>
#include <asm/vdso/vsyscall.h>
#include <asm/alternative.h>
@@ -26,85 +26,6 @@
extern char vdso64_start[], vdso64_end[];
extern char vdso32_start[], vdso32_end[];
-static struct vm_special_mapping vvar_mapping;
-
-static union vdso_data_store vdso_data_store __page_aligned_data;
-
-struct vdso_data *vdso_data = vdso_data_store.data;
-
-#ifdef CONFIG_TIME_NS
-struct vdso_data *arch_get_vdso_data(void *vvar_page)
-{
- return (struct vdso_data *)(vvar_page);
-}
-
-/*
- * The VVAR page layout depends on whether a task belongs to the root or
- * non-root time namespace. Whenever a task changes its namespace, the VVAR
- * page tables are cleared and then they will be re-faulted with a
- * corresponding layout.
- * See also the comment near timens_setup_vdso_data() for details.
- */
-int vdso_join_timens(struct task_struct *task, struct time_namespace *ns)
-{
- struct mm_struct *mm = task->mm;
- VMA_ITERATOR(vmi, mm, 0);
- struct vm_area_struct *vma;
-
- mmap_read_lock(mm);
- for_each_vma(vmi, vma) {
- if (!vma_is_special_mapping(vma, &vvar_mapping))
- continue;
- zap_vma_pages(vma);
- break;
- }
- mmap_read_unlock(mm);
- return 0;
-}
-#endif
-
-static vm_fault_t vvar_fault(const struct vm_special_mapping *sm,
- struct vm_area_struct *vma, struct vm_fault *vmf)
-{
- struct page *timens_page = find_timens_vvar_page(vma);
- unsigned long addr, pfn;
- vm_fault_t err;
-
- switch (vmf->pgoff) {
- case VVAR_DATA_PAGE_OFFSET:
- pfn = virt_to_pfn(vdso_data);
- if (timens_page) {
- /*
- * Fault in VVAR page too, since it will be accessed
- * to get clock data anyway.
- */
- addr = vmf->address + VVAR_TIMENS_PAGE_OFFSET * PAGE_SIZE;
- err = vmf_insert_pfn(vma, addr, pfn);
- if (unlikely(err & VM_FAULT_ERROR))
- return err;
- pfn = page_to_pfn(timens_page);
- }
- break;
-#ifdef CONFIG_TIME_NS
- case VVAR_TIMENS_PAGE_OFFSET:
- /*
- * If a task belongs to a time namespace then a namespace
- * specific VVAR is mapped with the VVAR_DATA_PAGE_OFFSET and
- * the real VVAR page is mapped with the VVAR_TIMENS_PAGE_OFFSET
- * offset.
- * See also the comment near timens_setup_vdso_data().
- */
- if (!timens_page)
- return VM_FAULT_SIGBUS;
- pfn = virt_to_pfn(vdso_data);
- break;
-#endif /* CONFIG_TIME_NS */
- default:
- return VM_FAULT_SIGBUS;
- }
- return vmf_insert_pfn(vma, vmf->address, pfn);
-}
-
static int vdso_mremap(const struct vm_special_mapping *sm,
struct vm_area_struct *vma)
{
@@ -112,11 +33,6 @@ static int vdso_mremap(const struct vm_special_mapping *sm,
return 0;
}
-static struct vm_special_mapping vvar_mapping = {
- .name = "[vvar]",
- .fault = vvar_fault,
-};
-
static struct vm_special_mapping vdso64_mapping = {
.name = "[vdso]",
.mremap = vdso_mremap,
@@ -142,7 +58,7 @@ static int map_vdso(unsigned long addr, unsigned long vdso_mapping_len)
struct vm_area_struct *vma;
int rc;
- BUILD_BUG_ON(VVAR_NR_PAGES != __VVAR_PAGES);
+ BUILD_BUG_ON(VDSO_NR_PAGES != __VDSO_PAGES);
if (mmap_write_lock_killable(mm))
return -EINTR;
@@ -157,14 +73,11 @@ static int map_vdso(unsigned long addr, unsigned long vdso_mapping_len)
rc = vvar_start;
if (IS_ERR_VALUE(vvar_start))
goto out;
- vma = _install_special_mapping(mm, vvar_start, VVAR_NR_PAGES*PAGE_SIZE,
- VM_READ|VM_MAYREAD|VM_IO|VM_DONTDUMP|
- VM_PFNMAP,
- &vvar_mapping);
+ vma = vdso_install_vvar_mapping(mm, vvar_start);
rc = PTR_ERR(vma);
if (IS_ERR(vma))
goto out;
- vdso_text_start = vvar_start + VVAR_NR_PAGES * PAGE_SIZE;
+ vdso_text_start = vvar_start + VDSO_NR_PAGES * PAGE_SIZE;
/* VM_MAYWRITE for COW so gdb can set breakpoints */
vma = _install_special_mapping(mm, vdso_text_start, vdso_text_len,
VM_READ|VM_EXEC|
@@ -220,7 +133,7 @@ unsigned long vdso_text_size(void)
unsigned long vdso_size(void)
{
- return vdso_text_size() + VVAR_NR_PAGES * PAGE_SIZE;
+ return vdso_text_size() + VDSO_NR_PAGES * PAGE_SIZE;
}
int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
diff --git a/arch/s390/kernel/vdso32/vdso32.lds.S b/arch/s390/kernel/vdso32/vdso32.lds.S
index c916c4f73f766ebcc9328b189e46015e67393b0d..9630d58c20806b51f3a2f3b59a53409ad6d3508f 100644
--- a/arch/s390/kernel/vdso32/vdso32.lds.S
+++ b/arch/s390/kernel/vdso32/vdso32.lds.S
@@ -6,16 +6,15 @@
#include <asm/page.h>
#include <asm/vdso.h>
+#include <vdso/datapage.h>
OUTPUT_FORMAT("elf32-s390", "elf32-s390", "elf32-s390")
OUTPUT_ARCH(s390:31-bit)
SECTIONS
{
- PROVIDE(_vdso_data = . - __VVAR_PAGES * PAGE_SIZE);
-#ifdef CONFIG_TIME_NS
- PROVIDE(_timens_data = _vdso_data + PAGE_SIZE);
-#endif
+ VDSO_VVAR_SYMS
+
. = SIZEOF_HEADERS;
.hash : { *(.hash) } :text
diff --git a/arch/s390/kernel/vdso64/vdso64.lds.S b/arch/s390/kernel/vdso64/vdso64.lds.S
index ec42b7d9cb53094b783c6b0492962af7e5027831..e4f6551ae898881baff6d37701a9d8d9188a52cc 100644
--- a/arch/s390/kernel/vdso64/vdso64.lds.S
+++ b/arch/s390/kernel/vdso64/vdso64.lds.S
@@ -7,17 +7,15 @@
#include <asm/vdso/vsyscall.h>
#include <asm/page.h>
#include <asm/vdso.h>
+#include <vdso/datapage.h>
OUTPUT_FORMAT("elf64-s390", "elf64-s390", "elf64-s390")
OUTPUT_ARCH(s390:64-bit)
SECTIONS
{
- PROVIDE(_vdso_data = . - __VVAR_PAGES * PAGE_SIZE);
- PROVIDE(_vdso_rng_data = _vdso_data + __VDSO_RND_DATA_OFFSET);
-#ifdef CONFIG_TIME_NS
- PROVIDE(_timens_data = _vdso_data + PAGE_SIZE);
-#endif
+ VDSO_VVAR_SYMS
+
. = SIZEOF_HEADERS;
.hash : { *(.hash) } :text
--
2.47.1
^ permalink raw reply related [flat|nested] 29+ messages in thread* Re: [PATCH 10/17] s390/vdso: Switch to generic storage implementation
2024-12-16 14:10 ` [PATCH 10/17] s390/vdso: " Thomas Weißschuh
@ 2025-01-09 11:55 ` Heiko Carstens
0 siblings, 0 replies; 29+ messages in thread
From: Heiko Carstens @ 2025-01-09 11:55 UTC (permalink / raw)
To: Thomas Weißschuh
Cc: James E.J. Bottomley, Helge Deller, Andy Lutomirski,
Thomas Gleixner, Vincenzo Frascino, Anna-Maria Behnsen,
Frederic Weisbecker, Andrew Morton, Catalin Marinas, Will Deacon,
Theodore Ts'o, Jason A. Donenfeld, Paul Walmsley,
Palmer Dabbelt, Albert Ou, Huacai Chen, WANG Xuerui, Russell King,
Vasily Gorbik, Alexander Gordeev, Christian Borntraeger,
Sven Schnelle, Thomas Bogendoerfer, Michael Ellerman,
Nicholas Piggin, Christophe Leroy, Naveen N Rao,
Madhavan Srinivasan, Ingo Molnar, Borislav Petkov, Dave Hansen,
x86, H. Peter Anvin, Arnd Bergmann, linux-parisc, linux-kernel,
linux-arm-kernel, linux-riscv, loongarch, linux-s390, linux-mips,
linuxppc-dev, linux-arch, Nam Cao
On Mon, Dec 16, 2024 at 03:10:06PM +0100, Thomas Weißschuh wrote:
> The generic storage implementation provides the same features as the
> custom one. However it can be shared between architectures, making
> maintenance easier.
>
> Co-developed-by: Nam Cao <namcao@linutronix.de>
> Signed-off-by: Nam Cao <namcao@linutronix.de>
> Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
> ---
> arch/s390/Kconfig | 1 +
> arch/s390/include/asm/vdso.h | 4 +-
> arch/s390/include/asm/vdso/getrandom.h | 12 ----
> arch/s390/include/asm/vdso/gettimeofday.h | 15 +----
> arch/s390/include/asm/vdso/vsyscall.h | 20 -------
> arch/s390/kernel/time.c | 6 +-
> arch/s390/kernel/vdso.c | 97 ++-----------------------------
> arch/s390/kernel/vdso32/vdso32.lds.S | 7 +--
> arch/s390/kernel/vdso64/vdso64.lds.S | 8 +--
> 9 files changed, 17 insertions(+), 153 deletions(-)
Looks good to me and works.
Acked-by: Heiko Carstens <hca@linux.ibm.com>
^ permalink raw reply [flat|nested] 29+ messages in thread
* [PATCH 11/17] MIPS: vdso: Switch to generic storage implementation
2024-12-16 14:09 [PATCH 00/17] vDSO: Introduce generic data storage Thomas Weißschuh
` (9 preceding siblings ...)
2024-12-16 14:10 ` [PATCH 10/17] s390/vdso: " Thomas Weißschuh
@ 2024-12-16 14:10 ` Thomas Weißschuh
2024-12-16 14:10 ` [PATCH 12/17] powerpc/vdso: " Thomas Weißschuh
` (5 subsequent siblings)
16 siblings, 0 replies; 29+ messages in thread
From: Thomas Weißschuh @ 2024-12-16 14:10 UTC (permalink / raw)
To: James E.J. Bottomley, Helge Deller, Andy Lutomirski,
Thomas Gleixner, Vincenzo Frascino, Anna-Maria Behnsen,
Frederic Weisbecker, Andrew Morton, Catalin Marinas, Will Deacon,
Theodore Ts'o, Jason A. Donenfeld, Paul Walmsley,
Palmer Dabbelt, Albert Ou, Huacai Chen, WANG Xuerui, Russell King,
Heiko Carstens, Vasily Gorbik, Alexander Gordeev,
Christian Borntraeger, Sven Schnelle, Thomas Bogendoerfer,
Michael Ellerman, Nicholas Piggin, Christophe Leroy, Naveen N Rao,
Madhavan Srinivasan, Ingo Molnar, Borislav Petkov, Dave Hansen,
x86, H. Peter Anvin, Arnd Bergmann
Cc: linux-parisc, linux-kernel, linux-arm-kernel, linux-riscv,
loongarch, linux-s390, linux-mips, linuxppc-dev, linux-arch,
Nam Cao, Thomas Weißschuh
The generic storage implementation provides the same features as the
custom one. However it can be shared between architectures, making
maintenance easier.
Co-developed-by: Nam Cao <namcao@linutronix.de>
Signed-off-by: Nam Cao <namcao@linutronix.de>
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
---
arch/mips/Kconfig | 1 +
arch/mips/include/asm/vdso/gettimeofday.h | 9 +++---
arch/mips/include/asm/vdso/vdso.h | 19 ++++++-------
arch/mips/include/asm/vdso/vsyscall.h | 14 ++-------
arch/mips/kernel/vdso.c | 47 ++++++++++++-------------------
arch/mips/vdso/vdso.lds.S | 5 +++-
6 files changed, 38 insertions(+), 57 deletions(-)
diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig
index 467b10f4361aeb7aad0121f334eaa5d23351010c..94fae59589ae80d590ac250b52ba30e9dd6eda32 100644
--- a/arch/mips/Kconfig
+++ b/arch/mips/Kconfig
@@ -49,6 +49,7 @@ config MIPS
select GENERIC_SMP_IDLE_THREAD
select GENERIC_IDLE_POLL_SETUP
select GENERIC_TIME_VSYSCALL
+ select GENERIC_VDSO_DATA_STORE
select GUP_GET_PXX_LOW_HIGH if CPU_MIPS32 && PHYS_ADDR_T_64BIT
select HAS_IOPORT if !NO_IOPORT_MAP || ISA
select HAVE_ARCH_COMPILER_H
diff --git a/arch/mips/include/asm/vdso/gettimeofday.h b/arch/mips/include/asm/vdso/gettimeofday.h
index 44a45f3fa4b01026e39efb7f8f51051ec464340c..18220bc823f7fac5b70cfbc4c876c91e752fafaa 100644
--- a/arch/mips/include/asm/vdso/gettimeofday.h
+++ b/arch/mips/include/asm/vdso/gettimeofday.h
@@ -167,7 +167,7 @@ static __always_inline u64 read_r4k_count(void)
#ifdef CONFIG_CLKSRC_MIPS_GIC
-static __always_inline u64 read_gic_count(const struct vdso_data *data)
+static __always_inline u64 read_gic_count(const struct vdso_time_data *data)
{
void __iomem *gic = get_gic(data);
u32 hi, hi2, lo;
@@ -184,7 +184,7 @@ static __always_inline u64 read_gic_count(const struct vdso_data *data)
#endif
static __always_inline u64 __arch_get_hw_counter(s32 clock_mode,
- const struct vdso_data *vd)
+ const struct vdso_time_data *vd)
{
#ifdef CONFIG_CSRC_R4K
if (clock_mode == VDSO_CLOCKMODE_R4K)
@@ -209,10 +209,11 @@ static inline bool mips_vdso_hres_capable(void)
}
#define __arch_vdso_hres_capable mips_vdso_hres_capable
-static __always_inline const struct vdso_data *__arch_get_vdso_data(void)
+static __always_inline const struct vdso_time_data *__mips_get_vdso_u_time_data(void)
{
- return get_vdso_data();
+ return get_vdso_time_data();
}
+#define __arch_get_vdso_u_time_data __mips_get_vdso_u_time_data
#endif /* !__ASSEMBLY__ */
diff --git a/arch/mips/include/asm/vdso/vdso.h b/arch/mips/include/asm/vdso/vdso.h
index 6cd88191fefa9ce6d8323dd70d45aa9a198ac9d0..acd0efcd3d93ef7e71107302a40d24b4b51aae99 100644
--- a/arch/mips/include/asm/vdso/vdso.h
+++ b/arch/mips/include/asm/vdso/vdso.h
@@ -5,16 +5,18 @@
*/
#include <asm/sgidefs.h>
+#include <vdso/page.h>
+
+#define __VDSO_PAGES 4
#ifndef __ASSEMBLY__
#include <asm/asm.h>
-#include <asm/page.h>
#include <asm/vdso.h>
-static inline unsigned long get_vdso_base(void)
+static inline const struct vdso_time_data *get_vdso_time_data(void)
{
- unsigned long addr;
+ const struct vdso_time_data *addr;
/*
* We can't use cpu_has_mips_r6 since it needs the cpu_data[]
@@ -27,7 +29,7 @@ static inline unsigned long get_vdso_base(void)
* We can't use addiupc because there is no label-label
* support for the addiupc reloc
*/
- __asm__("lapc %0, _start \n"
+ __asm__("lapc %0, vdso_u_time_data \n"
: "=r" (addr) : :);
#else
/*
@@ -46,7 +48,7 @@ static inline unsigned long get_vdso_base(void)
" .set noreorder \n"
" bal 1f \n"
" nop \n"
- " .word _start - . \n"
+ " .word vdso_u_time_data - . \n"
"1: lw %0, 0($31) \n"
" " STR(PTR_ADDU) " %0, $31, %0 \n"
" .set pop \n"
@@ -58,14 +60,9 @@ static inline unsigned long get_vdso_base(void)
return addr;
}
-static inline const struct vdso_data *get_vdso_data(void)
-{
- return (const struct vdso_data *)(get_vdso_base() - PAGE_SIZE);
-}
-
#ifdef CONFIG_CLKSRC_MIPS_GIC
-static inline void __iomem *get_gic(const struct vdso_data *data)
+static inline void __iomem *get_gic(const struct vdso_time_data *data)
{
return (void __iomem *)((unsigned long)data & PAGE_MASK) - PAGE_SIZE;
}
diff --git a/arch/mips/include/asm/vdso/vsyscall.h b/arch/mips/include/asm/vdso/vsyscall.h
index a4582870aaea49ac288d62ec4fa1338a98621918..2b1debb62dee07bb49ab64f755ff9120d512458a 100644
--- a/arch/mips/include/asm/vdso/vsyscall.h
+++ b/arch/mips/include/asm/vdso/vsyscall.h
@@ -2,22 +2,12 @@
#ifndef __ASM_VDSO_VSYSCALL_H
#define __ASM_VDSO_VSYSCALL_H
+#include <asm/page.h>
+
#ifndef __ASSEMBLY__
#include <vdso/datapage.h>
-extern struct vdso_data *vdso_data;
-
-/*
- * Update the vDSO data page to keep in sync with kernel timekeeping.
- */
-static __always_inline
-struct vdso_data *__mips_get_k_vdso_data(void)
-{
- return vdso_data;
-}
-#define __arch_get_k_vdso_data __mips_get_k_vdso_data
-
/* The asm-generic header needs to be included after the definitions above */
#include <asm-generic/vdso/vsyscall.h>
diff --git a/arch/mips/kernel/vdso.c b/arch/mips/kernel/vdso.c
index 4c8e3c0aa210476d7b8cb349b99e9a5a453aa7ce..470bf52970c9fc17b275e4e051378f8f08ebf986 100644
--- a/arch/mips/kernel/vdso.c
+++ b/arch/mips/kernel/vdso.c
@@ -14,6 +14,7 @@
#include <linux/random.h>
#include <linux/sched.h>
#include <linux/slab.h>
+#include <linux/vdso_datastore.h>
#include <asm/abi.h>
#include <asm/mips-cps.h>
@@ -22,20 +23,7 @@
#include <vdso/helpers.h>
#include <vdso/vsyscall.h>
-/* Kernel-provided data used by the VDSO. */
-static union vdso_data_store mips_vdso_data __page_aligned_data;
-struct vdso_data *vdso_data = mips_vdso_data.data;
-
-/*
- * Mapping for the VDSO data/GIC pages. The real pages are mapped manually, as
- * what we map and where within the area they are mapped is determined at
- * runtime.
