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* [PATCH v11 4/5] powerpc/vdso: Switch VDSO to generic C implementation.
From: Christophe Leroy @ 2020-08-25 13:09 UTC (permalink / raw)
  To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman, nathanl,
	anton
  Cc: linux-arch, arnd, linux-kernel, luto, tglx, vincenzo.frascino,
	linuxppc-dev
In-Reply-To: <cover.1598360789.git.christophe.leroy@csgroup.eu>

For VDSO32 on PPC64, we create a fake 32 bits config, on the same
principle as MIPS architecture, in order to get the correct parts of
the different asm header files.

With the C VDSO, the performance is slightly lower, but it is worth
it as it will ease maintenance and evolution, and also brings clocks
that are not supported with the ASM VDSO.

On an 8xx at 132 MHz, vdsotest with the ASM VDSO:
gettimeofday:    vdso: 828 nsec/call
clock-getres-realtime-coarse:    vdso: 391 nsec/call
clock-gettime-realtime-coarse:    vdso: 614 nsec/call
clock-getres-realtime:    vdso: 460 nsec/call
clock-gettime-realtime:    vdso: 876 nsec/call
clock-getres-monotonic-coarse:    vdso: 399 nsec/call
clock-gettime-monotonic-coarse:    vdso: 691 nsec/call
clock-getres-monotonic:    vdso: 460 nsec/call
clock-gettime-monotonic:    vdso: 1026 nsec/call

On an 8xx at 132 MHz, vdsotest with the C VDSO:
gettimeofday:    vdso: 955 nsec/call
clock-getres-realtime-coarse:    vdso: 545 nsec/call
clock-gettime-realtime-coarse:    vdso: 592 nsec/call
clock-getres-realtime:    vdso: 545 nsec/call
clock-gettime-realtime:    vdso: 941 nsec/call
clock-getres-monotonic-coarse:    vdso: 545 nsec/call
clock-gettime-monotonic-coarse:    vdso: 591 nsec/call
clock-getres-monotonic:    vdso: 545 nsec/call
clock-gettime-monotonic:    vdso: 940 nsec/call

It is even better for gettime with monotonic clocks.

Unsupported clocks with ASM VDSO:
clock-gettime-boottime:    vdso: 3851 nsec/call
clock-gettime-tai:    vdso: 3852 nsec/call
clock-gettime-monotonic-raw:    vdso: 3396 nsec/call

Same clocks with C VDSO:
clock-gettime-tai:    vdso: 941 nsec/call
clock-gettime-monotonic-raw:    vdso: 1001 nsec/call
clock-gettime-monotonic-coarse:    vdso: 591 nsec/call

On an 8321E at 333 MHz, vdsotest with the ASM VDSO:
gettimeofday:    vdso: 220 nsec/call
clock-getres-realtime-coarse:    vdso: 102 nsec/call
clock-gettime-realtime-coarse:    vdso: 178 nsec/call
clock-getres-realtime:    vdso: 129 nsec/call
clock-gettime-realtime:    vdso: 235 nsec/call
clock-getres-monotonic-coarse:    vdso: 105 nsec/call
clock-gettime-monotonic-coarse:    vdso: 208 nsec/call
clock-getres-monotonic:    vdso: 129 nsec/call
clock-gettime-monotonic:    vdso: 274 nsec/call

On an 8321E at 333 MHz, vdsotest with the C VDSO:
gettimeofday:    vdso: 272 nsec/call
clock-getres-realtime-coarse:    vdso: 160 nsec/call
clock-gettime-realtime-coarse:    vdso: 184 nsec/call
clock-getres-realtime:    vdso: 166 nsec/call
clock-gettime-realtime:    vdso: 281 nsec/call
clock-getres-monotonic-coarse:    vdso: 160 nsec/call
clock-gettime-monotonic-coarse:    vdso: 184 nsec/call
clock-getres-monotonic:    vdso: 169 nsec/call
clock-gettime-monotonic:    vdso: 275 nsec/call

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
v9:
- Rebased (Impact on arch/powerpc/kernel/vdso??/Makefile

v7:
- Split out preparatory changes in a new preceding patch
- Added -fasynchronous-unwind-tables to CC flags.

v6:
- Added missing prototypes in asm/vdso/gettimeofday.h for __c_kernel_ functions.
- Using STACK_FRAME_OVERHEAD instead of INT_FRAME_SIZE
- Rebased on powerpc/merge as of 7 Apr 2020
- Fixed build failure with gcc 9
- Added a patch to create asm/vdso/processor.h and more cpu_relax() in it

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
 arch/powerpc/Kconfig                       |   2 +
 arch/powerpc/include/asm/vdso/vsyscall.h   |  25 ++
 arch/powerpc/include/asm/vdso_datapage.h   |  40 +--
 arch/powerpc/kernel/asm-offsets.c          |  49 +---
 arch/powerpc/kernel/time.c                 |  91 +------
 arch/powerpc/kernel/vdso.c                 |   5 +-
 arch/powerpc/kernel/vdso32/Makefile        |  32 ++-
 arch/powerpc/kernel/vdso32/config-fake32.h |  34 +++
 arch/powerpc/kernel/vdso32/gettimeofday.S  | 291 +--------------------
 arch/powerpc/kernel/vdso64/Makefile        |  23 +-
 arch/powerpc/kernel/vdso64/gettimeofday.S  | 242 +----------------
 11 files changed, 143 insertions(+), 691 deletions(-)
 create mode 100644 arch/powerpc/include/asm/vdso/vsyscall.h
 create mode 100644 arch/powerpc/kernel/vdso32/config-fake32.h

diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index 1f48bbfb3ce9..5bd22f4b38c3 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -173,6 +173,7 @@ config PPC
 	select GENERIC_STRNCPY_FROM_USER
 	select GENERIC_STRNLEN_USER
 	select GENERIC_TIME_VSYSCALL
+	select GENERIC_GETTIMEOFDAY
 	select HAVE_ARCH_AUDITSYSCALL
 	select HAVE_ARCH_HUGE_VMAP		if PPC_BOOK3S_64 && PPC_RADIX_MMU
 	select HAVE_ARCH_JUMP_LABEL
@@ -203,6 +204,7 @@ config PPC
 	select HAVE_FUNCTION_GRAPH_TRACER
 	select HAVE_FUNCTION_TRACER
 	select HAVE_GCC_PLUGINS			if GCC_VERSION >= 50200   # plugin support on gcc <= 5.1 is buggy on PPC
+	select HAVE_GENERIC_VDSO
 	select HAVE_HW_BREAKPOINT		if PERF_EVENTS && (PPC_BOOK3S || PPC_8xx)
 	select HAVE_IDE
 	select HAVE_IOREMAP_PROT
diff --git a/arch/powerpc/include/asm/vdso/vsyscall.h b/arch/powerpc/include/asm/vdso/vsyscall.h
new file mode 100644
index 000000000000..c56a030c0623
--- /dev/null
+++ b/arch/powerpc/include/asm/vdso/vsyscall.h
@@ -0,0 +1,25 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __ASM_VDSO_VSYSCALL_H
+#define __ASM_VDSO_VSYSCALL_H
+
+#ifndef __ASSEMBLY__
+
+#include <linux/timekeeper_internal.h>
+#include <asm/vdso_datapage.h>
+
+/*
+ * Update the vDSO data page to keep in sync with kernel timekeeping.
+ */
+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
+
+/* The asm-generic header needs to be included after the definitions above */
+#include <asm-generic/vdso/vsyscall.h>
+
+#endif /* !__ASSEMBLY__ */
+
+#endif /* __ASM_VDSO_VSYSCALL_H */
diff --git a/arch/powerpc/include/asm/vdso_datapage.h b/arch/powerpc/include/asm/vdso_datapage.h
index b9ef6cf50ea5..c4d320504d26 100644
--- a/arch/powerpc/include/asm/vdso_datapage.h
+++ b/arch/powerpc/include/asm/vdso_datapage.h
@@ -36,6 +36,7 @@
 
 #include <linux/unistd.h>
 #include <linux/time.h>
+#include <vdso/datapage.h>
 
 #define SYSCALL_MAP_SIZE      ((NR_syscalls + 31) / 32)
 