- */
-static struct page *no_pages[] = { NULL };
-static struct vm_special_mapping vdso_vvar_mapping = {
- .name = "[vvar]",
- .pages = no_pages,
-};
+static_assert(VDSO_NR_PAGES == __VDSO_PAGES);
static void __init init_vdso_image(struct mips_vdso_image *image)
{
@@ -89,7 +77,7 @@ int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
{
struct mips_vdso_image *image = current->thread.abi->vdso;
struct mm_struct *mm = current->mm;
- unsigned long gic_size, vvar_size, size, base, data_addr, vdso_addr, gic_pfn, gic_base;
+ unsigned long gic_size, size, base, data_addr, vdso_addr, gic_pfn, gic_base;
struct vm_area_struct *vma;
int ret;
@@ -117,8 +105,7 @@ int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
* the counter registers at the start.
*/
gic_size = mips_gic_present() ? PAGE_SIZE : 0;
- vvar_size = gic_size + PAGE_SIZE;
- size = vvar_size + image->size;
+ size = gic_size + VDSO_NR_PAGES * PAGE_SIZE + image->size;
/*
* Find a region that's large enough for us to perform the
@@ -141,15 +128,13 @@ int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
*/
if (cpu_has_dc_aliases) {
base = __ALIGN_MASK(base, shm_align_mask);
- base += ((unsigned long)vdso_data - gic_size) & shm_align_mask;
+ base += ((unsigned long)vdso_k_time_data - gic_size) & shm_align_mask;
}
data_addr = base + gic_size;
- vdso_addr = data_addr + PAGE_SIZE;
+ vdso_addr = data_addr + VDSO_NR_PAGES * PAGE_SIZE;
- vma = _install_special_mapping(mm, base, vvar_size,
- VM_READ | VM_MAYREAD,
- &vdso_vvar_mapping);
+ vma = vdso_install_vvar_mapping(mm, data_addr);
if (IS_ERR(vma)) {
ret = PTR_ERR(vma);
goto out;
@@ -159,6 +144,17 @@ int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
if (gic_size) {
gic_base = (unsigned long)mips_gic_base + MIPS_GIC_USER_OFS;
gic_pfn = PFN_DOWN(__pa(gic_base));
+ static const struct vm_special_mapping gic_mapping = {
+ .name = "[gic]",
+ .pages = (struct page **) { NULL },
+ };
+
+ vma = _install_special_mapping(mm, base, gic_size, VM_READ | VM_MAYREAD,
+ &gic_mapping);
+ if (IS_ERR(vma)) {
+ ret = PTR_ERR(vma);
+ goto out;
+ }
ret = io_remap_pfn_range(vma, base, gic_pfn, gic_size,
pgprot_noncached(vma->vm_page_prot));
@@ -166,13 +162,6 @@ int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
goto out;
}
- /* Map data page. */
- ret = remap_pfn_range(vma, data_addr,
- virt_to_phys(vdso_data) >> PAGE_SHIFT,
- PAGE_SIZE, vma->vm_page_prot);
- if (ret)
- goto out;
-
/* Map VDSO image. */
vma = _install_special_mapping(mm, vdso_addr, image->size,
VM_READ | VM_EXEC |
diff --git a/arch/mips/vdso/vdso.lds.S b/arch/mips/vdso/vdso.lds.S
index 836465e3bcb8a15cb3f0f96d852d2b252c9d5e2a..c8bbe56d89cb095da21ac1f56d9999914defc305 100644
--- a/arch/mips/vdso/vdso.lds.S
+++ b/arch/mips/vdso/vdso.lds.S
@@ -5,6 +5,8 @@
*/
#include <asm/sgidefs.h>
+#include <asm/vdso/vdso.h>
+#include <vdso/datapage.h>
#if _MIPS_SIM == _MIPS_SIM_ABI64
OUTPUT_FORMAT("elf64-tradlittlemips", "elf64-tradbigmips", "elf64-tradlittlemips")
@@ -18,7 +20,8 @@ OUTPUT_ARCH(mips)
SECTIONS
{
- PROVIDE(_start = .);
+ VDSO_VVAR_SYMS
+
. = SIZEOF_HEADERS;
/*
--
2.47.1
^ permalink raw reply related [flat|nested] 29+ messages in thread* [PATCH 12/17] powerpc/vdso: Switch to generic storage implementation
2024-12-16 14:09 [PATCH 00/17] vDSO: Introduce generic data storage Thomas Weißschuh
` (10 preceding siblings ...)
2024-12-16 14:10 ` [PATCH 11/17] MIPS: vdso: " Thomas Weißschuh
@ 2024-12-16 14:10 ` Thomas Weißschuh
2024-12-18 7:20 ` Christophe Leroy
2024-12-16 14:10 ` [PATCH 13/17] x86/vdso: " Thomas Weißschuh
` (4 subsequent siblings)
16 siblings, 1 reply; 29+ messages in thread
From: Thomas Weißschuh @ 2024-12-16 14:10 UTC (permalink / raw)
To: James E.J. Bottomley, Helge Deller, Andy Lutomirski,
Thomas Gleixner, Vincenzo Frascino, Anna-Maria Behnsen,
Frederic Weisbecker, Andrew Morton, Catalin Marinas, Will Deacon,
Theodore Ts'o, Jason A. Donenfeld, Paul Walmsley,
Palmer Dabbelt, Albert Ou, Huacai Chen, WANG Xuerui, Russell King,
Heiko Carstens, Vasily Gorbik, Alexander Gordeev,
Christian Borntraeger, Sven Schnelle, Thomas Bogendoerfer,
Michael Ellerman, Nicholas Piggin, Christophe Leroy, Naveen N Rao,
Madhavan Srinivasan, Ingo Molnar, Borislav Petkov, Dave Hansen,
x86, H. Peter Anvin, Arnd Bergmann
Cc: linux-parisc, linux-kernel, linux-arm-kernel, linux-riscv,
loongarch, linux-s390, linux-mips, linuxppc-dev, linux-arch,
Nam Cao, Thomas Weißschuh
The generic storage implementation provides the same features as the
custom one. However it can be shared between architectures, making
maintenance easier.
Co-developed-by: Nam Cao <namcao@linutronix.de>
Signed-off-by: Nam Cao <namcao@linutronix.de>
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
---
arch/powerpc/Kconfig | 2 +
arch/powerpc/include/asm/vdso.h | 1 +
arch/powerpc/include/asm/vdso/arch_data.h | 37 +++++++++
arch/powerpc/include/asm/vdso/getrandom.h | 11 +--
arch/powerpc/include/asm/vdso/gettimeofday.h | 36 +++++----
arch/powerpc/include/asm/vdso/vsyscall.h | 13 ---
arch/powerpc/include/asm/vdso_datapage.h | 44 +---------
arch/powerpc/kernel/asm-offsets.c | 1 -
arch/powerpc/kernel/time.c | 2 +-
arch/powerpc/kernel/vdso.c | 115 +++------------------------
arch/powerpc/kernel/vdso/cacheflush.S | 2 +-
arch/powerpc/kernel/vdso/datapage.S | 4 +-
arch/powerpc/kernel/vdso/gettimeofday.S | 4 +-
arch/powerpc/kernel/vdso/vdso32.lds.S | 4 +-
arch/powerpc/kernel/vdso/vdso64.lds.S | 4 +-
arch/powerpc/kernel/vdso/vgettimeofday.c | 14 ++--
16 files changed, 101 insertions(+), 193 deletions(-)
diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index a0ce777f97063bf858942c60654d8411bcf2a3dc..600fa3b917ee902d016f2a04376950a9dc49074f 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -156,6 +156,7 @@ config PPC
select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
select ARCH_HAS_UACCESS_FLUSHCACHE
select ARCH_HAS_UBSAN
+ select ARCH_HAS_VDSO_ARCH_DATA
select ARCH_HAVE_NMI_SAFE_CMPXCHG
select ARCH_HAVE_EXTRA_ELF_NOTES if SPU_BASE
select ARCH_KEEP_MEMBLOCK
@@ -206,6 +207,7 @@ config PPC
select GENERIC_PTDUMP
select GENERIC_SMP_IDLE_THREAD
select GENERIC_TIME_VSYSCALL
+ select GENERIC_VDSO_DATA_STORE
select GENERIC_VDSO_TIME_NS
select HAS_IOPORT if PCI
select HAVE_ARCH_AUDITSYSCALL
diff --git a/arch/powerpc/include/asm/vdso.h b/arch/powerpc/include/asm/vdso.h
index 8d972bc98b55fe916f23488ca9e2a5918046b9aa..1ca23fbfe087ae90b90c4286335f86d9f8121078 100644
--- a/arch/powerpc/include/asm/vdso.h
+++ b/arch/powerpc/include/asm/vdso.h
@@ -3,6 +3,7 @@
#define _ASM_POWERPC_VDSO_H
#define VDSO_VERSION_STRING LINUX_2.6.15
+#define __VDSO_PAGES 4
#ifndef __ASSEMBLY__
diff --git a/arch/powerpc/include/asm/vdso/arch_data.h b/arch/powerpc/include/asm/vdso/arch_data.h
new file mode 100644
index 0000000000000000000000000000000000000000..c240a6b875181ac4159f2e80b11f9bf214e22808
--- /dev/null
+++ b/arch/powerpc/include/asm/vdso/arch_data.h
@@ -0,0 +1,37 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2002 Peter Bergner <bergner@vnet.ibm.com>, IBM
+ * Copyright (C) 2005 Benjamin Herrenschmidy <benh@kernel.crashing.org>,
+ * IBM Corp.
+ */
+#ifndef _ASM_POWERPC_VDSO_ARCH_DATA_H
+#define _ASM_POWERPC_VDSO_ARCH_DATA_H
+
+#include <linux/unistd.h>
+#include <linux/types.h>
+
+#define SYSCALL_MAP_SIZE ((NR_syscalls + 31) / 32)
+
+#ifdef CONFIG_PPC64
+
+struct vdso_arch_data {
+ __u64 tb_ticks_per_sec; /* Timebase tics / sec */
+ __u32 dcache_block_size; /* L1 d-cache block size */
+ __u32 icache_block_size; /* L1 i-cache block size */
+ __u32 dcache_log_block_size; /* L1 d-cache log block size */
+ __u32 icache_log_block_size; /* L1 i-cache log block size */
+ __u32 syscall_map[SYSCALL_MAP_SIZE]; /* Map of syscalls */
+ __u32 compat_syscall_map[SYSCALL_MAP_SIZE]; /* Map of compat syscalls */
+};
+
+#else /* CONFIG_PPC64 */
+
+struct vdso_arch_data {
+ __u64 tb_ticks_per_sec; /* Timebase tics / sec */
+ __u32 syscall_map[SYSCALL_MAP_SIZE]; /* Map of syscalls */
+ __u32 compat_syscall_map[0]; /* No compat syscalls on PPC32 */
+};
+
+#endif /* CONFIG_PPC64 */
+
+#endif /* _ASM_POWERPC_VDSO_ARCH_DATA_H */
diff --git a/arch/powerpc/include/asm/vdso/getrandom.h b/arch/powerpc/include/asm/vdso/getrandom.h
index 80ce0709725eb89c1f3b69e0733038b458fbf24f..c82eb0d8237681a7396abfe7d161292636b8cce4 100644
--- a/arch/powerpc/include/asm/vdso/getrandom.h
+++ b/arch/powerpc/include/asm/vdso/getrandom.h
@@ -43,20 +43,21 @@ static __always_inline ssize_t getrandom_syscall(void *buffer, size_t len, unsig
(unsigned long)len, (unsigned long)flags);
}
-static __always_inline struct vdso_rng_data *__arch_get_vdso_rng_data(void)
+static __always_inline const struct vdso_rng_data *__ppc_get_vdso_u_rng_data(void)
{
- struct vdso_arch_data *data;
+ struct vdso_rng_data *data;
asm (
" bcl 20, 31, .+4 ;"
"0: mflr %0 ;"
- " addis %0, %0, (_vdso_datapage - 0b)@ha ;"
- " addi %0, %0, (_vdso_datapage - 0b)@l ;"
+ " addis %0, %0, (vdso_u_rng_data - 0b)@ha ;"
+ " addi %0, %0, (vdso_u_rng_data - 0b)@l ;"
: "=r" (data) : : "lr"
);
- return &data->rng_data;
+ return data;
}
+#define __arch_get_vdso_u_rng_data __ppc_get_vdso_u_rng_data
ssize_t __c_kernel_getrandom(void *buffer, size_t len, unsigned int flags, void *opaque_state,
size_t opaque_len);
diff --git a/arch/powerpc/include/asm/vdso/gettimeofday.h b/arch/powerpc/include/asm/vdso/gettimeofday.h
index c6390890a60c2fdcb608bf321b2945c3fb372f54..bddd9cde97db197d0d3daba6c2289cb29e6b5a75 100644
--- a/arch/powerpc/include/asm/vdso/gettimeofday.h
+++ b/arch/powerpc/include/asm/vdso/gettimeofday.h
@@ -94,22 +94,29 @@ int clock_getres32_fallback(clockid_t _clkid, struct old_timespec32 *_ts)
#endif
static __always_inline u64 __arch_get_hw_counter(s32 clock_mode,
- const struct vdso_data *vd)
+ const struct vdso_time_data *vd)
{
return get_tb();
}
-const struct vdso_data *__arch_get_vdso_data(void);
-
#ifdef CONFIG_TIME_NS
-static __always_inline
-const struct vdso_data *__arch_get_timens_vdso_data(const struct vdso_data *vd)
+static __always_inline const struct vdso_time_data *__ppc_get_vdso_u_timens_data(void)
{
- return (void *)vd + (1U << CONFIG_PAGE_SHIFT);
+ struct vdso_time_data *time_data;
+
+ asm(
+ " bcl 20, 31, .+4\n"
+ "0: mflr %0\n"
+ " addis %0, %0, (vdso_u_timens_data - 0b)@ha\n"
+ " addi %0, %0, (vdso_u_timens_data - 0b)@l\n"
+ : "=r" (time_data) :: "lr");
+
+ return time_data;
}
+#define __arch_get_vdso_u_timens_data __ppc_get_vdso_u_timens_data
#endif
-static inline bool vdso_clocksource_ok(const struct vdso_data *vd)
+static inline bool vdso_clocksource_ok(const struct vdso_time_data *vd)
{
return true;
}
@@ -135,21 +142,22 @@ static __always_inline u64 vdso_shift_ns(u64 ns, unsigned long shift)
#ifdef __powerpc64__
int __c_kernel_clock_gettime(clockid_t clock, struct __kernel_timespec *ts,
- const struct vdso_data *vd);
+ const struct vdso_time_data *vd);
int __c_kernel_clock_getres(clockid_t clock_id, struct __kernel_timespec *res,
- const struct vdso_data *vd);
+ const struct vdso_time_data *vd);
#else
int __c_kernel_clock_gettime(clockid_t clock, struct old_timespec32 *ts,
- const struct vdso_data *vd);
+ const struct vdso_time_data *vd);
int __c_kernel_clock_gettime64(clockid_t clock, struct __kernel_timespec *ts,
- const struct vdso_data *vd);
+ const struct vdso_time_data *vd);
int __c_kernel_clock_getres(clockid_t clock_id, struct old_timespec32 *res,
- const struct vdso_data *vd);
+ const struct vdso_time_data *vd);
#endif
int __c_kernel_gettimeofday(struct __kernel_old_timeval *tv, struct timezone *tz,
- const struct vdso_data *vd);
+ const struct vdso_time_data *vd);
__kernel_old_time_t __c_kernel_time(__kernel_old_time_t *time,
- const struct vdso_data *vd);
+ const struct vdso_time_data *vd);
+
#endif /* __ASSEMBLY__ */
#endif /* _ASM_POWERPC_VDSO_GETTIMEOFDAY_H */
diff --git a/arch/powerpc/include/asm/vdso/vsyscall.h b/arch/powerpc/include/asm/vdso/vsyscall.h
index 48560a11955956b8fbb59360334a81972723bd57..c2c9ae1b22e71a3f87e5a1a351699c7ab42b2f95 100644
--- a/arch/powerpc/include/asm/vdso/vsyscall.h
+++ b/arch/powerpc/include/asm/vdso/vsyscall.h
@@ -6,19 +6,6 @@
#include <asm/vdso_datapage.h>
-static __always_inline
-struct vdso_data *__arch_get_k_vdso_data(void)
-{
- return vdso_data->data;
-}
-#define __arch_get_k_vdso_data __arch_get_k_vdso_data
-
-static __always_inline
-struct vdso_rng_data *__arch_get_k_vdso_rng_data(void)
-{
- return &vdso_data->rng_data;
-}
-
/* The asm-generic header needs to be included after the definitions above */
#include <asm-generic/vdso/vsyscall.h>
diff --git a/arch/powerpc/include/asm/vdso_datapage.h b/arch/powerpc/include/asm/vdso_datapage.h
index a202f5b63479533a7f45a74df015feb59f3d7c87..95d45a50355d269454dd3e175a5b3844181536b5 100644
--- a/arch/powerpc/include/asm/vdso_datapage.h
+++ b/arch/powerpc/include/asm/vdso_datapage.h
@@ -11,56 +11,18 @@
#ifndef __ASSEMBLY__
-#include <linux/unistd.h>
-#include <linux/time.h>
#include <vdso/datapage.h>
-#define SYSCALL_MAP_SIZE ((NR_syscalls + 31) / 32)
-
-#ifdef CONFIG_PPC64
-
-struct vdso_arch_data {
- __u64 tb_ticks_per_sec; /* Timebase tics / sec */
- __u32 dcache_block_size; /* L1 d-cache block size */
- __u32 icache_block_size; /* L1 i-cache block size */
- __u32 dcache_log_block_size; /* L1 d-cache log block size */
- __u32 icache_log_block_size; /* L1 i-cache log block size */
- __u32 syscall_map[SYSCALL_MAP_SIZE]; /* Map of syscalls */
- __u32 compat_syscall_map[SYSCALL_MAP_SIZE]; /* Map of compat syscalls */
-
- struct vdso_rng_data rng_data;
-
- struct vdso_data data[CS_BASES] __aligned(1 << CONFIG_PAGE_SHIFT);
-};
-
-#else /* CONFIG_PPC64 */
-
-struct vdso_arch_data {
- __u64 tb_ticks_per_sec; /* Timebase tics / sec */
- __u32 syscall_map[SYSCALL_MAP_SIZE]; /* Map of syscalls */
- __u32 compat_syscall_map[0]; /* No compat syscalls on PPC32 */
- struct vdso_rng_data rng_data;
-
- struct vdso_data data[CS_BASES] __aligned(1 << CONFIG_PAGE_SHIFT);
-};
-
-#endif /* CONFIG_PPC64 */
-
-extern struct vdso_arch_data *vdso_data;
-
#else /* __ASSEMBLY__ */
-.macro get_datapage ptr offset=0
+.macro get_datapage ptr symbol
bcl 20, 31, .+4
999:
mflr \ptr
- addis \ptr, \ptr, (_vdso_datapage - 999b + \offset)@ha
- addi \ptr, \ptr, (_vdso_datapage - 999b + \offset)@l
+ addis \ptr, \ptr, (\symbol - 999b)@ha
+ addi \ptr, \ptr, (\symbol - 999b)@l
.endm
-#include <asm/asm-offsets.h>
-#include <asm/page.h>
-
#endif /* __ASSEMBLY__ */
#endif /* __KERNEL__ */
diff --git a/arch/powerpc/kernel/asm-offsets.c b/arch/powerpc/kernel/asm-offsets.c
index 7a390bd4f4af3c7408b3e3c5ef6d43b95b3b6463..b3048f6d3822c0c457f4aa2ccb5dc870495ba79b 100644
--- a/arch/powerpc/kernel/asm-offsets.c
+++ b/arch/powerpc/kernel/asm-offsets.c
@@ -334,7 +334,6 @@ int main(void)
#endif /* ! CONFIG_PPC64 */
/* datapage offsets for use by vdso */
- OFFSET(VDSO_DATA_OFFSET, vdso_arch_data, data);
OFFSET(CFG_TB_TICKS_PER_SEC, vdso_arch_data, tb_ticks_per_sec);
#ifdef CONFIG_PPC64
OFFSET(CFG_ICACHE_BLOCKSZ, vdso_arch_data, icache_block_size);
diff --git a/arch/powerpc/kernel/time.c b/arch/powerpc/kernel/time.c
index 0727332ad86fbcfcf8ca18b344ba04381e827c79..15784c5c95c77f1eccfa948a36ba69386a2c175b 100644
--- a/arch/powerpc/kernel/time.c
+++ b/arch/powerpc/kernel/time.c
@@ -950,7 +950,7 @@ void __init time_init(void)
sys_tz.tz_dsttime = 0;
}
- vdso_data->tb_ticks_per_sec = tb_ticks_per_sec;
+ vdso_k_arch_data->tb_ticks_per_sec = tb_ticks_per_sec;
#ifdef CONFIG_PPC64_PROC_SYSTEMCFG
systemcfg->tb_ticks_per_sec = tb_ticks_per_sec;
#endif
diff --git a/arch/powerpc/kernel/vdso.c b/arch/powerpc/kernel/vdso.c
index 43379365ce1b37cfba662ea58feca5e73dd5f700..219d67bcf747e79f48d09a50f5cb9624bcc0f7b1 100644
--- a/arch/powerpc/kernel/vdso.c
+++ b/arch/powerpc/kernel/vdso.c
@@ -17,7 +17,7 @@
#include <linux/elf.h>
#include <linux/security.h>
#include <linux/syscalls.h>
-#include <linux/time_namespace.h>
+#include <linux/vdso_datastore.h>
#include <vdso/datapage.h>
#include <asm/syscall.h>
@@ -32,6 +32,8 @@
#include <asm/vdso_datapage.h>
#include <asm/setup.h>
+static_assert(__VDSO_PAGES == VDSO_NR_PAGES);
+
/* The alignment of the vDSO */
#define VDSO_ALIGNMENT (1 << 16)
@@ -40,24 +42,6 @@ extern char vdso64_start, vdso64_end;
long sys_ni_syscall(void);
-/*
- * The vdso data page (aka. systemcfg for old ppc64 fans) is here.
- * Once the early boot kernel code no longer needs to muck around
- * with it, it will become dynamically allocated
- */
-static union {
- struct vdso_arch_data data;
- u8 page[2 * PAGE_SIZE];
-} vdso_data_store __page_aligned_data;
-struct vdso_arch_data *vdso_data = &vdso_data_store.data;
-
-enum vvar_pages {
- VVAR_BASE_PAGE_OFFSET,
- VVAR_TIME_PAGE_OFFSET,
- VVAR_TIMENS_PAGE_OFFSET,
- VVAR_NR_PAGES,
-};
-
static int vdso_mremap(const struct vm_special_mapping *sm, struct vm_area_struct *new_vma,
unsigned long text_size)
{
@@ -96,14 +80,6 @@ static void vdso_close(const struct vm_special_mapping *sm, struct vm_area_struc
mm->context.vdso = NULL;
}
-static vm_fault_t vvar_fault(const struct vm_special_mapping *sm,
- struct vm_area_struct *vma, struct vm_fault *vmf);
-
-static struct vm_special_mapping vvar_spec __ro_after_init = {
- .name = "[vvar]",
- .fault = vvar_fault,
-};
-
static struct vm_special_mapping vdso32_spec __ro_after_init = {
.name = "[vdso]",
.mremap = vdso32_mremap,
@@ -116,73 +92,6 @@ static struct vm_special_mapping vdso64_spec __ro_after_init = {
.close = vdso_close,
};
-#ifdef CONFIG_TIME_NS
-struct vdso_data *arch_get_vdso_data(void *vvar_page)
-{
- return vvar_page;
-}
-
-/*
- * The vvar mapping contains data for a specific time namespace, so when a task
- * changes namespace we must unmap its vvar data for the old namespace.
- * Subsequent faults will map in data for the new namespace.
- *
- * For more details see timens_setup_vdso_data().
- */
-int vdso_join_timens(struct task_struct *task, struct time_namespace *ns)
-{
- struct mm_struct *mm = task->mm;
- VMA_ITERATOR(vmi, mm, 0);
- struct vm_area_struct *vma;
-
- mmap_read_lock(mm);
- for_each_vma(vmi, vma) {
- if (vma_is_special_mapping(vma, &vvar_spec))
- zap_vma_pages(vma);
- }
- mmap_read_unlock(mm);
-
- return 0;
-}
-#endif
-
-static vm_fault_t vvar_fault(const struct vm_special_mapping *sm,
- struct vm_area_struct *vma, struct vm_fault *vmf)
-{
- struct page *timens_page = find_timens_vvar_page(vma);
- unsigned long pfn;
-
- switch (vmf->pgoff) {
- case VVAR_BASE_PAGE_OFFSET:
- pfn = virt_to_pfn(vdso_data);
- break;
- case VVAR_TIME_PAGE_OFFSET:
- if (timens_page)
- pfn = page_to_pfn(timens_page);
- else
- pfn = virt_to_pfn(vdso_data->data);
- break;
-#ifdef CONFIG_TIME_NS
- case VVAR_TIMENS_PAGE_OFFSET:
- /*
- * If a task belongs to a time namespace then a namespace
- * specific VVAR is mapped with the VVAR_DATA_PAGE_OFFSET and
- * the real VVAR page is mapped with the VVAR_TIMENS_PAGE_OFFSET
- * offset.
- * See also the comment near timens_setup_vdso_data().
- */
- if (!timens_page)
- return VM_FAULT_SIGBUS;
- pfn = virt_to_pfn(vdso_data->data);
- break;
-#endif /* CONFIG_TIME_NS */
- default:
- return VM_FAULT_SIGBUS;
- }
-
- return vmf_insert_pfn(vma, vmf->address, pfn);
-}
-
/*
* This is called from binfmt_elf, we create the special vma for the
* vDSO and insert it into the mm struct tree
@@ -191,7 +100,7 @@ static int __arch_setup_additional_pages(struct linux_binprm *bprm, int uses_int
{
unsigned long vdso_size, vdso_base, mappings_size;
struct vm_special_mapping *vdso_spec;
- unsigned long vvar_size = VVAR_NR_PAGES * PAGE_SIZE;
+ unsigned long vvar_size = VDSO_NR_PAGES * PAGE_SIZE;
struct mm_struct *mm = current->mm;
struct vm_area_struct *vma;
@@ -217,9 +126,7 @@ static int __arch_setup_additional_pages(struct linux_binprm *bprm, int uses_int
/* Add required alignment. */
vdso_base = ALIGN(vdso_base, VDSO_ALIGNMENT);
- vma = _install_special_mapping(mm, vdso_base, vvar_size,
- VM_READ | VM_MAYREAD | VM_IO |
- VM_DONTDUMP | VM_PFNMAP, &vvar_spec);
+ vma = vdso_install_vvar_mapping(mm, vdso_base);
if (IS_ERR(vma))
return PTR_ERR(vma);
@@ -299,10 +206,10 @@ static void __init vdso_setup_syscall_map(void)
for (i = 0; i < NR_syscalls; i++) {
if (sys_call_table[i] != (void *)&sys_ni_syscall)
- vdso_data->syscall_map[i >> 5] |= 0x80000000UL >> (i & 0x1f);
+ vdso_k_arch_data->syscall_map[i >> 5] |= 0x80000000UL >> (i & 0x1f);
if (IS_ENABLED(CONFIG_COMPAT) &&
compat_sys_call_table[i] != (void *)&sys_ni_syscall)
- vdso_data->compat_syscall_map[i >> 5] |= 0x80000000UL >> (i & 0x1f);
+ vdso_k_arch_data->compat_syscall_map[i >> 5] |= 0x80000000UL >> (i & 0x1f);
}
}
@@ -352,10 +259,10 @@ static struct page ** __init vdso_setup_pages(void *start, void *end)
static int __init vdso_init(void)
{
#ifdef CONFIG_PPC64
- vdso_data->dcache_block_size = ppc64_caches.l1d.block_size;
- vdso_data->icache_block_size = ppc64_caches.l1i.block_size;
- vdso_data->dcache_log_block_size = ppc64_caches.l1d.log_block_size;
- vdso_data->icache_log_block_size = ppc64_caches.l1i.log_block_size;
+ vdso_k_arch_data->dcache_block_size = ppc64_caches.l1d.block_size;
+ vdso_k_arch_data->icache_block_size = ppc64_caches.l1i.block_size;
+ vdso_k_arch_data->dcache_log_block_size = ppc64_caches.l1d.log_block_size;
+ vdso_k_arch_data->icache_log_block_size = ppc64_caches.l1i.log_block_size;
#endif /* CONFIG_PPC64 */
vdso_setup_syscall_map();
diff --git a/arch/powerpc/kernel/vdso/cacheflush.S b/arch/powerpc/kernel/vdso/cacheflush.S
index 0085ae464dac9c32381625a6969a4e422ad34eb7..488d3ade11e64996b30f42777251df8499eda92c 100644
--- a/arch/powerpc/kernel/vdso/cacheflush.S
+++ b/arch/powerpc/kernel/vdso/cacheflush.S
@@ -30,7 +30,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_COHERENT_ICACHE)
#ifdef CONFIG_PPC64
mflr r12
.cfi_register lr,r12
- get_datapage r10
+ get_datapage r10 vdso_u_arch_data
mtlr r12
.cfi_restore lr
#endif
diff --git a/arch/powerpc/kernel/vdso/datapage.S b/arch/powerpc/kernel/vdso/datapage.S
index db8e167f01667eb95b3dc74f6771e610411bba90..d23b2e8e2a34ca9b142231eb3a492716a49b2248 100644
--- a/arch/powerpc/kernel/vdso/datapage.S
+++ b/arch/powerpc/kernel/vdso/datapage.S
@@ -28,7 +28,7 @@ V_FUNCTION_BEGIN(__kernel_get_syscall_map)
mflr r12
.cfi_register lr,r12
mr. r4,r3
- get_datapage r3
+ get_datapage r3 vdso_u_arch_data
mtlr r12
#ifdef __powerpc64__
addi r3,r3,CFG_SYSCALL_MAP64
@@ -52,7 +52,7 @@ V_FUNCTION_BEGIN(__kernel_get_tbfreq)
.cfi_startproc
mflr r12
.cfi_register lr,r12
- get_datapage r3
+ get_datapage r3 vdso_u_arch_data
#ifndef __powerpc64__
lwz r4,(CFG_TB_TICKS_PER_SEC + 4)(r3)
#endif
diff --git a/arch/powerpc/kernel/vdso/gettimeofday.S b/arch/powerpc/kernel/vdso/gettimeofday.S
index 5333848322ca6105018d501952e3bf42475f49df..79c967212444732da50805fd086c6f2a3c75b0cc 100644
--- a/arch/powerpc/kernel/vdso/gettimeofday.S
+++ b/arch/powerpc/kernel/vdso/gettimeofday.S
@@ -33,9 +33,9 @@
.cfi_rel_offset r2, PPC_MIN_STKFRM + STK_GOT
#endif
.ifeq \call_time
- get_datapage r5 VDSO_DATA_OFFSET
+ get_datapage r5 vdso_u_time_data
.else
- get_datapage r4 VDSO_DATA_OFFSET
+ get_datapage r4 vdso_u_time_data
.endif
bl CFUNC(DOTSYM(\funct))
PPC_LL r0, PPC_MIN_STKFRM + PPC_LR_STKOFF(r1)
diff --git a/arch/powerpc/kernel/vdso/vdso32.lds.S b/arch/powerpc/kernel/vdso/vdso32.lds.S
index 1a1b0b6d681a9977e4ef8042e52d8d33da61887e..72a1012b8a205c6357cecb4b53d2d8e1ff59b051 100644
--- a/arch/powerpc/kernel/vdso/vdso32.lds.S
+++ b/arch/powerpc/kernel/vdso/vdso32.lds.S
@@ -6,6 +6,7 @@
#include <asm/vdso.h>
#include <asm/page.h>
#include <asm-generic/vmlinux.lds.h>
+#include <vdso/datapage.h>
#ifdef __LITTLE_ENDIAN__
OUTPUT_FORMAT("elf32-powerpcle", "elf32-powerpcle", "elf32-powerpcle")
@@ -16,7 +17,8 @@ OUTPUT_ARCH(powerpc:common)
SECTIONS
{
- PROVIDE(_vdso_datapage = . - 3 * PAGE_SIZE);
+ VDSO_VVAR_SYMS
+
. = SIZEOF_HEADERS;
.hash : { *(.hash) } :text
diff --git a/arch/powerpc/kernel/vdso/vdso64.lds.S b/arch/powerpc/kernel/vdso/vdso64.lds.S
index e21b5506cad62b16e677be74fda7921ec917141a..32102a05eaa7e015e0f89e4a94a3c5e31da7d460 100644
--- a/arch/powerpc/kernel/vdso/vdso64.lds.S
+++ b/arch/powerpc/kernel/vdso/vdso64.lds.S
@@ -6,6 +6,7 @@
#include <asm/vdso.h>
#include <asm/page.h>
#include <asm-generic/vmlinux.lds.h>
+#include <vdso/datapage.h>
#ifdef __LITTLE_ENDIAN__
OUTPUT_FORMAT("elf64-powerpcle", "elf64-powerpcle", "elf64-powerpcle")
@@ -16,7 +17,8 @@ OUTPUT_ARCH(powerpc:common64)
SECTIONS
{
- PROVIDE(_vdso_datapage = . - 3 * PAGE_SIZE);
+ VDSO_VVAR_SYMS
+
. = SIZEOF_HEADERS;
.hash : { *(.hash) } :text
diff --git a/arch/powerpc/kernel/vdso/vgettimeofday.c b/arch/powerpc/kernel/vdso/vgettimeofday.c
index 55a287c9a7366aa59ab4af1e760a8995f588a4d5..6f5167d81af5f3e6e755dbda4307769e45a28421 100644
--- a/arch/powerpc/kernel/vdso/vgettimeofday.c
+++ b/arch/powerpc/kernel/vdso/vgettimeofday.c
@@ -7,43 +7,43 @@
#ifdef __powerpc64__
int __c_kernel_clock_gettime(clockid_t clock, struct __kernel_timespec *ts,
- const struct vdso_data *vd)
+ const struct vdso_time_data *vd)
{
return __cvdso_clock_gettime_data(vd, clock, ts);
}
int __c_kernel_clock_getres(clockid_t clock_id, struct __kernel_timespec *res,
- const struct vdso_data *vd)
+ const struct vdso_time_data *vd)
{
return __cvdso_clock_getres_data(vd, clock_id, res);
}
#else
int __c_kernel_clock_gettime(clockid_t clock, struct old_timespec32 *ts,
- const struct vdso_data *vd)
+ const struct vdso_time_data *vd)
{
return __cvdso_clock_gettime32_data(vd, clock, ts);
}
int __c_kernel_clock_gettime64(clockid_t clock, struct __kernel_timespec *ts,
- const struct vdso_data *vd)
+ const struct vdso_time_data *vd)
{
return __cvdso_clock_gettime_data(vd, clock, ts);
}
int __c_kernel_clock_getres(clockid_t clock_id, struct old_timespec32 *res,
- const struct vdso_data *vd)
+ const struct vdso_time_data *vd)
{
return __cvdso_clock_getres_time32_data(vd, clock_id, res);
}
#endif
int __c_kernel_gettimeofday(struct __kernel_old_timeval *tv, struct timezone *tz,
- const struct vdso_data *vd)
+ const struct vdso_time_data *vd)
{
return __cvdso_gettimeofday_data(vd, tv, tz);
}
-__kernel_old_time_t __c_kernel_time(__kernel_old_time_t *time, const struct vdso_data *vd)
+__kernel_old_time_t __c_kernel_time(__kernel_old_time_t *time, const struct vdso_time_data *vd)
{
return __cvdso_time_data(vd, time);
}
--
2.47.1
^ permalink raw reply related [flat|nested] 29+ messages in thread* Re: [PATCH 12/17] powerpc/vdso: Switch to generic storage implementation
2024-12-16 14:10 ` [PATCH 12/17] powerpc/vdso: " Thomas Weißschuh
@ 2024-12-18 7:20 ` Christophe Leroy
2024-12-18 10:16 ` Thomas Weißschuh
2024-12-18 10:20 ` Christophe Leroy
0 siblings, 2 replies; 29+ messages in thread
From: Christophe Leroy @ 2024-12-18 7:20 UTC (permalink / raw)
To: Thomas Weißschuh, James E.J. Bottomley, Helge Deller,
Andy Lutomirski, Thomas Gleixner, Vincenzo Frascino,
Anna-Maria Behnsen, Frederic Weisbecker, Andrew Morton,
Catalin Marinas, Will Deacon, Theodore Ts'o,
Jason A. Donenfeld, Paul Walmsley, Palmer Dabbelt, Albert Ou,
Huacai Chen, WANG Xuerui, Russell King, Heiko Carstens,
Vasily Gorbik, Alexander Gordeev, Christian Borntraeger,
Sven Schnelle, Thomas Bogendoerfer, Michael Ellerman,
Nicholas Piggin, Naveen N Rao, Madhavan Srinivasan, Ingo Molnar,
Borislav Petkov, Dave Hansen, x86, H. Peter Anvin, Arnd Bergmann
Cc: linux-parisc, linux-kernel, linux-arm-kernel, linux-riscv,
loongarch, linux-s390, linux-mips, linuxppc-dev, linux-arch,
Nam Cao
Le 16/12/2024 à 15:10, Thomas Weißschuh a écrit :
> The generic storage implementation provides the same features as the
> custom one. However it can be shared between architectures, making
> maintenance easier.