@@ -45,7 +46,7 @@
 
 #ifdef CONFIG_PPC64
 
-struct vdso_data {
+struct vdso_arch_data {
 	__u8  eye_catcher[16];		/* Eyecatcher: SYSTEMCFG:PPC64	0x00 */
 	struct {			/* Systemcfg version numbers	     */
 		__u32 major;		/* Major number			0x10 */
@@ -59,13 +60,13 @@ struct vdso_data {
 	__u32 processor;		/* Processor type		0x1C */
 	__u64 processorCount;		/* # of physical processors	0x20 */
 	__u64 physicalMemorySize;	/* Size of real memory(B)	0x28 */
-	__u64 tb_orig_stamp;		/* Timebase at boot		0x30 */
+	__u64 tb_orig_stamp;		/* (NU) Timebase at boot	0x30 */
 	__u64 tb_ticks_per_sec;		/* Timebase tics / sec		0x38 */
-	__u64 tb_to_xs;			/* Inverse of TB to 2^20	0x40 */
-	__u64 stamp_xsec;		/*				0x48 */
-	__u64 tb_update_count;		/* Timebase atomicity ctr	0x50 */
-	__u32 tz_minuteswest;		/* Minutes west of Greenwich	0x58 */
-	__u32 tz_dsttime;		/* Type of dst correction	0x5C */
+	__u64 tb_to_xs;			/* (NU) Inverse of TB to 2^20	0x40 */
+	__u64 stamp_xsec;		/* (NU)				0x48 */
+	__u64 tb_update_count;		/* (NU) Timebase atomicity ctr	0x50 */
+	__u32 tz_minuteswest;		/* (NU) Min. west of Greenwich	0x58 */
+	__u32 tz_dsttime;		/* (NU) Type of dst correction	0x5C */
 	__u32 dcache_size;		/* L1 d-cache size		0x60 */
 	__u32 dcache_line_size;		/* L1 d-cache line size		0x64 */
 	__u32 icache_size;		/* L1 i-cache size		0x68 */
@@ -78,14 +79,10 @@ struct vdso_data {
 	__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 stamp_sec_fraction;		/* fractional seconds of stamp_xtime */
-	__s32 wtom_clock_nsec;			/* Wall to monotonic clock nsec */
-	__s64 wtom_clock_sec;			/* Wall to monotonic clock sec */
-	__s64 stamp_xtime_sec;			/* xtime secs as at tb_orig_stamp */
-	__s64 stamp_xtime_nsec;			/* xtime nsecs as at tb_orig_stamp */
-	__u32 hrtimer_res;			/* hrtimer resolution */
    	__u32 syscall_map_64[SYSCALL_MAP_SIZE]; /* map of syscalls  */
    	__u32 syscall_map_32[SYSCALL_MAP_SIZE]; /* map of syscalls */
+
+	struct vdso_data data[CS_BASES];
 };
 
 #else /* CONFIG_PPC64 */
@@ -93,26 +90,15 @@ struct vdso_data {
 /*
  * And here is the simpler 32 bits version
  */
-struct vdso_data {
-	__u64 tb_orig_stamp;		/* Timebase at boot		0x30 */
+struct vdso_arch_data {
 	__u64 tb_ticks_per_sec;		/* Timebase tics / sec		0x38 */
-	__u64 tb_to_xs;			/* Inverse of TB to 2^20	0x40 */
-	__u64 stamp_xsec;		/*				0x48 */
-	__u32 tb_update_count;		/* Timebase atomicity ctr	0x50 */
-	__u32 tz_minuteswest;		/* Minutes west of Greenwich	0x58 */
-	__u32 tz_dsttime;		/* Type of dst correction	0x5C */
-	__s32 wtom_clock_sec;			/* Wall to monotonic clock */
-	__s32 wtom_clock_nsec;
-	__s32 stamp_xtime_sec;		/* xtime seconds as at tb_orig_stamp */
-	__s32 stamp_xtime_nsec;		/* xtime nsecs as at tb_orig_stamp */
-	__u32 stamp_sec_fraction;	/* fractional seconds of stamp_xtime */
-	__u32 hrtimer_res;		/* hrtimer resolution */
    	__u32 syscall_map_32[SYSCALL_MAP_SIZE]; /* map of syscalls */
+	struct vdso_data data[CS_BASES];
 };
 