>
> Co-developed-by: Nam Cao <namcao@linutronix.de>
> Signed-off-by: Nam Cao <namcao@linutronix.de>
> Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
> ---
> arch/powerpc/Kconfig | 2 +
> arch/powerpc/include/asm/vdso.h | 1 +
> arch/powerpc/include/asm/vdso/arch_data.h | 37 +++++++++
> arch/powerpc/include/asm/vdso/getrandom.h | 11 +--
> arch/powerpc/include/asm/vdso/gettimeofday.h | 36 +++++----
> arch/powerpc/include/asm/vdso/vsyscall.h | 13 ---
> arch/powerpc/include/asm/vdso_datapage.h | 44 +---------
> arch/powerpc/kernel/asm-offsets.c | 1 -
> arch/powerpc/kernel/time.c | 2 +-
> arch/powerpc/kernel/vdso.c | 115 +++------------------------
> arch/powerpc/kernel/vdso/cacheflush.S | 2 +-
> arch/powerpc/kernel/vdso/datapage.S | 4 +-
> arch/powerpc/kernel/vdso/gettimeofday.S | 4 +-
> arch/powerpc/kernel/vdso/vdso32.lds.S | 4 +-
> arch/powerpc/kernel/vdso/vdso64.lds.S | 4 +-
> arch/powerpc/kernel/vdso/vgettimeofday.c | 14 ++--
> 16 files changed, 101 insertions(+), 193 deletions(-)
>
> diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
> index a0ce777f97063bf858942c60654d8411bcf2a3dc..600fa3b917ee902d016f2a04376950a9dc49074f 100644
> --- a/arch/powerpc/Kconfig
> +++ b/arch/powerpc/Kconfig
> @@ -156,6 +156,7 @@ config PPC
> select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
> select ARCH_HAS_UACCESS_FLUSHCACHE
> select ARCH_HAS_UBSAN
> + select ARCH_HAS_VDSO_ARCH_DATA
> select ARCH_HAVE_NMI_SAFE_CMPXCHG
> select ARCH_HAVE_EXTRA_ELF_NOTES if SPU_BASE
> select ARCH_KEEP_MEMBLOCK
> @@ -206,6 +207,7 @@ config PPC
> select GENERIC_PTDUMP
> select GENERIC_SMP_IDLE_THREAD
> select GENERIC_TIME_VSYSCALL
> + select GENERIC_VDSO_DATA_STORE
> select GENERIC_VDSO_TIME_NS
> select HAS_IOPORT if PCI
> select HAVE_ARCH_AUDITSYSCALL
> diff --git a/arch/powerpc/include/asm/vdso.h b/arch/powerpc/include/asm/vdso.h
> index 8d972bc98b55fe916f23488ca9e2a5918046b9aa..1ca23fbfe087ae90b90c4286335f86d9f8121078 100644
> --- a/arch/powerpc/include/asm/vdso.h
> +++ b/arch/powerpc/include/asm/vdso.h
> @@ -3,6 +3,7 @@
> #define _ASM_POWERPC_VDSO_H
>
> #define VDSO_VERSION_STRING LINUX_2.6.15
> +#define __VDSO_PAGES 4
>
> #ifndef __ASSEMBLY__
>
> diff --git a/arch/powerpc/include/asm/vdso/arch_data.h b/arch/powerpc/include/asm/vdso/arch_data.h
> new file mode 100644
> index 0000000000000000000000000000000000000000..c240a6b875181ac4159f2e80b11f9bf214e22808
> --- /dev/null
> +++ b/arch/powerpc/include/asm/vdso/arch_data.h
> @@ -0,0 +1,37 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +/*
> + * Copyright (C) 2002 Peter Bergner <bergner@vnet.ibm.com>, IBM
> + * Copyright (C) 2005 Benjamin Herrenschmidy <benh@kernel.crashing.org>,
> + * IBM Corp.
> + */
> +#ifndef _ASM_POWERPC_VDSO_ARCH_DATA_H
> +#define _ASM_POWERPC_VDSO_ARCH_DATA_H
> +
> +#include <linux/unistd.h>
> +#include <linux/types.h>
> +
> +#define SYSCALL_MAP_SIZE ((NR_syscalls + 31) / 32)
> +
> +#ifdef CONFIG_PPC64
> +
> +struct vdso_arch_data {
> + __u64 tb_ticks_per_sec; /* Timebase tics / sec */
> + __u32 dcache_block_size; /* L1 d-cache block size */
> + __u32 icache_block_size; /* L1 i-cache block size */
> + __u32 dcache_log_block_size; /* L1 d-cache log block size */
> + __u32 icache_log_block_size; /* L1 i-cache log block size */
> + __u32 syscall_map[SYSCALL_MAP_SIZE]; /* Map of syscalls */
> + __u32 compat_syscall_map[SYSCALL_MAP_SIZE]; /* Map of compat syscalls */
> +};
> +
> +#else /* CONFIG_PPC64 */
> +
> +struct vdso_arch_data {
> + __u64 tb_ticks_per_sec; /* Timebase tics / sec */
> + __u32 syscall_map[SYSCALL_MAP_SIZE]; /* Map of syscalls */
> + __u32 compat_syscall_map[0]; /* No compat syscalls on PPC32 */
> +};
> +
> +#endif /* CONFIG_PPC64 */
> +
> +#endif /* _ASM_POWERPC_VDSO_ARCH_DATA_H */
> diff --git a/arch/powerpc/include/asm/vdso/getrandom.h b/arch/powerpc/include/asm/vdso/getrandom.h
> index 80ce0709725eb89c1f3b69e0733038b458fbf24f..c82eb0d8237681a7396abfe7d161292636b8cce4 100644
> --- a/arch/powerpc/include/asm/vdso/getrandom.h
> +++ b/arch/powerpc/include/asm/vdso/getrandom.h
> @@ -43,20 +43,21 @@ static __always_inline ssize_t getrandom_syscall(void *buffer, size_t len, unsig
> (unsigned long)len, (unsigned long)flags);
> }
>
> -static __always_inline struct vdso_rng_data *__arch_get_vdso_rng_data(void)
> +static __always_inline const struct vdso_rng_data *__ppc_get_vdso_u_rng_data(void)
> {
> - struct vdso_arch_data *data;
> + struct vdso_rng_data *data;
>
> asm (
> " bcl 20, 31, .+4 ;"
> "0: mflr %0 ;"
> - " addis %0, %0, (_vdso_datapage - 0b)@ha ;"
> - " addi %0, %0, (_vdso_datapage - 0b)@l ;"
> + " addis %0, %0, (vdso_u_rng_data - 0b)@ha ;"
> + " addi %0, %0, (vdso_u_rng_data - 0b)@l ;"
> : "=r" (data) : : "lr"
> );
>
> - return &data->rng_data;
> + return data;
> }
> +#define __arch_get_vdso_u_rng_data __ppc_get_vdso_u_rng_data
>
> ssize_t __c_kernel_getrandom(void *buffer, size_t len, unsigned int flags, void *opaque_state,
> size_t opaque_len);
> diff --git a/arch/powerpc/include/asm/vdso/gettimeofday.h b/arch/powerpc/include/asm/vdso/gettimeofday.h
> index c6390890a60c2fdcb608bf321b2945c3fb372f54..bddd9cde97db197d0d3daba6c2289cb29e6b5a75 100644
> --- a/arch/powerpc/include/asm/vdso/gettimeofday.h
> +++ b/arch/powerpc/include/asm/vdso/gettimeofday.h
> @@ -94,22 +94,29 @@ int clock_getres32_fallback(clockid_t _clkid, struct old_timespec32 *_ts)
> #endif
>
> static __always_inline u64 __arch_get_hw_counter(s32 clock_mode,
> - const struct vdso_data *vd)
> + const struct vdso_time_data *vd)
> {
> return get_tb();
> }
>
> -const struct vdso_data *__arch_get_vdso_data(void);
> -
> #ifdef CONFIG_TIME_NS
> -static __always_inline
> -const struct vdso_data *__arch_get_timens_vdso_data(const struct vdso_data *vd)
> +static __always_inline const struct vdso_time_data *__ppc_get_vdso_u_timens_data(void)
> {
> - return (void *)vd + (1U << CONFIG_PAGE_SHIFT);
> + struct vdso_time_data *time_data;
> +
> + asm(
> + " bcl 20, 31, .+4\n"
> + "0: mflr %0\n"
> + " addis %0, %0, (vdso_u_timens_data - 0b)@ha\n"
> + " addi %0, %0, (vdso_u_timens_data - 0b)@l\n"
> + : "=r" (time_data) :: "lr");
> +
> + return time_data;
Please don't do that, it kills optimisation efforts done when
implementing VDSO time. Commit ce7d8056e38b ("powerpc/vdso: Prepare for
switching VDSO to generic C implementation.") explains why.
For time data, the bcl/mflr dance is done by get_datapage macro called
by cvdso_call macro in gettimeofday.S, and given to
__cvdso_clock_gettime_data() by __c_kernel_clock_gettime() in
vgettimeofday.c . Use that information and don't redo the bcl/mflr sequence.
See for instance function __c_kernel_clock_getres():
Before your series it is 30 instructions.
After your series it is 59 instructions.
Before:
000010f8 <__c_kernel_clock_getres>:
10f8: 28 03 00 0f cmplwi r3,15
10fc: 41 81 00 60 bgt 115c <__c_kernel_clock_getres+0x64>
1100: 81 45 00 04 lwz r10,4(r5)
1104: 3d 20 7f ff lis r9,32767
1108: 61 29 ff ff ori r9,r9,65535
110c: 7c 0a 48 00 cmpw r10,r9
1110: 40 a2 00 08 bne 1118 <__c_kernel_clock_getres+0x20>
1114: 38 a5 40 00 addi r5,r5,16384
1118: 39 20 00 01 li r9,1
111c: 7d 29 18 30 slw r9,r9,r3
1120: 71 2a 08 93 andi. r10,r9,2195
1124: 40 82 00 30 bne 1154 <__c_kernel_clock_getres+0x5c>
1128: 71 29 00 60 andi. r9,r9,96
112c: 41 82 00 30 beq 115c <__c_kernel_clock_getres+0x64>
1130: 3d 20 00 98 lis r9,152
1134: 61 29 96 80 ori r9,r9,38528
1138: 2c 04 00 00 cmpwi r4,0
113c: 41 82 00 10 beq 114c <__c_kernel_clock_getres+0x54>
1140: 39 40 00 00 li r10,0
1144: 91 24 00 04 stw r9,4(r4)
1148: 91 44 00 00 stw r10,0(r4)
114c: 38 60 00 00 li r3,0
1150: 4e 80 00 20 blr
1154: 81 25 00 e8 lwz r9,232(r5)
1158: 4b ff ff e0 b 1138 <__c_kernel_clock_getres+0x40>
115c: 38 00 00 f7 li r0,247
1160: 44 00 00 02 sc
1164: 40 a3 00 08 bns 116c <__c_kernel_clock_getres+0x74>
1168: 7c 63 00 d0 neg r3,r3
116c: 4e 80 00 20 blr
After:
000011ac <__c_kernel_clock_getres>:
11ac: 28 03 00 0f cmplwi r3,15
11b0: 41 81 00 c0 bgt 1270 <__c_kernel_clock_getres+0xc4>
11b4: 81 45 00 04 lwz r10,4(r5)
11b8: 3d 20 7f ff lis r9,32767
11bc: 61 29 ff ff ori r9,r9,65535
11c0: 7c 0a 48 00 cmpw r10,r9
11c4: 41 82 00 48 beq 120c <__c_kernel_clock_getres+0x60>
11c8: 39 20 00 01 li r9,1
11cc: 7d 29 18 30 slw r9,r9,r3
11d0: 71 2a 08 93 andi. r10,r9,2195
11d4: 40 82 00 30 bne 1204 <__c_kernel_clock_getres+0x58>
11d8: 71 29 00 60 andi. r9,r9,96
11dc: 41 82 00 94 beq 1270 <__c_kernel_clock_getres+0xc4>
11e0: 3d 20 00 98 lis r9,152
11e4: 61 29 96 80 ori r9,r9,38528
11e8: 2c 04 00 00 cmpwi r4,0
11ec: 41 82 00 10 beq 11fc <__c_kernel_clock_getres+0x50>
11f0: 39 40 00 00 li r10,0
11f4: 91 24 00 04 stw r9,4(r4)
11f8: 91 44 00 00 stw r10,0(r4)
11fc: 38 60 00 00 li r3,0
1200: 4e 80 00 20 blr
1204: 81 25 00 e8 lwz r9,232(r5)
1208: 4b ff ff e0 b 11e8 <__c_kernel_clock_getres+0x3c>
120c: 39 20 00 01 li r9,1
1210: 7d 29 18 30 slw r9,r9,r3
1214: 71 2a 08 93 andi. r10,r9,2195
1218: 7c 08 02 a6 mflr r0
121c: 90 01 00 04 stw r0,4(r1)
1220: 42 9f 00 05 bcl 20,4*cr7+so,1224
<__c_kernel_clock_getres+0x78>
1224: 7c a8 02 a6 mflr r5
1228: 3c a5 ff ff addis r5,r5,-1
122c: 38 a5 2d dc addi r5,r5,11740
1230: 40 82 00 38 bne 1268 <__c_kernel_clock_getres+0xbc>
1234: 71 29 00 60 andi. r9,r9,96
1238: 41 82 00 4c beq 1284 <__c_kernel_clock_getres+0xd8>
123c: 3d 20 00 98 lis r9,152
1240: 61 29 96 80 ori r9,r9,38528
1244: 2c 04 00 00 cmpwi r4,0
1248: 41 82 00 10 beq 1258 <__c_kernel_clock_getres+0xac>
124c: 39 40 00 00 li r10,0
1250: 91 24 00 04 stw r9,4(r4)
1254: 91 44 00 00 stw r10,0(r4)
1258: 38 60 00 00 li r3,0
125c: 80 01 00 04 lwz r0,4(r1)
1260: 7c 08 03 a6 mtlr r0
1264: 4e 80 00 20 blr
1268: 81 25 00 e8 lwz r9,232(r5)
126c: 4b ff ff d8 b 1244 <__c_kernel_clock_getres+0x98>
1270: 38 00 00 f7 li r0,247
1274: 44 00 00 02 sc
1278: 40 a3 00 08 bns 1280 <__c_kernel_clock_getres+0xd4>
127c: 7c 63 00 d0 neg r3,r3
1280: 4e 80 00 20 blr
1284: 38 00 00 f7 li r0,247
1288: 44 00 00 02 sc
128c: 40 a3 00 08 bns 1294 <__c_kernel_clock_getres+0xe8>
1290: 7c 63 00 d0 neg r3,r3
1294: 4b ff ff c8 b 125c <__c_kernel_clock_getres+0xb0>
> }
> +#define __arch_get_vdso_u_timens_data __ppc_get_vdso_u_timens_data
There is not #ifdef __arch_get_vdso_u_timens_data anywhere, this #define
is not needed, the function should be called
__arch_get_vdso_u_timens_data() directly as before, unnecessary
indirections reduce readability.
> #endif
>
> -static inline bool vdso_clocksource_ok(const struct vdso_data *vd)
> +static inline bool vdso_clocksource_ok(const struct vdso_time_data *vd)
> {
> return true;
> }
^ permalink raw reply [flat|nested] 29+ messages in thread* Re: [PATCH 12/17] powerpc/vdso: Switch to generic storage implementation
2024-12-18 7:20 ` Christophe Leroy
@ 2024-12-18 10:16 ` Thomas Weißschuh
2024-12-18 10:20 ` Christophe Leroy
1 sibling, 0 replies; 29+ messages in thread
From: Thomas Weißschuh @ 2024-12-18 10:16 UTC (permalink / raw)
To: Christophe Leroy
Cc: James E.J. Bottomley, Helge Deller, Andy Lutomirski,
Thomas Gleixner, Vincenzo Frascino, Anna-Maria Behnsen,
Frederic Weisbecker, Andrew Morton, Catalin Marinas, Will Deacon,
Theodore Ts'o, Jason A. Donenfeld, Paul Walmsley,
Palmer Dabbelt, Albert Ou, Huacai Chen, WANG Xuerui, Russell King,
Heiko Carstens, Vasily Gorbik, Alexander Gordeev,
Christian Borntraeger, Sven Schnelle, Thomas Bogendoerfer,
Michael Ellerman, Nicholas Piggin, Naveen N Rao,
Madhavan Srinivasan, Ingo Molnar, Borislav Petkov, Dave Hansen,
x86, H. Peter Anvin, Arnd Bergmann, linux-parisc, linux-kernel,
linux-arm-kernel, linux-riscv, loongarch, linux-s390, linux-mips,
linuxppc-dev, linux-arch, Nam Cao
Hi Christophe,
On Wed, Dec 18, 2024 at 08:20:51AM +0100, Christophe Leroy wrote:
> Le 16/12/2024 à 15:10, Thomas Weißschuh a écrit :
[..]
> > #ifdef CONFIG_TIME_NS
> > -static __always_inline
> > -const struct vdso_data *__arch_get_timens_vdso_data(const struct vdso_data *vd)
> > +static __always_inline const struct vdso_time_data *__ppc_get_vdso_u_timens_data(void)
> > {
> > - return (void *)vd + (1U << CONFIG_PAGE_SHIFT);
> > + struct vdso_time_data *time_data;
> > +
> > + asm(
> > + " bcl 20, 31, .+4\n"
> > + "0: mflr %0\n"
> > + " addis %0, %0, (vdso_u_timens_data - 0b)@ha\n"
> > + " addi %0, %0, (vdso_u_timens_data - 0b)@l\n"
> > + : "=r" (time_data) :: "lr");
> > +
> > + return time_data;
>
> Please don't do that, it kills optimisation efforts done when implementing
> VDSO time. Commit ce7d8056e38b ("powerpc/vdso: Prepare for switching VDSO to
> generic C implementation.") explains why.
>
> For time data, the bcl/mflr dance is done by get_datapage macro called by
> cvdso_call macro in gettimeofday.S, and given to
> __cvdso_clock_gettime_data() by __c_kernel_clock_gettime() in
> vgettimeofday.c . Use that information and don't redo the bcl/mflr sequence.
So instead keeping the logic of this:
static __always_inline
const struct vdso_data *__arch_get_timens_vdso_data(const struct vdso_data *vd)
{
return (void *)vd + (1U << CONFIG_PAGE_SHIFT);
}
Makes sense.
Adding a constant value should be cheaper or just as cheap as a
PC-relative addressing for all architectures, so it can go into the
generic code, too.
[..]
> > }
> > +#define __arch_get_vdso_u_timens_data __ppc_get_vdso_u_timens_data
>
> There is not #ifdef __arch_get_vdso_u_timens_data anywhere, this #define is
> not needed, the function should be called __arch_get_vdso_u_timens_data()
> directly as before, unnecessary indirections reduce readability.
I'll see how this works out with the include order and conflicts with
symbols in include/vdso/datapage.h.
> > #endif
> > -static inline bool vdso_clocksource_ok(const struct vdso_data *vd)
> > +static inline bool vdso_clocksource_ok(const struct vdso_time_data *vd)
> > {
> > return true;
> > }
Thanks!
Thomas
^ permalink raw reply [flat|nested] 29+ messages in thread* Re: [PATCH 12/17] powerpc/vdso: Switch to generic storage implementation
2024-12-18 7:20 ` Christophe Leroy
2024-12-18 10:16 ` Thomas Weißschuh
@ 2024-12-18 10:20 ` Christophe Leroy
1 sibling, 0 replies; 29+ messages in thread
From: Christophe Leroy @ 2024-12-18 10:20 UTC (permalink / raw)
To: Thomas Weißschuh, James E.J. Bottomley, Helge Deller,
Andy Lutomirski, Thomas Gleixner, Vincenzo Frascino,
Anna-Maria Behnsen, Frederic Weisbecker, Andrew Morton,
Catalin Marinas, Will Deacon, Theodore Ts'o,
Jason A. Donenfeld, Paul Walmsley, Palmer Dabbelt, Albert Ou,
Huacai Chen, WANG Xuerui, Russell King, Heiko Carstens,
Vasily Gorbik, Alexander Gordeev, Christian Borntraeger,
Sven Schnelle, Thomas Bogendoerfer, Michael Ellerman,
Nicholas Piggin, Naveen N Rao, Madhavan Srinivasan, Ingo Molnar,
Borislav Petkov, Dave Hansen, x86, H. Peter Anvin, Arnd Bergmann
Cc: linux-parisc, linux-kernel, linux-arm-kernel, linux-riscv,
loongarch, linux-s390, linux-mips, linuxppc-dev, linux-arch,
Nam Cao
>> #ifdef CONFIG_TIME_NS
>> -static __always_inline
>> -const struct vdso_data *__arch_get_timens_vdso_data(const struct
>> vdso_data *vd)
>> +static __always_inline const struct vdso_time_data
>> *__ppc_get_vdso_u_timens_data(void)
>> {
>> - return (void *)vd + (1U << CONFIG_PAGE_SHIFT);
>> + struct vdso_time_data *time_data;
>> +
>> + asm(
>> + " bcl 20, 31, .+4\n"
>> + "0: mflr %0\n"
>> + " addis %0, %0, (vdso_u_timens_data - 0b)@ha\n"
>> + " addi %0, %0, (vdso_u_timens_data - 0b)@l\n"
>> + : "=r" (time_data) :: "lr");
>> +
>> + return time_data;
>
> Please don't do that, it kills optimisation efforts done when
> implementing VDSO time. Commit ce7d8056e38b ("powerpc/vdso: Prepare for
> switching VDSO to generic C implementation.") explains why.
>
> For time data, the bcl/mflr dance is done by get_datapage macro called
> by cvdso_call macro in gettimeofday.S, and given to
> __cvdso_clock_gettime_data() by __c_kernel_clock_gettime() in
> vgettimeofday.c . Use that information and don't redo the bcl/mflr
> sequence.
>
> See for instance function __c_kernel_clock_getres():
>
> Before your series it is 30 instructions.
> After your series it is 59 instructions.
>
It is even more obvious with __c_kernel_time()
Before your series it has 12 instructions,
After your series it has 26 instructions.
Before
00001408 <__c_kernel_time>:
1408: 81 44 00 04 lwz r10,4(r4)
140c: 6d 49 80 00 xoris r9,r10,32768
1410: 2c 09 ff ff cmpwi r9,-1
1414: 40 82 00 08 bne 141c <__c_kernel_time+0x14>
1418: 38 84 40 00 addi r4,r4,16384
141c: 2c 03 00 00 cmpwi r3,0
1420: 81 44 00 20 lwz r10,32(r4)
1424: 81 64 00 24 lwz r11,36(r4)
1428: 41 82 00 08 beq 1430 <__c_kernel_time+0x28>
142c: 91 63 00 00 stw r11,0(r3)
1430: 7d 63 5b 78 mr r3,r11
1434: 4e 80 00 20 blr
Versus after
00001534 <__c_kernel_time>:
1534: 81 44 00 04 lwz r10,4(r4)
1538: 6d 49 80 00 xoris r9,r10,32768
153c: 2c 09 ff ff cmpwi r9,-1
1540: 41 82 00 20 beq 1560 <__c_kernel_time+0x2c>
1544: 2c 03 00 00 cmpwi r3,0
1548: 81 44 00 20 lwz r10,32(r4)
154c: 81 64 00 24 lwz r11,36(r4)
1550: 41 82 00 08 beq 1558 <__c_kernel_time+0x24>
1554: 91 63 00 00 stw r11,0(r3)
1558: 7d 63 5b 78 mr r3,r11
155c: 4e 80 00 20 blr
1560: 7c 08 02 a6 mflr r0
1564: 2c 03 00 00 cmpwi r3,0
1568: 90 01 00 04 stw r0,4(r1)
156c: 42 9f 00 05 bcl 20,4*cr7+so,1570 <__c_kernel_time+0x3c>
1570: 7c 88 02 a6 mflr r4
1574: 3c 84 ff ff addis r4,r4,-1
1578: 38 84 2a 90 addi r4,r4,10896
157c: 81 44 00 20 lwz r10,32(r4)
1580: 81 64 00 24 lwz r11,36(r4)
1584: 41 82 00 08 beq 158c <__c_kernel_time+0x58>
1588: 91 63 00 00 stw r11,0(r3)
158c: 80 01 00 04 lwz r0,4(r1)
1590: 7d 63 5b 78 mr r3,r11
1594: 7c 08 03 a6 mtlr r0
1598: 4e 80 00 20 blr
Christophe
^ permalink raw reply [flat|nested] 29+ messages in thread
* [PATCH 13/17] x86/vdso: Switch to generic storage implementation
2024-12-16 14:09 [PATCH 00/17] vDSO: Introduce generic data storage Thomas Weißschuh
` (11 preceding siblings ...)
2024-12-16 14:10 ` [PATCH 12/17] powerpc/vdso: " Thomas Weißschuh
@ 2024-12-16 14:10 ` Thomas Weißschuh
2024-12-16 14:10 ` [PATCH 14/17] x86/vdso/vdso2c: Remove page handling Thomas Weißschuh
` (3 subsequent siblings)
16 siblings, 0 replies; 29+ messages in thread
From: Thomas Weißschuh @ 2024-12-16 14:10 UTC (permalink / raw)
To: James E.J. Bottomley, Helge Deller, Andy Lutomirski,
Thomas Gleixner, Vincenzo Frascino, Anna-Maria Behnsen,
Frederic Weisbecker, Andrew Morton, Catalin Marinas, Will Deacon,
Theodore Ts'o, Jason A. Donenfeld, Paul Walmsley,
Palmer Dabbelt, Albert Ou, Huacai Chen, WANG Xuerui, Russell King,
Heiko Carstens, Vasily Gorbik, Alexander Gordeev,
Christian Borntraeger, Sven Schnelle, Thomas Bogendoerfer,
Michael Ellerman, Nicholas Piggin, Christophe Leroy, Naveen N Rao,
Madhavan Srinivasan, Ingo Molnar, Borislav Petkov, Dave Hansen,
x86, H. Peter Anvin, Arnd Bergmann
Cc: linux-parisc, linux-kernel, linux-arm-kernel, linux-riscv,
loongarch, linux-s390, linux-mips, linuxppc-dev, linux-arch,
Nam Cao, Thomas Weißschuh
The generic storage implementation provides the same features as the
custom one. However it can be shared between architectures, making
maintenance easier.
This switch also moves the random state data out of the time data page.
The currently used hardcoded __VDSO_RND_DATA_OFFSET does not take into
account changes to the time data page layout.
Co-developed-by: Nam Cao <namcao@linutronix.de>
Signed-off-by: Nam Cao <namcao@linutronix.de>
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
---
arch/x86/Kconfig | 1 +
arch/x86/entry/vdso/vdso-layout.lds.S | 14 ++--
arch/x86/entry/vdso/vma.c | 125 ++-----------------------------
arch/x86/include/asm/vdso/getrandom.h | 10 ---
arch/x86/include/asm/vdso/gettimeofday.h | 25 +------
arch/x86/include/asm/vdso/vsyscall.h | 22 +-----
6 files changed, 19 insertions(+), 178 deletions(-)
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 9d7bd0ae48c4260f4abb6dbedc696e3915c230ea..e3d7f17dc414ca93d6e746dbc7f02afd2bc043a8 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -177,6 +177,7 @@ config X86
select GENERIC_SMP_IDLE_THREAD
select GENERIC_TIME_VSYSCALL
select GENERIC_GETTIMEOFDAY
+ select GENERIC_VDSO_DATA_STORE
select GENERIC_VDSO_TIME_NS
select GENERIC_VDSO_OVERFLOW_PROTECT
select GUP_GET_PXX_LOW_HIGH if X86_PAE
diff --git a/arch/x86/entry/vdso/vdso-layout.lds.S b/arch/x86/entry/vdso/vdso-layout.lds.S
index 872947c1004c35c006f7508eac7dff251c286aeb..6a628ead49beb3480dc750786c31dc125dfd017a 100644
--- a/arch/x86/entry/vdso/vdso-layout.lds.S
+++ b/arch/x86/entry/vdso/vdso-layout.lds.S
@@ -1,6 +1,7 @@
/* SPDX-License-Identifier: GPL-2.0 */
#include <asm/vdso.h>
#include <asm/vdso/vsyscall.h>
+#include <vdso/datapage.h>
/*
* Linker script for vDSO. This is an ELF shared object prelinked to
@@ -17,17 +18,16 @@ SECTIONS
* segment.
*/
- vvar_start = . - __VVAR_PAGES * PAGE_SIZE;
- vvar_page = vvar_start;
+ VDSO_VVAR_SYMS
- vdso_rng_data = vvar_page + __VDSO_RND_DATA_OFFSET;
-
- timens_page = vvar_start + PAGE_SIZE;
-
- vclock_pages = vvar_start + VDSO_NR_VCLOCK_PAGES * PAGE_SIZE;
+ vclock_pages = vdso_u_data + VDSO_NR_VCLOCK_PAGES * PAGE_SIZE;
pvclock_page = vclock_pages + VDSO_PAGE_PVCLOCK_OFFSET * PAGE_SIZE;
hvclock_page = vclock_pages + VDSO_PAGE_HVCLOCK_OFFSET * PAGE_SIZE;
+ /* For compatibility with vdso2c */
+ vvar_page = vdso_u_data;
+ vvar_start = vdso_u_data;
+
. = SIZEOF_HEADERS;
.hash : { *(.hash) } :text
diff --git a/arch/x86/entry/vdso/vma.c b/arch/x86/entry/vdso/vma.c
index 39e6efc1a9cab760b8a65e4b02c624e8c75244b5..b9872df56402f5d00a3134481df8f98b35ddbacb 100644
--- a/arch/x86/entry/vdso/vma.c
+++ b/arch/x86/entry/vdso/vma.c
@@ -14,7 +14,7 @@
#include <linux/elf.h>
#include <linux/cpu.h>
#include <linux/ptrace.h>
-#include <linux/time_namespace.h>
+#include <linux/vdso_datastore.h>
#include <asm/pvclock.h>
#include <asm/vgtod.h>
@@ -27,13 +27,7 @@
#include <asm/vdso/vsyscall.h>
#include <clocksource/hyperv_timer.h>
-struct vdso_data *arch_get_vdso_data(void *vvar_page)
-{
- return (struct vdso_data *)vvar_page;
-}
-
-static union vdso_data_store vdso_data_store __page_aligned_data;
-struct vdso_data *vdso_data = vdso_data_store.data;
+static_assert(VDSO_NR_PAGES + VDSO_NR_VCLOCK_PAGES == __VDSO_PAGES);
unsigned int vclocks_used __read_mostly;
@@ -54,7 +48,6 @@ int __init init_vdso_image(const struct vdso_image *image)
return 0;
}
-static const struct vm_special_mapping vvar_mapping;
struct linux_binprm;
static vm_fault_t vdso_fault(const struct vm_special_mapping *sm,
@@ -98,99 +91,6 @@ static int vdso_mremap(const struct vm_special_mapping *sm,
return 0;
}
-#ifdef CONFIG_TIME_NS
-/*
- * The vvar page layout depends on whether a task belongs to the root or
- * non-root time namespace. Whenever a task changes its namespace, the VVAR
- * page tables are cleared and then they will re-faulted with a
- * corresponding layout.
- * See also the comment near timens_setup_vdso_data() for details.
- */
-int vdso_join_timens(struct task_struct *task, struct time_namespace *ns)
-{
- struct mm_struct *mm = task->mm;
- struct vm_area_struct *vma;
- VMA_ITERATOR(vmi, mm, 0);
-
- mmap_read_lock(mm);
- for_each_vma(vmi, vma) {
- if (vma_is_special_mapping(vma, &vvar_mapping))
- zap_vma_pages(vma);
- }
- mmap_read_unlock(mm);
-
- return 0;
-}
-#endif
-
-static vm_fault_t vvar_fault(const struct vm_special_mapping *sm,
- struct vm_area_struct *vma, struct vm_fault *vmf)
-{
- const struct vdso_image *image = vma->vm_mm->context.vdso_image;
- unsigned long pfn;
- long sym_offset;
-
- if (!image)
- return VM_FAULT_SIGBUS;
-
- sym_offset = (long)(vmf->pgoff << PAGE_SHIFT) +
- image->sym_vvar_start;
-
- /*
- * Sanity check: a symbol offset of zero means that the page
- * does not exist for this vdso image, not that the page is at
- * offset zero relative to the text mapping. This should be
- * impossible here, because sym_offset should only be zero for
- * the page past the end of the vvar mapping.
- */
- if (sym_offset == 0)
- return VM_FAULT_SIGBUS;
-
- if (sym_offset == image->sym_vvar_page) {
- struct page *timens_page = find_timens_vvar_page(vma);
-
- pfn = __pa_symbol(vdso_data) >> PAGE_SHIFT;
-
- /*
- * If a task belongs to a time namespace then a namespace
- * specific VVAR is mapped with the sym_vvar_page offset and
- * the real VVAR page is mapped with the sym_timens_page
- * offset.
- * See also the comment near timens_setup_vdso_data().
- */
- if (timens_page) {
- unsigned long addr;
- vm_fault_t err;
-
- /*
- * Optimization: inside time namespace pre-fault
- * VVAR page too. As on timens page there are only
- * offsets for clocks on VVAR, it'll be faulted
- * shortly by VDSO code.
- */
- addr = vmf->address + (image->sym_timens_page - sym_offset);
- err = vmf_insert_pfn(vma, addr, pfn);
- if (unlikely(err & VM_FAULT_ERROR))
- return err;
-
- pfn = page_to_pfn(timens_page);
- }
-
- return vmf_insert_pfn(vma, vmf->address, pfn);
-
- } else if (sym_offset == image->sym_timens_page) {
- struct page *timens_page = find_timens_vvar_page(vma);
-
- if (!timens_page)
- return VM_FAULT_SIGBUS;
-
- pfn = __pa_symbol(vdso_data) >> PAGE_SHIFT;
- return vmf_insert_pfn(vma, vmf->address, pfn);
- }
-
- return VM_FAULT_SIGBUS;
-}
-
static vm_fault_t vvar_vclock_fault(const struct vm_special_mapping *sm,
struct vm_area_struct *vma, struct vm_fault *vmf)
{
@@ -212,7 +112,6 @@ static vm_fault_t vvar_vclock_fault(const struct vm_special_mapping *sm,
case VDSO_PAGE_HVCLOCK_OFFSET:
{
unsigned long pfn = hv_get_tsc_pfn();
-
if (pfn && vclock_was_used(VDSO_CLOCKMODE_HVCLOCK))
return vmf_insert_pfn(vma, vmf->address, pfn);
break;
@@ -228,10 +127,6 @@ static const struct vm_special_mapping vdso_mapping = {
.fault = vdso_fault,
.mremap = vdso_mremap,
};
-static const struct vm_special_mapping vvar_mapping = {
- .name = "[vvar]",
- .fault = vvar_fault,
-};
static const struct vm_special_mapping vvar_vclock_mapping = {
.name = "[vvar_vclock]",
.fault = vvar_vclock_fault,
@@ -253,13 +148,13 @@ static int map_vdso(const struct vdso_image *image, unsigned long addr)
return -EINTR;
addr = get_unmapped_area(NULL, addr,
- image->size - image->sym_vvar_start, 0, 0);
+ image->size + __VDSO_PAGES * PAGE_SIZE, 0, 0);
if (IS_ERR_VALUE(addr)) {
ret = addr;
goto up_fail;
}
- text_start = addr - image->sym_vvar_start;
+ text_start = addr + __VDSO_PAGES * PAGE_SIZE;
/*
* MAYWRITE to allow gdb to COW and set breakpoints
@@ -276,13 +171,7 @@ static int map_vdso(const struct vdso_image *image, unsigned long addr)
goto up_fail;
}
- vma = _install_special_mapping(mm,
- addr,
- (__VVAR_PAGES - VDSO_NR_VCLOCK_PAGES) * PAGE_SIZE,
- VM_READ|VM_MAYREAD|VM_IO|VM_DONTDUMP|
- VM_PFNMAP,
- &vvar_mapping);
-
+ vma = vdso_install_vvar_mapping(mm, addr);
if (IS_ERR(vma)) {
ret = PTR_ERR(vma);
do_munmap(mm, text_start, image->size, NULL);
@@ -290,7 +179,7 @@ static int map_vdso(const struct vdso_image *image, unsigned long addr)
}
vma = _install_special_mapping(mm,
- addr + (__VVAR_PAGES - VDSO_NR_VCLOCK_PAGES) * PAGE_SIZE,
+ vma->vm_end,
VDSO_NR_VCLOCK_PAGES * PAGE_SIZE,
VM_READ|VM_MAYREAD|VM_IO|VM_DONTDUMP|
VM_PFNMAP,
@@ -327,7 +216,7 @@ int map_vdso_once(const struct vdso_image *image, unsigned long addr)
*/
for_each_vma(vmi, vma) {
if (vma_is_special_mapping(vma, &vdso_mapping) ||
- vma_is_special_mapping(vma, &vvar_mapping) ||
+ vma_is_special_mapping(vma, &vdso_vvar_mapping) ||
vma_is_special_mapping(vma, &vvar_vclock_mapping)) {
mmap_write_unlock(mm);
return -EEXIST;
diff --git a/arch/x86/include/asm/vdso/getrandom.h b/arch/x86/include/asm/vdso/getrandom.h
index 2bf9c0e970c3e7d2a2ddfcb1d007cb73da200494..af85539f6557b8e22f7c8fb142c5c83330219af1 100644
--- a/arch/x86/include/asm/vdso/getrandom.h
+++ b/arch/x86/include/asm/vdso/getrandom.h
@@ -27,16 +27,6 @@ static __always_inline ssize_t getrandom_syscall(void *buffer, size_t len, unsig
return ret;
}
-extern struct vdso_rng_data vdso_rng_data
- __attribute__((visibility("hidden")));
-
-static __always_inline const struct vdso_rng_data *__arch_get_vdso_rng_data(void)
-{
- if (IS_ENABLED(CONFIG_TIME_NS) && __arch_get_vdso_data()->clock_mode == VDSO_CLOCKMODE_TIMENS)
- return (void *)&vdso_rng_data + ((void *)&timens_page - (void *)__arch_get_vdso_data());
- return &vdso_rng_data;
-}
-
#endif /* !__ASSEMBLY__ */
#endif /* __ASM_VDSO_GETRANDOM_H */
diff --git a/arch/x86/include/asm/vdso/gettimeofday.h b/arch/x86/include/asm/vdso/gettimeofday.h
index 375a34b0f365792ec108381d7c7229f8351448f7..edec796832e08b73d6d58bda6408957048f4e80e 100644
--- a/arch/x86/include/asm/vdso/gettimeofday.h
+++ b/arch/x86/include/asm/vdso/gettimeofday.h
@@ -19,12 +19,6 @@
#include <asm/pvclock.h>
#include <clocksource/hyperv_timer.h>
-extern struct vdso_data vvar_page
- __attribute__((visibility("hidden")));
-
-extern struct vdso_data timens_page
- __attribute__((visibility("hidden")));
-
#define VDSO_HAS_TIME 1
#define VDSO_HAS_CLOCK_GETRES 1
@@ -59,14 +53,6 @@ extern struct ms_hyperv_tsc_page hvclock_page
__attribute__((visibility("hidden")));
#endif
-#ifdef CONFIG_TIME_NS
-static __always_inline
-const struct vdso_data *__arch_get_timens_vdso_data(const struct vdso_data *vd)
-{
- return &timens_page;
-}
-#endif
-
#ifndef BUILD_VDSO32
static __always_inline
@@ -250,7 +236,7 @@ static u64 vread_hvclock(void)
#endif
static inline u64 __arch_get_hw_counter(s32 clock_mode,
- const struct vdso_data *vd)
+ const struct vdso_time_data *vd)
{
if (likely(clock_mode == VDSO_CLOCKMODE_TSC))
return (u64)rdtsc_ordered() & S64_MAX;
@@ -275,12 +261,7 @@ static inline u64 __arch_get_hw_counter(s32 clock_mode,
return U64_MAX;
}
-static __always_inline const struct vdso_data *__arch_get_vdso_data(void)
-{
- return &vvar_page;
-}
-
-static inline bool arch_vdso_clocksource_ok(const struct vdso_data *vd)
+static inline bool arch_vdso_clocksource_ok(const struct vdso_time_data *vd)
{
return true;
}
@@ -319,7 +300,7 @@ static inline bool arch_vdso_cycles_ok(u64 cycles)
* declares everything with the MSB/Sign-bit set as invalid. Therefore the
* effective mask is S64_MAX.