 #endif /* CONFIG_PPC64 */
 
-extern struct vdso_data *vdso_data;
+extern struct vdso_arch_data *vdso_data;
 
 #else /* __ASSEMBLY__ */
 
diff --git a/arch/powerpc/kernel/asm-offsets.c b/arch/powerpc/kernel/asm-offsets.c
index 8711c2164b45..684260186dbf 100644
--- a/arch/powerpc/kernel/asm-offsets.c
+++ b/arch/powerpc/kernel/asm-offsets.c
@@ -397,47 +397,16 @@ int main(void)
 #endif /* ! CONFIG_PPC64 */
 
 	/* datapage offsets for use by vdso */
-	OFFSET(CFG_TB_ORIG_STAMP, vdso_data, tb_orig_stamp);
-	OFFSET(CFG_TB_TICKS_PER_SEC, vdso_data, tb_ticks_per_sec);
-	OFFSET(CFG_TB_TO_XS, vdso_data, tb_to_xs);
-	OFFSET(CFG_TB_UPDATE_COUNT, vdso_data, tb_update_count);
-	OFFSET(CFG_TZ_MINUTEWEST, vdso_data, tz_minuteswest);
-	OFFSET(CFG_TZ_DSTTIME, vdso_data, tz_dsttime);
-	OFFSET(CFG_SYSCALL_MAP32, vdso_data, syscall_map_32);
-	OFFSET(WTOM_CLOCK_SEC, vdso_data, wtom_clock_sec);
-	OFFSET(WTOM_CLOCK_NSEC, vdso_data, wtom_clock_nsec);
-	OFFSET(STAMP_XTIME_SEC, vdso_data, stamp_xtime_sec);
-	OFFSET(STAMP_XTIME_NSEC, vdso_data, stamp_xtime_nsec);
-	OFFSET(STAMP_SEC_FRAC, vdso_data, stamp_sec_fraction);
-	OFFSET(CLOCK_HRTIMER_RES, vdso_data, hrtimer_res);
+	OFFSET(VDSO_DATA_OFFSET, vdso_arch_data, data);
+	OFFSET(CFG_TB_TICKS_PER_SEC, vdso_arch_data, tb_ticks_per_sec);
+	OFFSET(CFG_SYSCALL_MAP32, vdso_arch_data, syscall_map_32);
 #ifdef CONFIG_PPC64
-	OFFSET(CFG_ICACHE_BLOCKSZ, vdso_data, icache_block_size);
-	OFFSET(CFG_DCACHE_BLOCKSZ, vdso_data, dcache_block_size);
-	OFFSET(CFG_ICACHE_LOGBLOCKSZ, vdso_data, icache_log_block_size);
-	OFFSET(CFG_DCACHE_LOGBLOCKSZ, vdso_data, dcache_log_block_size);
-	OFFSET(CFG_SYSCALL_MAP64, vdso_data, syscall_map_64);
-	OFFSET(TVAL64_TV_SEC, __kernel_old_timeval, tv_sec);
-	OFFSET(TVAL64_TV_USEC, __kernel_old_timeval, tv_usec);
-#endif
-	OFFSET(TSPC64_TV_SEC, __kernel_timespec, tv_sec);
-	OFFSET(TSPC64_TV_NSEC, __kernel_timespec, tv_nsec);
-	OFFSET(TVAL32_TV_SEC, old_timeval32, tv_sec);
-	OFFSET(TVAL32_TV_USEC, old_timeval32, tv_usec);
-	OFFSET(TSPC32_TV_SEC, old_timespec32, tv_sec);
-	OFFSET(TSPC32_TV_NSEC, old_timespec32, tv_nsec);
-	/* timeval/timezone offsets for use by vdso */
-	OFFSET(TZONE_TZ_MINWEST, timezone, tz_minuteswest);
-	OFFSET(TZONE_TZ_DSTTIME, timezone, tz_dsttime);
-
-	/* Other bits used by the vdso */
-	DEFINE(CLOCK_REALTIME, CLOCK_REALTIME);
-	DEFINE(CLOCK_MONOTONIC, CLOCK_MONOTONIC);
-	DEFINE(CLOCK_REALTIME_COARSE, CLOCK_REALTIME_COARSE);
-	DEFINE(CLOCK_MONOTONIC_COARSE, CLOCK_MONOTONIC_COARSE);
-	DEFINE(CLOCK_MAX, CLOCK_TAI);
-	DEFINE(NSEC_PER_SEC, NSEC_PER_SEC);
-	DEFINE(EINVAL, EINVAL);
-	DEFINE(KTIME_LOW_RES, KTIME_LOW_RES);
+	OFFSET(CFG_ICACHE_BLOCKSZ, vdso_arch_data, icache_block_size);
+	OFFSET(CFG_DCACHE_BLOCKSZ, vdso_arch_data, dcache_block_size);
+	OFFSET(CFG_ICACHE_LOGBLOCKSZ, vdso_arch_data, icache_log_block_size);
+	OFFSET(CFG_DCACHE_LOGBLOCKSZ, vdso_arch_data, dcache_log_block_size);
+	OFFSET(CFG_SYSCALL_MAP64, vdso_arch_data, syscall_map_64);
+#endif
 