*/
-static __always_inline u64 vdso_calc_ns(const struct vdso_data *vd, u64 cycles, u64 base)
+static __always_inline u64 vdso_calc_ns(const struct vdso_time_data *vd, u64 cycles, u64 base)
{
u64 delta = cycles - vd->cycle_last;
diff --git a/arch/x86/include/asm/vdso/vsyscall.h b/arch/x86/include/asm/vdso/vsyscall.h
index 37b4a70559a8228601203fe7b99b9ddfc3d94f1b..1cf31e4db2c4b58de3a81d3bbe109e18b95acc6f 100644
--- a/arch/x86/include/asm/vdso/vsyscall.h
+++ b/arch/x86/include/asm/vdso/vsyscall.h
@@ -2,8 +2,7 @@
#ifndef __ASM_VDSO_VSYSCALL_H
#define __ASM_VDSO_VSYSCALL_H
-#define __VDSO_RND_DATA_OFFSET 640
-#define __VVAR_PAGES 4
+#define __VDSO_PAGES 6
#define VDSO_NR_VCLOCK_PAGES 2
#define VDSO_PAGE_PVCLOCK_OFFSET 0
@@ -14,25 +13,6 @@
#include <vdso/datapage.h>
#include <asm/vgtod.h>
-extern struct vdso_data *vdso_data;
-
-/*
- * Update the vDSO data page to keep in sync with kernel timekeeping.
- */
-static __always_inline
-struct vdso_data *__x86_get_k_vdso_data(void)
-{
- return vdso_data;
-}
-#define __arch_get_k_vdso_data __x86_get_k_vdso_data
-
-static __always_inline
-struct vdso_rng_data *__x86_get_k_vdso_rng_data(void)
-{
- return (void *)vdso_data + __VDSO_RND_DATA_OFFSET;
-}
-#define __arch_get_k_vdso_rng_data __x86_get_k_vdso_rng_data
-
/* The asm-generic header needs to be included after the definitions above */
#include <asm-generic/vdso/vsyscall.h>
--
2.47.1
^ permalink raw reply related [flat|nested] 29+ messages in thread* [PATCH 14/17] x86/vdso/vdso2c: Remove page handling
2024-12-16 14:09 [PATCH 00/17] vDSO: Introduce generic data storage Thomas Weißschuh
` (12 preceding siblings ...)
2024-12-16 14:10 ` [PATCH 13/17] x86/vdso: " Thomas Weißschuh
@ 2024-12-16 14:10 ` Thomas Weißschuh
2024-12-16 14:10 ` [PATCH 15/17] vdso: Remove remnants of architecture-specific random state storage Thomas Weißschuh
` (2 subsequent siblings)
16 siblings, 0 replies; 29+ messages in thread
From: Thomas Weißschuh @ 2024-12-16 14:10 UTC (permalink / raw)
To: James E.J. Bottomley, Helge Deller, Andy Lutomirski,
Thomas Gleixner, Vincenzo Frascino, Anna-Maria Behnsen,
Frederic Weisbecker, Andrew Morton, Catalin Marinas, Will Deacon,
Theodore Ts'o, Jason A. Donenfeld, Paul Walmsley,
Palmer Dabbelt, Albert Ou, Huacai Chen, WANG Xuerui, Russell King,
Heiko Carstens, Vasily Gorbik, Alexander Gordeev,
Christian Borntraeger, Sven Schnelle, Thomas Bogendoerfer,
Michael Ellerman, Nicholas Piggin, Christophe Leroy, Naveen N Rao,
Madhavan Srinivasan, Ingo Molnar, Borislav Petkov, Dave Hansen,
x86, H. Peter Anvin, Arnd Bergmann
Cc: linux-parisc, linux-kernel, linux-arm-kernel, linux-riscv,
loongarch, linux-s390, linux-mips, linuxppc-dev, linux-arch,
Nam Cao, Thomas Weißschuh
The values are not used anymore.
Also the sanity checks performed by vdso2c can never trigger as they
only validate invariants already enforced by the linker script.
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
---
arch/x86/entry/vdso/vdso-layout.lds.S | 4 ----
arch/x86/entry/vdso/vdso2c.c | 21 ---------------------
arch/x86/entry/vdso/vdso2c.h | 20 --------------------
arch/x86/include/asm/vdso.h | 6 ------
4 files changed, 51 deletions(-)
diff --git a/arch/x86/entry/vdso/vdso-layout.lds.S b/arch/x86/entry/vdso/vdso-layout.lds.S
index 6a628ead49beb3480dc750786c31dc125dfd017a..f93944ec29e5318aea29e4ad83c3e7f76889e489 100644
--- a/arch/x86/entry/vdso/vdso-layout.lds.S
+++ b/arch/x86/entry/vdso/vdso-layout.lds.S
@@ -24,10 +24,6 @@ SECTIONS
pvclock_page = vclock_pages + VDSO_PAGE_PVCLOCK_OFFSET * PAGE_SIZE;
hvclock_page = vclock_pages + VDSO_PAGE_HVCLOCK_OFFSET * PAGE_SIZE;
- /* For compatibility with vdso2c */
- vvar_page = vdso_u_data;
- vvar_start = vdso_u_data;
-
. = SIZEOF_HEADERS;
.hash : { *(.hash) } :text
diff --git a/arch/x86/entry/vdso/vdso2c.c b/arch/x86/entry/vdso/vdso2c.c
index 90d15f2a72055e37f2ef4292096dd780a051bc84..f84e8f8fa5fe6d1bc680895dfef28fe9251a7fe3 100644
--- a/arch/x86/entry/vdso/vdso2c.c
+++ b/arch/x86/entry/vdso/vdso2c.c
@@ -69,33 +69,12 @@
const char *outfilename;
-/* Symbols that we need in vdso2c. */
-enum {
- sym_vvar_start,
- sym_vvar_page,
- sym_pvclock_page,
- sym_hvclock_page,
- sym_timens_page,
-};
-
-const int special_pages[] = {
- sym_vvar_page,
- sym_pvclock_page,
- sym_hvclock_page,
- sym_timens_page,
-};
-
struct vdso_sym {
const char *name;
bool export;
};
struct vdso_sym required_syms[] = {
- [sym_vvar_start] = {"vvar_start", true},
- [sym_vvar_page] = {"vvar_page", true},
- [sym_pvclock_page] = {"pvclock_page", true},
- [sym_hvclock_page] = {"hvclock_page", true},
- [sym_timens_page] = {"timens_page", true},
{"VDSO32_NOTE_MASK", true},
{"__kernel_vsyscall", true},
{"__kernel_sigreturn", true},
diff --git a/arch/x86/entry/vdso/vdso2c.h b/arch/x86/entry/vdso/vdso2c.h
index 67b3e37576a64a29ecbdc6fd75e410fc52a82e58..78ed1c1f28b92b97973f57d3f65b9c4d4694f462 100644
--- a/arch/x86/entry/vdso/vdso2c.h
+++ b/arch/x86/entry/vdso/vdso2c.h
@@ -150,26 +150,6 @@ static void BITSFUNC(go)(void *raw_addr, size_t raw_len,
}
}
- /* Validate mapping addresses. */
- for (i = 0; i < sizeof(special_pages) / sizeof(special_pages[0]); i++) {
- INT_BITS symval = syms[special_pages[i]];
-
- if (!symval)
- continue; /* The mapping isn't used; ignore it. */
-
- if (symval % 4096)
- fail("%s must be a multiple of 4096\n",
- required_syms[i].name);
- if (symval + 4096 < syms[sym_vvar_start])
- fail("%s underruns vvar_start\n",
- required_syms[i].name);
- if (symval + 4096 > 0)
- fail("%s is on the wrong side of the vdso text\n",
- required_syms[i].name);
- }
- if (syms[sym_vvar_start] % 4096)
- fail("vvar_begin must be a multiple of 4096\n");
-
if (!image_name) {
fwrite(stripped_addr, stripped_len, 1, outfile);
return;
diff --git a/arch/x86/include/asm/vdso.h b/arch/x86/include/asm/vdso.h
index d7f6592b74a94f6fecba59ce8f23eb3990843db4..80be0da733df43de7520bef69ad120ce05d37994 100644
--- a/arch/x86/include/asm/vdso.h
+++ b/arch/x86/include/asm/vdso.h
@@ -18,12 +18,6 @@ struct vdso_image {
unsigned long extable_base, extable_len;
const void *extable;
- long sym_vvar_start; /* Negative offset to the vvar area */
-
- long sym_vvar_page;
- long sym_pvclock_page;
- long sym_hvclock_page;
- long sym_timens_page;
long sym_VDSO32_NOTE_MASK;
long sym___kernel_sigreturn;
long sym___kernel_rt_sigreturn;
--
2.47.1
^ permalink raw reply related [flat|nested] 29+ messages in thread* [PATCH 15/17] vdso: Remove remnants of architecture-specific random state storage
2024-12-16 14:09 [PATCH 00/17] vDSO: Introduce generic data storage Thomas Weißschuh
` (13 preceding siblings ...)
2024-12-16 14:10 ` [PATCH 14/17] x86/vdso/vdso2c: Remove page handling Thomas Weißschuh
@ 2024-12-16 14:10 ` Thomas Weißschuh
2024-12-16 14:10 ` [PATCH 16/17] vdso: Remove remnants of architecture-specific time storage Thomas Weißschuh
2024-12-16 14:10 ` [PATCH 17/17] vdso: Remove kconfig symbol GENERIC_VDSO_DATA_STORE Thomas Weißschuh
16 siblings, 0 replies; 29+ messages in thread
From: Thomas Weißschuh @ 2024-12-16 14:10 UTC (permalink / raw)
To: James E.J. Bottomley, Helge Deller, Andy Lutomirski,
Thomas Gleixner, Vincenzo Frascino, Anna-Maria Behnsen,
Frederic Weisbecker, Andrew Morton, Catalin Marinas, Will Deacon,
Theodore Ts'o, Jason A. Donenfeld, Paul Walmsley,
Palmer Dabbelt, Albert Ou, Huacai Chen, WANG Xuerui, Russell King,
Heiko Carstens, Vasily Gorbik, Alexander Gordeev,
Christian Borntraeger, Sven Schnelle, Thomas Bogendoerfer,
Michael Ellerman, Nicholas Piggin, Christophe Leroy, Naveen N Rao,
Madhavan Srinivasan, Ingo Molnar, Borislav Petkov, Dave Hansen,
x86, H. Peter Anvin, Arnd Bergmann
Cc: linux-parisc, linux-kernel, linux-arm-kernel, linux-riscv,
loongarch, linux-s390, linux-mips, linuxppc-dev, linux-arch,
Nam Cao, Thomas Weißschuh
All users of the random vDSO are using the generic storage
implementation. Remove the now unnecessary compatibility accessor
functions and symbols.
Co-developed-by: Nam Cao <namcao@linutronix.de>
Signed-off-by: Nam Cao <namcao@linutronix.de>
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
---
drivers/char/random.c | 6 +++---
include/vdso/datapage.h | 8 --------
lib/vdso/getrandom.c | 4 ++--
3 files changed, 5 insertions(+), 13 deletions(-)
diff --git a/drivers/char/random.c b/drivers/char/random.c
index 23ee76bbb4aa728274bf9980a60b863216d88797..84efda7bede348401db2ed1c443e5ab2bc5dbd2b 100644
--- a/drivers/char/random.c
+++ b/drivers/char/random.c
@@ -278,7 +278,7 @@ static void crng_reseed(struct work_struct *work)
WRITE_ONCE(base_crng.generation, next_gen);
#ifdef CONFIG_VDSO_GETRANDOM
/* base_crng.generation's invalid value is ULONG_MAX, while
- * _vdso_rng_data.generation's invalid value is 0, so add one to the
+ * vdso_k_rng_data->generation's invalid value is 0, so add one to the
* former to arrive at the latter. Use smp_store_release so that this
* is ordered with the write above to base_crng.generation. Pairs with
* the smp_rmb() before the syscall in the vDSO code.
@@ -290,7 +290,7 @@ static void crng_reseed(struct work_struct *work)
* because the vDSO side only checks whether the value changed, without
* actually using or interpreting the value.
*/
- smp_store_release((unsigned long *)&__arch_get_k_vdso_rng_data()->generation, next_gen + 1);
+ smp_store_release((unsigned long *)&vdso_k_rng_data->generation, next_gen + 1);
#endif
if (!static_branch_likely(&crng_is_ready))
crng_init = CRNG_READY;
@@ -743,7 +743,7 @@ static void __cold _credit_init_bits(size_t bits)
queue_work(system_unbound_wq, &set_ready);
atomic_notifier_call_chain(&random_ready_notifier, 0, NULL);
#ifdef CONFIG_VDSO_GETRANDOM
- WRITE_ONCE(__arch_get_k_vdso_rng_data()->is_ready, true);
+ WRITE_ONCE(vdso_k_rng_data->is_ready, true);
#endif
wake_up_interruptible(&crng_init_wait);
kill_fasync(&fasync, SIGIO, POLL_IN);
diff --git a/include/vdso/datapage.h b/include/vdso/datapage.h
index b3227f1cf62895aa60ce0ca96afa42259f4771f9..0fc240c08e0f7cf596135eed18dd6f06011917d5 100644
--- a/include/vdso/datapage.h
+++ b/include/vdso/datapage.h
@@ -152,7 +152,6 @@ struct vdso_rng_data {
#ifndef CONFIG_GENERIC_VDSO_DATA_STORE
extern struct vdso_time_data _vdso_data[CS_BASES] __attribute__((visibility("hidden")));
extern struct vdso_time_data _timens_data[CS_BASES] __attribute__((visibility("hidden")));
-extern struct vdso_rng_data _vdso_rng_data __attribute__((visibility("hidden")));
#else
extern const struct vdso_time_data vdso_u_time_data[CS_BASES] __attribute__((visibility("hidden")));
extern const struct vdso_time_data vdso_u_timens_data[CS_BASES] __attribute__((visibility("hidden")));
@@ -211,13 +210,6 @@ static __always_inline const struct vdso_rng_data *__arch_get_vdso_u_rng_data(vo
{
return &vdso_u_rng_data;
}
-#define __arch_get_vdso_rng_data __arch_get_vdso_u_rng_data
-
-static __always_inline struct vdso_rng_data *__arch_get_vdso_k_rng_data(void)
-{
- return vdso_k_rng_data;
-}
-#define __arch_get_k_vdso_rng_data __arch_get_vdso_k_rng_data
#endif /* CONFIG_VDSO_GETRANDOM */
#endif /* CONFIG_GENERIC_VDSO_DATA_STORE */
diff --git a/lib/vdso/getrandom.c b/lib/vdso/getrandom.c
index 938ca539aaa64bc46280ef6dd17aa661126699eb..2ed019a76abca099de33326ef45101cf50f2f778 100644
--- a/lib/vdso/getrandom.c
+++ b/lib/vdso/getrandom.c
@@ -152,7 +152,7 @@ __cvdso_getrandom_data(const struct vdso_rng_data *rng_info, void *buffer, size_
/*
* Prevent the syscall from being reordered wrt current_generation. Pairs with the
- * smp_store_release(&_vdso_rng_data.generation) in random.c.
+ * smp_store_release(&vdso_k_rng_data.generation) in random.c.
*/
smp_rmb();
@@ -256,5 +256,5 @@ __cvdso_getrandom_data(const struct vdso_rng_data *rng_info, void *buffer, size_
static __always_inline ssize_t
__cvdso_getrandom(void *buffer, size_t len, unsigned int flags, void *opaque_state, size_t opaque_len)
{
- return __cvdso_getrandom_data(__arch_get_vdso_rng_data(), buffer, len, flags, opaque_state, opaque_len);
+ return __cvdso_getrandom_data(__arch_get_vdso_u_rng_data(), buffer, len, flags, opaque_state, opaque_len);
}
--
2.47.1
^ permalink raw reply related [flat|nested] 29+ messages in thread* [PATCH 16/17] vdso: Remove remnants of architecture-specific time storage
2024-12-16 14:09 [PATCH 00/17] vDSO: Introduce generic data storage Thomas Weißschuh
` (14 preceding siblings ...)
2024-12-16 14:10 ` [PATCH 15/17] vdso: Remove remnants of architecture-specific random state storage Thomas Weißschuh
@ 2024-12-16 14:10 ` Thomas Weißschuh
2024-12-16 14:10 ` [PATCH 17/17] vdso: Remove kconfig symbol GENERIC_VDSO_DATA_STORE Thomas Weißschuh
16 siblings, 0 replies; 29+ messages in thread
From: Thomas Weißschuh @ 2024-12-16 14:10 UTC (permalink / raw)
To: James E.J. Bottomley, Helge Deller, Andy Lutomirski,
Thomas Gleixner, Vincenzo Frascino, Anna-Maria Behnsen,
Frederic Weisbecker, Andrew Morton, Catalin Marinas, Will Deacon,
Theodore Ts'o, Jason A. Donenfeld, Paul Walmsley,
Palmer Dabbelt, Albert Ou, Huacai Chen, WANG Xuerui, Russell King,
Heiko Carstens, Vasily Gorbik, Alexander Gordeev,
Christian Borntraeger, Sven Schnelle, Thomas Bogendoerfer,
Michael Ellerman, Nicholas Piggin, Christophe Leroy, Naveen N Rao,
Madhavan Srinivasan, Ingo Molnar, Borislav Petkov, Dave Hansen,
x86, H. Peter Anvin, Arnd Bergmann
Cc: linux-parisc, linux-kernel, linux-arm-kernel, linux-riscv,
loongarch, linux-s390, linux-mips, linuxppc-dev, linux-arch,
Nam Cao, Thomas Weißschuh
All users of the random vDSO are using the generic storage
implementation. Remove the now unnecessary compatibility accessor
functions and symbols.