 #ifdef CONFIG_BUG
 	DEFINE(BUG_ENTRY_SIZE, sizeof(struct bug_entry));
diff --git a/arch/powerpc/kernel/time.c b/arch/powerpc/kernel/time.c
index f85539ebb513..7a349bf8a595 100644
--- a/arch/powerpc/kernel/time.c
+++ b/arch/powerpc/kernel/time.c
@@ -91,6 +91,7 @@ static struct clocksource clocksource_timebase = {
 	.flags        = CLOCK_SOURCE_IS_CONTINUOUS,
 	.mask         = CLOCKSOURCE_MASK(64),
 	.read         = timebase_read,
+	.vdso_clock_mode	= VDSO_CLOCKMODE_ARCHTIMER,
 };
 
 #define DECREMENTER_DEFAULT_MAX 0x7FFFFFFF
@@ -857,95 +858,6 @@ static notrace u64 timebase_read(struct clocksource *cs)
 	return (u64)get_tb();
 }
 
-
-void update_vsyscall(struct timekeeper *tk)
-{
-	struct timespec64 xt;
-	struct clocksource *clock = tk->tkr_mono.clock;
-	u32 mult = tk->tkr_mono.mult;
-	u32 shift = tk->tkr_mono.shift;
-	u64 cycle_last = tk->tkr_mono.cycle_last;
-	u64 new_tb_to_xs, new_stamp_xsec;
-	u64 frac_sec;
-
-	if (clock != &clocksource_timebase)
-		return;
-
-	xt.tv_sec = tk->xtime_sec;
-	xt.tv_nsec = (long)(tk->tkr_mono.xtime_nsec >> tk->tkr_mono.shift);
-
-	/* Make userspace gettimeofday spin until we're done. */
-	++vdso_data->tb_update_count;
-	smp_mb();
-
-	/*
-	 * This computes ((2^20 / 1e9) * mult) >> shift as a
-	 * 0.64 fixed-point fraction.
-	 * The computation in the else clause below won't overflow
-	 * (as long as the timebase frequency is >= 1.049 MHz)
-	 * but loses precision because we lose the low bits of the constant
-	 * in the shift.  Note that 19342813113834067 ~= 2^(20+64) / 1e9.
-	 * For a shift of 24 the error is about 0.5e-9, or about 0.5ns
-	 * over a second.  (Shift values are usually 22, 23 or 24.)
-	 * For high frequency clocks such as the 512MHz timebase clock
-	 * on POWER[6789], the mult value is small (e.g. 32768000)
-	 * and so we can shift the constant by 16 initially
-	 * (295147905179 ~= 2^(20+64-16) / 1e9) and then do the
-	 * remaining shifts after the multiplication, which gives a
-	 * more accurate result (e.g. with mult = 32768000, shift = 24,
-	 * the error is only about 1.2e-12, or 0.7ns over 10 minutes).
-	 */
-	if (mult <= 62500000 && clock->shift >= 16)
-		new_tb_to_xs = ((u64) mult * 295147905179ULL) >> (clock->shift - 16);
-	else
-		new_tb_to_xs = (u64) mult * (19342813113834067ULL >> clock->shift);
-
-	/*
-	 * Compute the fractional second in units of 2^-32 seconds.
-	 * The fractional second is tk->tkr_mono.xtime_nsec >> tk->tkr_mono.shift
-	 * in nanoseconds, so multiplying that by 2^32 / 1e9 gives
-	 * it in units of 2^-32 seconds.