Co-developed-by: Nam Cao <namcao@linutronix.de>
Signed-off-by: Nam Cao <namcao@linutronix.de>
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
---
arch/arm/include/asm/vdso/vsyscall.h | 2 +-
include/asm-generic/vdso/vsyscall.h | 15 +++------
include/linux/time_namespace.h | 3 --
include/vdso/datapage.h | 24 +-------------
include/vdso/helpers.h | 8 ++---
kernel/time/namespace.c | 12 +++----
kernel/time/vsyscall.c | 19 ++++++-----
lib/vdso/gettimeofday.c | 62 ++++++++++++++++++------------------
lib/vdso_kernel/datastore.c | 10 +++---
9 files changed, 60 insertions(+), 95 deletions(-)
diff --git a/arch/arm/include/asm/vdso/vsyscall.h b/arch/arm/include/asm/vdso/vsyscall.h
index 6fe8f7113e9e533a8b7582f71611372c8db3b11f..828348083a6041f310a869e07be755b7baa4bdd0 100644
--- a/arch/arm/include/asm/vdso/vsyscall.h
+++ b/arch/arm/include/asm/vdso/vsyscall.h
@@ -14,7 +14,7 @@ void __arm_sync_vdso_time_data(struct vdso_time_data *vdata)
{
flush_dcache_page(virt_to_page(vdata));
}
-#define __arch_sync_vdso_data __arm_sync_vdso_time_data
+#define __arch_sync_vdso_time_data __arm_sync_vdso_time_data
/* The asm-generic header needs to be included after the definitions above */
#include <asm-generic/vdso/vsyscall.h>
diff --git a/include/asm-generic/vdso/vsyscall.h b/include/asm-generic/vdso/vsyscall.h
index 01dafd604188fb0512d21c4ce4b027f7da54f5a0..cb012850a9993bd0df3d118c5412540968adb36a 100644
--- a/include/asm-generic/vdso/vsyscall.h
+++ b/include/asm-generic/vdso/vsyscall.h
@@ -4,24 +4,17 @@
#ifndef __ASSEMBLY__
-#ifndef __arch_get_k_vdso_data
-static __always_inline struct vdso_data *__arch_get_k_vdso_data(void)
-{
- return NULL;
-}
-#endif /* __arch_get_k_vdso_data */
-
#ifndef __arch_update_vsyscall
-static __always_inline void __arch_update_vsyscall(struct vdso_data *vdata)
+static __always_inline void __arch_update_vsyscall(struct vdso_time_data *vdata)
{
}
#endif /* __arch_update_vsyscall */
-#ifndef __arch_sync_vdso_data
-static __always_inline void __arch_sync_vdso_data(struct vdso_data *vdata)
+#ifndef __arch_sync_vdso_time_data
+static __always_inline void __arch_sync_vdso_time_data(struct vdso_time_data *vdata)
{
}
-#endif /* __arch_sync_vdso_data */
+#endif /* __arch_sync_vdso_time_data */
#endif /* !__ASSEMBLY__ */
diff --git a/include/linux/time_namespace.h b/include/linux/time_namespace.h
index 4b81db223f5450218dfaf553b24195be9ba97c08..0b8b32bf0655109d368c5dacc23ca5efcbb5aa80 100644
--- a/include/linux/time_namespace.h
+++ b/include/linux/time_namespace.h
@@ -8,7 +8,6 @@
#include <linux/ns_common.h>
#include <linux/err.h>
#include <linux/time64.h>
-#include <vdso/datapage.h>
struct user_namespace;
extern struct user_namespace init_user_ns;
@@ -166,6 +165,4 @@ static inline ktime_t timens_ktime_to_host(clockid_t clockid, ktime_t tim)
}
#endif
-struct vdso_data *arch_get_vdso_data(void *vvar_page);
-
#endif /* _LINUX_TIMENS_H */
diff --git a/include/vdso/datapage.h b/include/vdso/datapage.h
index 0fc240c08e0f7cf596135eed18dd6f06011917d5..fe2368d9ae6a759101de80b1746f5cc221d7d142 100644
--- a/include/vdso/datapage.h
+++ b/include/vdso/datapage.h
@@ -128,8 +128,6 @@ struct vdso_time_data {
struct arch_vdso_time_data arch_data;
};
-#define vdso_data vdso_time_data
-
/**
* struct vdso_rng_data - vdso RNG state information
* @generation: counter representing the number of RNG reseeds
@@ -149,10 +147,7 @@ struct vdso_rng_data {
* With the hidden visibility, the compiler simply generates a PC-relative
* relocation, and this is what we need.
*/
-#ifndef CONFIG_GENERIC_VDSO_DATA_STORE
-extern struct vdso_time_data _vdso_data[CS_BASES] __attribute__((visibility("hidden")));
-extern struct vdso_time_data _timens_data[CS_BASES] __attribute__((visibility("hidden")));
-#else
+#ifdef CONFIG_GENERIC_VDSO_DATA_STORE
extern const struct vdso_time_data vdso_u_time_data[CS_BASES] __attribute__((visibility("hidden")));
extern const struct vdso_time_data vdso_u_timens_data[CS_BASES] __attribute__((visibility("hidden")));
extern const struct vdso_rng_data vdso_u_rng_data __attribute__((visibility("hidden")));
@@ -163,14 +158,6 @@ extern struct vdso_rng_data *vdso_k_rng_data;
extern struct vdso_arch_data *vdso_k_arch_data;
#endif
-/**
- * union vdso_data_store - Generic vDSO data page
- */
-union vdso_data_store {
- struct vdso_time_data data[CS_BASES];
- u8 page[1U << CONFIG_PAGE_SHIFT];
-};
-
#ifdef CONFIG_GENERIC_VDSO_DATA_STORE
#define VDSO_ARCH_DATA_SIZE ALIGN(sizeof(struct vdso_arch_data), PAGE_SIZE)
@@ -185,24 +172,16 @@ enum vdso_pages {
VDSO_NR_PAGES
};
-static __always_inline struct vdso_time_data *__arch_get_vdso_k_time_data(void)
-{
- return vdso_k_time_data;
-}
-#define __arch_get_k_vdso_data __arch_get_vdso_k_time_data
-
static __always_inline const struct vdso_time_data *__arch_get_vdso_u_time_data(void)
{
return vdso_u_time_data;
}
-#define __arch_get_vdso_data __arch_get_vdso_u_time_data
#ifdef CONFIG_TIME_NS
static __always_inline const struct vdso_time_data *__arch_get_vdso_u_timens_data(void)
{
return vdso_u_timens_data;
}
-#define __arch_get_timens_vdso_data(vd) __arch_get_vdso_u_timens_data()
#endif /* CONFIG_TIME_NS */
#ifdef CONFIG_VDSO_GETRANDOM
@@ -224,7 +203,6 @@ static __always_inline const struct vdso_arch_data *__arch_get_vdso_u_arch_data(
/*
* The generic vDSO implementation requires that gettimeofday.h
* provides:
- * - __arch_get_vdso_data(): to get the vdso datapage.
* - __arch_get_hw_counter(): to get the hw counter based on the
* clock_mode.
* - gettimeofday_fallback(): fallback for gettimeofday.
diff --git a/include/vdso/helpers.h b/include/vdso/helpers.h
index 3ddb03bb05cbeefc110adf0e672c2cd68848a0ae..41c3087070c7ab21d7adec04e6cd30c4b32ea221 100644
--- a/include/vdso/helpers.h
+++ b/include/vdso/helpers.h
@@ -7,7 +7,7 @@
#include <asm/barrier.h>
#include <vdso/datapage.h>
-static __always_inline u32 vdso_read_begin(const struct vdso_data *vd)
+static __always_inline u32 vdso_read_begin(const struct vdso_time_data *vd)
{
u32 seq;
@@ -18,7 +18,7 @@ static __always_inline u32 vdso_read_begin(const struct vdso_data *vd)
return seq;
}
-static __always_inline u32 vdso_read_retry(const struct vdso_data *vd,
+static __always_inline u32 vdso_read_retry(const struct vdso_time_data *vd,
u32 start)
{
u32 seq;
@@ -28,7 +28,7 @@ static __always_inline u32 vdso_read_retry(const struct vdso_data *vd,
return seq != start;
}
-static __always_inline void vdso_write_begin(struct vdso_data *vd)
+static __always_inline void vdso_write_begin(struct vdso_time_data *vd)
{
/*
* WRITE_ONCE() is required otherwise the compiler can validly tear
@@ -40,7 +40,7 @@ static __always_inline void vdso_write_begin(struct vdso_data *vd)
smp_wmb();
}
-static __always_inline void vdso_write_end(struct vdso_data *vd)
+static __always_inline void vdso_write_end(struct vdso_time_data *vd)
{
smp_wmb();
/*
diff --git a/kernel/time/namespace.c b/kernel/time/namespace.c
index 0775b9ec952af9639480db9480d06d12293d1ceb..12f55aa539adbc11cce4055f519dbeca8a73320c 100644
--- a/kernel/time/namespace.c
+++ b/kernel/time/namespace.c
@@ -165,18 +165,18 @@ static struct timens_offset offset_from_ts(struct timespec64 off)
* HVCLOCK
* VVAR
*
- * The check for vdso_data->clock_mode is in the unlikely path of
+ * The check for vdso_time_data->clock_mode is in the unlikely path of
* the seq begin magic. So for the non-timens case most of the time
* 'seq' is even, so the branch is not taken.
*
* If 'seq' is odd, i.e. a concurrent update is in progress, the extra check
- * for vdso_data->clock_mode is a non-issue. The task is spin waiting for the
+ * for vdso_time_data->clock_mode is a non-issue. The task is spin waiting for the
* update to finish and for 'seq' to become even anyway.
*
- * Timens page has vdso_data->clock_mode set to VDSO_CLOCKMODE_TIMENS which
+ * Timens page has vdso_time_data->clock_mode set to VDSO_CLOCKMODE_TIMENS which
* enforces the time namespace handling path.
*/
-static void timens_setup_vdso_data(struct vdso_data *vdata,
+static void timens_setup_vdso_data(struct vdso_time_data *vdata,
struct time_namespace *ns)
{
struct timens_offset *offset = vdata->offset;
@@ -219,7 +219,7 @@ static DEFINE_MUTEX(offset_lock);
static void timens_set_vvar_page(struct task_struct *task,
struct time_namespace *ns)
{
- struct vdso_data *vdata;
+ struct vdso_time_data *vdata;
unsigned int i;
if (ns == &init_time_ns)
@@ -235,7 +235,7 @@ static void timens_set_vvar_page(struct task_struct *task,
goto out;
ns->frozen_offsets = true;
- vdata = arch_get_vdso_data(page_address(ns->vvar_page));
+ vdata = page_address(ns->vvar_page);
for (i = 0; i < CS_BASES; i++)
timens_setup_vdso_data(&vdata[i], ns);
diff --git a/kernel/time/vsyscall.c b/kernel/time/vsyscall.c
index 05d3831431658227c080a89202f45e7a0af88895..418192296ef7dd3c1772d50f129e7838883cf00c 100644
--- a/kernel/time/vsyscall.c
+++ b/kernel/time/vsyscall.c
@@ -15,8 +15,7 @@
#include "timekeeping_internal.h"
-static inline void update_vdso_data(struct vdso_data *vdata,
- struct timekeeper *tk)
+static inline void update_vdso_time_data(struct vdso_time_data *vdata, struct timekeeper *tk)
{
struct vdso_timestamp *vdso_ts;
u64 nsec, sec;
@@ -77,7 +76,7 @@ static inline void update_vdso_data(struct vdso_data *vdata,
void update_vsyscall(struct timekeeper *tk)
{
- struct vdso_data *vdata = __arch_get_k_vdso_data();
+ struct vdso_time_data *vdata = vdso_k_time_data;
struct vdso_timestamp *vdso_ts;
s32 clock_mode;
u64 nsec;
@@ -117,23 +116,23 @@ void update_vsyscall(struct timekeeper *tk)
* update of the high resolution parts.
*/
if (clock_mode != VDSO_CLOCKMODE_NONE)
- update_vdso_data(vdata, tk);
+ update_vdso_time_data(vdata, tk);
__arch_update_vsyscall(vdata);
vdso_write_end(vdata);
- __arch_sync_vdso_data(vdata);
+ __arch_sync_vdso_time_data(vdata);
}
void update_vsyscall_tz(void)
{
- struct vdso_data *vdata = __arch_get_k_vdso_data();
+ struct vdso_time_data *vdata = vdso_k_time_data;
vdata[CS_HRES_COARSE].tz_minuteswest = sys_tz.tz_minuteswest;
vdata[CS_HRES_COARSE].tz_dsttime = sys_tz.tz_dsttime;
- __arch_sync_vdso_data(vdata);
+ __arch_sync_vdso_time_data(vdata);
}
/**
@@ -150,7 +149,7 @@ void update_vsyscall_tz(void)
*/
unsigned long vdso_update_begin(void)
{
- struct vdso_data *vdata = __arch_get_k_vdso_data();
+ struct vdso_time_data *vdata = vdso_k_time_data;
unsigned long flags = timekeeper_lock_irqsave();
vdso_write_begin(vdata);
@@ -167,9 +166,9 @@ unsigned long vdso_update_begin(void)
*/
void vdso_update_end(unsigned long flags)
{
- struct vdso_data *vdata = __arch_get_k_vdso_data();
+ struct vdso_time_data *vdata = vdso_k_time_data;
vdso_write_end(vdata);
- __arch_sync_vdso_data(vdata);
+ __arch_sync_vdso_time_data(vdata);
timekeeper_unlock_irqrestore(flags);
}
diff --git a/lib/vdso/gettimeofday.c b/lib/vdso/gettimeofday.c
index c01eaafd8041916878f3f407f7f4fc3e0a0611ca..c23ced571a9cc1df6966e0519c4458281cd5d448 100644
--- a/lib/vdso/gettimeofday.c
+++ b/lib/vdso/gettimeofday.c
@@ -14,12 +14,12 @@
#endif
#ifdef CONFIG_GENERIC_VDSO_OVERFLOW_PROTECT
-static __always_inline bool vdso_delta_ok(const struct vdso_data *vd, u64 delta)
+static __always_inline bool vdso_delta_ok(const struct vdso_time_data *vd, u64 delta)
{
return delta < vd->max_cycles;
}
#else
-static __always_inline bool vdso_delta_ok(const struct vdso_data *vd, u64 delta)
+static __always_inline bool vdso_delta_ok(const struct vdso_time_data *vd, u64 delta)
{
return true;
}
@@ -36,7 +36,7 @@ static __always_inline u64 vdso_shift_ns(u64 ns, u32 shift)
* Default implementation which works for all sane clocksources. That
* obviously excludes x86/TSC.
*/
-static __always_inline u64 vdso_calc_ns(const struct vdso_data *vd, u64 cycles, u64 base)
+static __always_inline u64 vdso_calc_ns(const struct vdso_time_data *vd, u64 cycles, u64 base)
{
u64 delta = (cycles - vd->cycle_last) & VDSO_DELTA_MASK(vd);
@@ -55,7 +55,7 @@ static inline bool __arch_vdso_hres_capable(void)
#endif
#ifndef vdso_clocksource_ok
-static inline bool vdso_clocksource_ok(const struct vdso_data *vd)
+static inline bool vdso_clocksource_ok(const struct vdso_time_data *vd)
{
return vd->clock_mode != VDSO_CLOCKMODE_NONE;
}
@@ -69,18 +69,18 @@ static inline bool vdso_cycles_ok(u64 cycles)
#endif
#ifdef CONFIG_TIME_NS
-static __always_inline int do_hres_timens(const struct vdso_data *vdns, clockid_t clk,
+static __always_inline int do_hres_timens(const struct vdso_time_data *vdns, clockid_t clk,
struct __kernel_timespec *ts)
{
const struct timens_offset *offs = &vdns->offset[clk];
const struct vdso_timestamp *vdso_ts;
- const struct vdso_data *vd;
+ const struct vdso_time_data *vd;
u64 cycles, ns;
u32 seq;
s64 sec;
vd = vdns - (clk == CLOCK_MONOTONIC_RAW ? CS_RAW : CS_HRES_COARSE);
- vd = __arch_get_timens_vdso_data(vd);
+ vd = __arch_get_vdso_u_timens_data();
if (clk != CLOCK_MONOTONIC_RAW)
vd = &vd[CS_HRES_COARSE];
else
@@ -115,19 +115,19 @@ static __always_inline int do_hres_timens(const struct vdso_data *vdns, clockid_
}
#else
static __always_inline
-const struct vdso_data *__arch_get_timens_vdso_data(const struct vdso_data *vd)
+const struct vdso_time_data *__arch_get_vdso_u_timens_data(void)
{
return NULL;
}
-static __always_inline int do_hres_timens(const struct vdso_data *vdns, clockid_t clk,
+static __always_inline int do_hres_timens(const struct vdso_time_data *vdns, clockid_t clk,
struct __kernel_timespec *ts)
{
return -EINVAL;
}
#endif
-static __always_inline int do_hres(const struct vdso_data *vd, clockid_t clk,
+static __always_inline int do_hres(const struct vdso_time_data *vd, clockid_t clk,
struct __kernel_timespec *ts)
{
const struct vdso_timestamp *vdso_ts = &vd->basetime[clk];
@@ -179,10 +179,10 @@ static __always_inline int do_hres(const struct vdso_data *vd, clockid_t clk,
}
#ifdef CONFIG_TIME_NS
-static __always_inline int do_coarse_timens(const struct vdso_data *vdns, clockid_t clk,
+static __always_inline int do_coarse_timens(const struct vdso_time_data *vdns, clockid_t clk,
struct __kernel_timespec *ts)
{
- const struct vdso_data *vd = __arch_get_timens_vdso_data(vdns);
+ const struct vdso_time_data *vd = __arch_get_vdso_u_timens_data();
const struct vdso_timestamp *vdso_ts = &vd->basetime[clk];
const struct timens_offset *offs = &vdns->offset[clk];
u64 nsec;
@@ -208,14 +208,14 @@ static __always_inline int do_coarse_timens(const struct vdso_data *vdns, clocki
return 0;
}
#else
-static __always_inline int do_coarse_timens(const struct vdso_data *vdns, clockid_t clk,
+static __always_inline int do_coarse_timens(const struct vdso_time_data *vdns, clockid_t clk,
struct __kernel_timespec *ts)
{
return -1;
}
#endif
-static __always_inline int do_coarse(const struct vdso_data *vd, clockid_t clk,
+static __always_inline int do_coarse(const struct vdso_time_data *vd, clockid_t clk,
struct __kernel_timespec *ts)
{
const struct vdso_timestamp *vdso_ts = &vd->basetime[clk];
@@ -242,7 +242,7 @@ static __always_inline int do_coarse(const struct vdso_data *vd, clockid_t clk,
}
static __always_inline int
-__cvdso_clock_gettime_common(const struct vdso_data *vd, clockid_t clock,
+__cvdso_clock_gettime_common(const struct vdso_time_data *vd, clockid_t clock,
struct __kernel_timespec *ts)
{
u32 msk;
@@ -269,7 +269,7 @@ __cvdso_clock_gettime_common(const struct vdso_data *vd, clockid_t clock,
}
static __maybe_unused int
-__cvdso_clock_gettime_data(const struct vdso_data *vd, clockid_t clock,
+__cvdso_clock_gettime_data(const struct vdso_time_data *vd, clockid_t clock,
struct __kernel_timespec *ts)
{
int ret = __cvdso_clock_gettime_common(vd, clock, ts);
@@ -282,12 +282,12 @@ __cvdso_clock_gettime_data(const struct vdso_data *vd, clockid_t clock,
static __maybe_unused int
__cvdso_clock_gettime(clockid_t clock, struct __kernel_timespec *ts)
{
- return __cvdso_clock_gettime_data(__arch_get_vdso_data(), clock, ts);
+ return __cvdso_clock_gettime_data(__arch_get_vdso_u_time_data(), clock, ts);
}
#ifdef BUILD_VDSO32
static __maybe_unused int
-__cvdso_clock_gettime32_data(const struct vdso_data *vd, clockid_t clock,
+__cvdso_clock_gettime32_data(const struct vdso_time_data *vd, clockid_t clock,
struct old_timespec32 *res)
{
struct __kernel_timespec ts;
@@ -308,12 +308,12 @@ __cvdso_clock_gettime32_data(const struct vdso_data *vd, clockid_t clock,
static __maybe_unused int
__cvdso_clock_gettime32(clockid_t clock, struct old_timespec32 *res)
{
- return __cvdso_clock_gettime32_data(__arch_get_vdso_data(), clock, res);
+ return __cvdso_clock_gettime32_data(__arch_get_vdso_u_time_data(), clock, res);
}
#endif /* BUILD_VDSO32 */
static __maybe_unused int
-__cvdso_gettimeofday_data(const struct vdso_data *vd,
+__cvdso_gettimeofday_data(const struct vdso_time_data *vd,
struct __kernel_old_timeval *tv, struct timezone *tz)
{
@@ -330,7 +330,7 @@ __cvdso_gettimeofday_data(const struct vdso_data *vd,
if (unlikely(tz != NULL)) {
if (IS_ENABLED(CONFIG_TIME_NS) &&
vd->clock_mode == VDSO_CLOCKMODE_TIMENS)
- vd = __arch_get_timens_vdso_data(vd);
+ vd = __arch_get_vdso_u_timens_data();
tz->tz_minuteswest = vd[CS_HRES_COARSE].tz_minuteswest;
tz->tz_dsttime = vd[CS_HRES_COARSE].tz_dsttime;
@@ -342,18 +342,18 @@ __cvdso_gettimeofday_data(const struct vdso_data *vd,
static __maybe_unused int
__cvdso_gettimeofday(struct __kernel_old_timeval *tv, struct timezone *tz)
{
- return __cvdso_gettimeofday_data(__arch_get_vdso_data(), tv, tz);
+ return __cvdso_gettimeofday_data(__arch_get_vdso_u_time_data(), tv, tz);
}
#ifdef VDSO_HAS_TIME
static __maybe_unused __kernel_old_time_t
-__cvdso_time_data(const struct vdso_data *vd, __kernel_old_time_t *time)
+__cvdso_time_data(const struct vdso_time_data *vd, __kernel_old_time_t *time)
{
__kernel_old_time_t t;
if (IS_ENABLED(CONFIG_TIME_NS) &&
vd->clock_mode == VDSO_CLOCKMODE_TIMENS)
- vd = __arch_get_timens_vdso_data(vd);
+ vd = __arch_get_vdso_u_timens_data();
t = READ_ONCE(vd[CS_HRES_COARSE].basetime[CLOCK_REALTIME].sec);
@@ -365,13 +365,13 @@ __cvdso_time_data(const struct vdso_data *vd, __kernel_old_time_t *time)
static __maybe_unused __kernel_old_time_t __cvdso_time(__kernel_old_time_t *time)
{
- return __cvdso_time_data(__arch_get_vdso_data(), time);
+ return __cvdso_time_data(__arch_get_vdso_u_time_data(), time);
}
#endif /* VDSO_HAS_TIME */
#ifdef VDSO_HAS_CLOCK_GETRES
static __maybe_unused
-int __cvdso_clock_getres_common(const struct vdso_data *vd, clockid_t clock,
+int __cvdso_clock_getres_common(const struct vdso_time_data *vd, clockid_t clock,
struct __kernel_timespec *res)
{
u32 msk;
@@ -383,7 +383,7 @@ int __cvdso_clock_getres_common(const struct vdso_data *vd, clockid_t clock,
if (IS_ENABLED(CONFIG_TIME_NS) &&
vd->clock_mode == VDSO_CLOCKMODE_TIMENS)
- vd = __arch_get_timens_vdso_data(vd);
+ vd = __arch_get_vdso_u_timens_data();
/*
* Convert the clockid to a bitmask and use it to check which
@@ -412,7 +412,7 @@ int __cvdso_clock_getres_common(const struct vdso_data *vd, clockid_t clock,
}
static __maybe_unused
-int __cvdso_clock_getres_data(const struct vdso_data *vd, clockid_t clock,
+int __cvdso_clock_getres_data(const struct vdso_time_data *vd, clockid_t clock,
struct __kernel_timespec *res)
{
int ret = __cvdso_clock_getres_common(vd, clock, res);
@@ -425,12 +425,12 @@ int __cvdso_clock_getres_data(const struct vdso_data *vd, clockid_t clock,
static __maybe_unused
int __cvdso_clock_getres(clockid_t clock, struct __kernel_timespec *res)
{
- return __cvdso_clock_getres_data(__arch_get_vdso_data(), clock, res);
+ return __cvdso_clock_getres_data(__arch_get_vdso_u_time_data(), clock, res);
}
#ifdef BUILD_VDSO32
static __maybe_unused int
-__cvdso_clock_getres_time32_data(const struct vdso_data *vd, clockid_t clock,
+__cvdso_clock_getres_time32_data(const struct vdso_time_data *vd, clockid_t clock,
struct old_timespec32 *res)
{
struct __kernel_timespec ts;
@@ -451,7 +451,7 @@ __cvdso_clock_getres_time32_data(const struct vdso_data *vd, clockid_t clock,
static __maybe_unused int
__cvdso_clock_getres_time32(clockid_t clock, struct old_timespec32 *res)
{
- return __cvdso_clock_getres_time32_data(__arch_get_vdso_data(),
+ return __cvdso_clock_getres_time32_data(__arch_get_vdso_u_time_data(),
clock, res);
}
#endif /* BUILD_VDSO32 */
diff --git a/lib/vdso_kernel/datastore.c b/lib/vdso_kernel/datastore.c
index 668cac8c4f80ac71d3f6de71e98e963bc65a1c15..17fbe4fe809fac8e41dcff4aba460187b9b46dac 100644
--- a/lib/vdso_kernel/datastore.c
+++ b/lib/vdso_kernel/datastore.c
@@ -11,7 +11,10 @@
/*
* The vDSO data page.
*/
-static union vdso_data_store vdso_time_data_store __page_aligned_data;
+static union {
+ struct vdso_time_data data[CS_BASES];
+ u8 page[PAGE_SIZE];
+} vdso_time_data_store __page_aligned_data;
struct vdso_time_data *vdso_k_time_data = vdso_time_data_store.data;
static_assert(sizeof(vdso_time_data_store) == PAGE_SIZE);
@@ -120,8 +123,3 @@ int vdso_join_timens(struct task_struct *task, struct time_namespace *ns)
return 0;
}
#endif
-
-struct vdso_time_data *arch_get_vdso_data(void *vvar_page)
-{
- return (struct vdso_time_data *)vvar_page;
-}
--
2.47.1
^ permalink raw reply related [flat|nested] 29+ messages in thread* [PATCH 17/17] vdso: Remove kconfig symbol GENERIC_VDSO_DATA_STORE
2024-12-16 14:09 [PATCH 00/17] vDSO: Introduce generic data storage Thomas Weißschuh
` (15 preceding siblings ...)
2024-12-16 14:10 ` [PATCH 16/17] vdso: Remove remnants of architecture-specific time storage Thomas Weißschuh
@ 2024-12-16 14:10 ` Thomas Weißschuh
16 siblings, 0 replies; 29+ messages in thread
From: Thomas Weißschuh @ 2024-12-16 14:10 UTC (permalink / raw)
To: James E.J. Bottomley, Helge Deller, Andy Lutomirski,
Thomas Gleixner, Vincenzo Frascino, Anna-Maria Behnsen,
Frederic Weisbecker, Andrew Morton, Catalin Marinas, Will Deacon,
Theodore Ts'o, Jason A. Donenfeld, Paul Walmsley,
Palmer Dabbelt, Albert Ou, Huacai Chen, WANG Xuerui, Russell King,
Heiko Carstens, Vasily Gorbik, Alexander Gordeev,
Christian Borntraeger, Sven Schnelle, Thomas Bogendoerfer,
Michael Ellerman, Nicholas Piggin, Christophe Leroy, Naveen N Rao,
Madhavan Srinivasan, Ingo Molnar, Borislav Petkov, Dave Hansen,
x86, H. Peter Anvin, Arnd Bergmann
Cc: linux-parisc, linux-kernel, linux-arm-kernel, linux-riscv,
loongarch, linux-s390, linux-mips, linuxppc-dev, linux-arch,
Nam Cao, Thomas Weißschuh
All users of HAVE_GENERIC_VDSO have been switched over to the generic
storage logic. The dedicated kconfig symbol can be removed and replaced
by HAVE_GENERIC_VDSO.
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
---
arch/Kconfig | 2 +-
arch/arm/mm/Kconfig | 1 -
arch/arm64/Kconfig | 1 -
arch/loongarch/Kconfig | 1 -
arch/mips/Kconfig | 1 -
arch/powerpc/Kconfig | 1 -
arch/riscv/Kconfig | 1 -
arch/s390/Kconfig | 1 -
arch/x86/Kconfig | 1 -
include/vdso/datapage.h | 8 +-------
lib/Kconfig | 1 -
lib/vdso_kernel/Kconfig | 7 -------
lib/vdso_kernel/Makefile | 2 +-
13 files changed, 3 insertions(+), 25 deletions(-)
diff --git a/arch/Kconfig b/arch/Kconfig
index 48f37e6c00674f433a0d6e6e05ce72c27cf000b7..63e20e5e779d5c6d786b90ccb139e16a23445fcb 100644
--- a/arch/Kconfig
+++ b/arch/Kconfig
@@ -1577,7 +1577,7 @@ config HAVE_SPARSE_SYSCALL_NR
related optimizations for a given architecture.
config ARCH_HAS_VDSO_ARCH_DATA
- depends on GENERIC_VDSO_DATA_STORE
+ depends on HAVE_GENERIC_VDSO
bool
config ARCH_HAS_VDSO_TIME_DATA
diff --git a/arch/arm/mm/Kconfig b/arch/arm/mm/Kconfig
index 5c1023a6d78c1b4db67b2d62b71af5a79b7e701f..2b6f50dd547840adecbe08e684ed8f1a032cd7c2 100644
--- a/arch/arm/mm/Kconfig
+++ b/arch/arm/mm/Kconfig
@@ -928,7 +928,6 @@ config VDSO
select GENERIC_TIME_VSYSCALL
select GENERIC_VDSO_32
select GENERIC_GETTIMEOFDAY
- select GENERIC_VDSO_DATA_STORE
help
Place in the process address space an ELF shared object
providing fast implementations of gettimeofday and
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index 1a4a78ec593328d6e6bceacc1abb0821eab988ca..100570a048c5e8892c0112704f9ca74c4fc55b27 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -159,7 +159,6 @@ config ARM64
select GENERIC_SMP_IDLE_THREAD
select GENERIC_TIME_VSYSCALL
select GENERIC_GETTIMEOFDAY
- select GENERIC_VDSO_DATA_STORE
select GENERIC_VDSO_TIME_NS
select HARDIRQS_SW_RESEND
select HAS_IOPORT
diff --git a/arch/loongarch/Kconfig b/arch/loongarch/Kconfig
index 6ec7ef705199fdd4039afd23ec9050a28aa894eb..4dffb5ccd46397eedd27870183a105688ab23c5e 100644
--- a/arch/loongarch/Kconfig
+++ b/arch/loongarch/Kconfig
@@ -105,7 +105,6 @@ config LOONGARCH
select GENERIC_SCHED_CLOCK
select GENERIC_SMP_IDLE_THREAD
select GENERIC_TIME_VSYSCALL
- select GENERIC_VDSO_DATA_STORE
select GENERIC_VDSO_TIME_NS
select GPIOLIB
select HAS_IOPORT
diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig
index 94fae59589ae80d590ac250b52ba30e9dd6eda32..467b10f4361aeb7aad0121f334eaa5d23351010c 100644
--- a/arch/mips/Kconfig
+++ b/arch/mips/Kconfig
@@ -49,7 +49,6 @@ config MIPS
select GENERIC_SMP_IDLE_THREAD
select GENERIC_IDLE_POLL_SETUP
select GENERIC_TIME_VSYSCALL
- select GENERIC_VDSO_DATA_STORE
select GUP_GET_PXX_LOW_HIGH if CPU_MIPS32 && PHYS_ADDR_T_64BIT
select HAS_IOPORT if !NO_IOPORT_MAP || ISA
select HAVE_ARCH_COMPILER_H
diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index 600fa3b917ee902d016f2a04376950a9dc49074f..744c09813c43736089e69d06541a7a7d48a4d6da 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -207,7 +207,6 @@ config PPC
select GENERIC_PTDUMP
select GENERIC_SMP_IDLE_THREAD
select GENERIC_TIME_VSYSCALL
- select GENERIC_VDSO_DATA_STORE
select GENERIC_VDSO_TIME_NS
select HAS_IOPORT if PCI
select HAVE_ARCH_AUDITSYSCALL
diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
index a42d74aa53fe7c18e76820499d0ae43cd3b0c0bd..25023e4bc41b2aa02242ed1fe31caa3031a3edd5 100644
--- a/arch/riscv/Kconfig
+++ b/arch/riscv/Kconfig
@@ -115,7 +115,6 @@ config RISCV
select GENERIC_SCHED_CLOCK
select GENERIC_SMP_IDLE_THREAD
select GENERIC_TIME_VSYSCALL if MMU && 64BIT
- select GENERIC_VDSO_DATA_STORE if HAVE_GENERIC_VDSO
select GENERIC_VDSO_TIME_NS if HAVE_GENERIC_VDSO
select HARDIRQS_SW_RESEND
select HAS_IOPORT if MMU
diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig
index 6472eb4c210f378eaa61ddff04a6abc2f4aa2940..0077969170e8b4ca4c99e87ec75f6ea94f3e8e00 100644
--- a/arch/s390/Kconfig
+++ b/arch/s390/Kconfig
@@ -158,7 +158,6 @@ config S390
select GENERIC_PTDUMP
select GENERIC_SMP_IDLE_THREAD
select GENERIC_TIME_VSYSCALL
- select GENERIC_VDSO_DATA_STORE
select GENERIC_VDSO_TIME_NS
select GENERIC_IOREMAP if PCI
select HAVE_ALIGNED_STRUCT_PAGE
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index e3d7f17dc414ca93d6e746dbc7f02afd2bc043a8..9d7bd0ae48c4260f4abb6dbedc696e3915c230ea 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -177,7 +177,6 @@ config X86
select GENERIC_SMP_IDLE_THREAD
select GENERIC_TIME_VSYSCALL
select GENERIC_GETTIMEOFDAY
- select GENERIC_VDSO_DATA_STORE
select GENERIC_VDSO_TIME_NS
select GENERIC_VDSO_OVERFLOW_PROTECT
select GUP_GET_PXX_LOW_HIGH if X86_PAE
diff --git a/include/vdso/datapage.h b/include/vdso/datapage.h
index fe2368d9ae6a759101de80b1746f5cc221d7d142..49b23b35df5fc0699ac7f34693b7de1201aa4486 100644
--- a/include/vdso/datapage.h
+++ b/include/vdso/datapage.h
@@ -29,7 +29,7 @@ struct arch_vdso_time_data {};
#if defined(CONFIG_ARCH_HAS_VDSO_ARCH_DATA)
#include <asm/vdso/arch_data.h>
-#elif defined(CONFIG_GENERIC_VDSO_DATA_STORE)
+#else
struct vdso_arch_data {
/* Needed for the generic code, never actually used at runtime */
char __unused;
@@ -147,7 +147,6 @@ struct vdso_rng_data {
* With the hidden visibility, the compiler simply generates a PC-relative
* relocation, and this is what we need.
*/
-#ifdef CONFIG_GENERIC_VDSO_DATA_STORE
extern const struct vdso_time_data vdso_u_time_data[CS_BASES] __attribute__((visibility("hidden")));
extern const struct vdso_time_data vdso_u_timens_data[CS_BASES] __attribute__((visibility("hidden")));
extern const struct vdso_rng_data vdso_u_rng_data __attribute__((visibility("hidden")));
@@ -156,9 +155,6 @@ extern const struct vdso_arch_data vdso_u_arch_data __attribute__((visibility("h
extern struct vdso_time_data *vdso_k_time_data;
extern struct vdso_rng_data *vdso_k_rng_data;
extern struct vdso_arch_data *vdso_k_arch_data;
-#endif
-
-#ifdef CONFIG_GENERIC_VDSO_DATA_STORE
#define VDSO_ARCH_DATA_SIZE ALIGN(sizeof(struct vdso_arch_data), PAGE_SIZE)
#define VDSO_ARCH_DATA_PAGES (VDSO_ARCH_DATA_SIZE >> PAGE_SHIFT)
@@ -191,8 +187,6 @@ static __always_inline const struct vdso_rng_data *__arch_get_vdso_u_rng_data(vo
}
#endif /* CONFIG_VDSO_GETRANDOM */
-#endif /* CONFIG_GENERIC_VDSO_DATA_STORE */
-
#ifdef CONFIG_ARCH_HAS_VDSO_ARCH_DATA
static __always_inline const struct vdso_arch_data *__arch_get_vdso_u_arch_data(void)
{
diff --git a/lib/Kconfig b/lib/Kconfig
index 7d59b2c10ce5ffab03378ead254d9f9017a4482f..5a318f753b2f44cb0a7905cc0092e81c133bc112 100644
--- a/lib/Kconfig
+++ b/lib/Kconfig
@@ -659,7 +659,6 @@ config UCS2_STRING
# generic vdso
#
source "lib/vdso/Kconfig"
-source "lib/vdso_kernel/Kconfig"
source "lib/fonts/Kconfig"
diff --git a/lib/vdso_kernel/Kconfig b/lib/vdso_kernel/Kconfig
deleted file mode 100644
index 0c7ade9b3ece67c0c0ca892544b9e29e53c860c4..0000000000000000000000000000000000000000
--- a/lib/vdso_kernel/Kconfig
+++ /dev/null
@@ -1,7 +0,0 @@
-# SPDX-License-Identifier: GPL-2.0
-
-config GENERIC_VDSO_DATA_STORE
- bool
- depends on HAVE_GENERIC_VDSO
- help
- Selected by architectures that use the generic vDSO data store.
diff --git a/lib/vdso_kernel/Makefile b/lib/vdso_kernel/Makefile
index 4826e49f9edbdb48506b50957584ed89bde5f37f..aadc987caa434ef99c1420c62bb71fde04a07603 100644
--- a/lib/vdso_kernel/Makefile
+++ b/lib/vdso_kernel/Makefile
@@ -1,3 +1,3 @@
# SPDX-License-Identifier: GPL-2.0
-obj-$(CONFIG_GENERIC_VDSO_DATA_STORE) += datastore.o
+obj-$(CONFIG_HAVE_GENERIC_VDSO) += datastore.o
--
2.47.1
^ permalink raw reply related [flat|nested] 29+ messages in thread