-	 * We assume shift <= 32 because clocks_calc_mult_shift()
-	 * generates shift values in the range 0 - 32.
-	 */
-	frac_sec = tk->tkr_mono.xtime_nsec << (32 - shift);
-	do_div(frac_sec, NSEC_PER_SEC);
-
-	/*
-	 * Work out new stamp_xsec value for any legacy users of systemcfg.
-	 * stamp_xsec is in units of 2^-20 seconds.
-	 */
-	new_stamp_xsec = frac_sec >> 12;
-	new_stamp_xsec += tk->xtime_sec * XSEC_PER_SEC;
-
-	/*
-	 * tb_update_count is used to allow the userspace gettimeofday code
-	 * to assure itself that it sees a consistent view of the tb_to_xs and
-	 * stamp_xsec variables.  It reads the tb_update_count, then reads
-	 * tb_to_xs and stamp_xsec and then reads tb_update_count again.  If
-	 * the two values of tb_update_count match and are even then the
-	 * tb_to_xs and stamp_xsec values are consistent.  If not, then it
-	 * loops back and reads them again until this criteria is met.
-	 */
-	vdso_data->tb_orig_stamp = cycle_last;
-	vdso_data->stamp_xsec = new_stamp_xsec;
-	vdso_data->tb_to_xs = new_tb_to_xs;
-	vdso_data->wtom_clock_sec = tk->wall_to_monotonic.tv_sec;
-	vdso_data->wtom_clock_nsec = tk->wall_to_monotonic.tv_nsec;
-	vdso_data->stamp_xtime_sec = xt.tv_sec;
-	vdso_data->stamp_xtime_nsec = xt.tv_nsec;
-	vdso_data->stamp_sec_fraction = frac_sec;
-	vdso_data->hrtimer_res = hrtimer_resolution;
-	smp_wmb();
-	++(vdso_data->tb_update_count);
-}
-
-void update_vsyscall_tz(void)
-{
-	vdso_data->tz_minuteswest = sys_tz.tz_minuteswest;
-	vdso_data->tz_dsttime = sys_tz.tz_dsttime;
-}
-
 static void __init clocksource_init(void)
 {
 	struct clocksource *clock;
@@ -1115,7 +1027,6 @@ void __init time_init(void)
 		sys_tz.tz_dsttime = 0;
 	}
 
-	vdso_data->tb_update_count = 0;
 	vdso_data->tb_ticks_per_sec = tb_ticks_per_sec;
 
 	/* initialise and enable the large decrementer (if we have one) */
diff --git a/arch/powerpc/kernel/vdso.c b/arch/powerpc/kernel/vdso.c
index 8dad44262e75..23208a051af5 100644
--- a/arch/powerpc/kernel/vdso.c
+++ b/arch/powerpc/kernel/vdso.c
@@ -17,6 +17,7 @@
 #include <linux/elf.h>
 #include <linux/security.h>
 #include <linux/memblock.h>
+#include <vdso/datapage.h>
 
 #include <asm/processor.h>
 #include <asm/mmu.h>
@@ -70,10 +71,10 @@ static int vdso_ready;
  * with it, it will become dynamically allocated
  */
 static union {
-	struct vdso_data	data;
+	struct vdso_arch_data	data;
 	u8			page[PAGE_SIZE];
 } vdso_data_store __page_aligned_data;
-struct vdso_data *vdso_data = &vdso_data_store.data;
+struct vdso_arch_data *vdso_data = &vdso_data_store.data;
 
 /* Format of the patch table */
 struct vdso_patch_def
diff --git a/arch/powerpc/kernel/vdso32/Makefile b/arch/powerpc/kernel/vdso32/Makefile
index 87ab1152d5ce..b922044236dd 100644
--- a/arch/powerpc/kernel/vdso32/Makefile
+++ b/arch/powerpc/kernel/vdso32/Makefile
@@ -2,7 +2,23 @@
 
 # List of files in the vdso, has to be asm only for now
 
-obj-vdso32 = sigtramp.o gettimeofday.o datapage.o cacheflush.o note.o getcpu.o
+ARCH_REL_TYPE_ABS := R_PPC_JUMP_SLOT|R_PPC_GLOB_DAT|R_PPC_ADDR32|R_PPC_ADDR24|R_PPC_ADDR16|R_PPC_ADDR16_LO|R_PPC_ADDR16_HI|R_PPC_ADDR16_HA|R_PPC_ADDR14|R_PPC_ADDR14_BRTAKEN|R_PPC_ADDR14_BRNTAKEN
+include $(srctree)/lib/vdso/Makefile
+
+obj-vdso32 = sigtramp.o datapage.o cacheflush.o note.o getcpu.o $(obj-vdso32-y)
+obj-vdso32 += gettimeofday.o
+
+ifneq ($(c-gettimeofday-y),)
+  ifdef CONFIG_PPC64
+    CFLAGS_vgettimeofday.o += -include $(srctree)/$(src)/config-fake32.h
+  endif
+  CFLAGS_vgettimeofday.o += -include $(c-gettimeofday-y)
+  CFLAGS_vgettimeofday.o += $(DISABLE_LATENT_ENTROPY_PLUGIN)
+  CFLAGS_vgettimeofday.o += $(call cc-option, -fno-stack-protector)
+  CFLAGS_vgettimeofday.o += -DDISABLE_BRANCH_PROFILING
+  CFLAGS_vgettimeofday.o += -ffreestanding -fasynchronous-unwind-tables
+  CFLAGS_REMOVE_vgettimeofday.o = $(CC_FLAGS_FTRACE)
+endif
 
 # Build rules
 
@@ -15,6 +31,7 @@ endif
 CC32FLAGS :=
 ifdef CONFIG_PPC64
 CC32FLAGS += -m32
+KBUILD_CFLAGS := $(filter-out -mcmodel=medium,$(KBUILD_CFLAGS))
 endif
 
 targets := $(obj-vdso32) vdso32.so vdso32.so.dbg
@@ -23,6 +40,7 @@ obj-vdso32 := $(addprefix $(obj)/, $(obj-vdso32))
 GCOV_PROFILE := n
 KCOV_INSTRUMENT := n
 UBSAN_SANITIZE := n
+KASAN_SANITIZE := n
 
 ccflags-y := -shared -fno-common -fno-builtin -nostdlib \
 	-Wl,-soname=linux-vdso32.so.1 -Wl,--hash-style=both
@@ -36,8 +54,8 @@ CPPFLAGS_vdso32.lds += -P -C -Upowerpc
 $(obj)/vdso32_wrapper.o : $(obj)/vdso32.so
 
 # link rule for the .so file, .lds has to be first
-$(obj)/vdso32.so.dbg: $(src)/vdso32.lds $(obj-vdso32) FORCE
-	$(call if_changed,vdso32ld)
+$(obj)/vdso32.so.dbg: $(src)/vdso32.lds $(obj-vdso32) $(obj)/vgettimeofday.o FORCE
+	$(call if_changed,vdso32ld_and_check)
 
 # strip rule for the .so file
 $(obj)/%.so: OBJCOPYFLAGS := -S
@@ -47,12 +65,16 @@ $(obj)/%.so: $(obj)/%.so.dbg FORCE
 # assembly rules for the .S files
 $(obj-vdso32): %.o: %.S FORCE
 	$(call if_changed_dep,vdso32as)
+$(obj)/vgettimeofday.o: %.o: %.c FORCE
+	$(call if_changed_dep,vdso32cc)
 
 # actual build commands
-quiet_cmd_vdso32ld = VDSO32L $@
-      cmd_vdso32ld = $(VDSOCC) $(c_flags) $(CC32FLAGS) -o $@ $(call cc-ldoption, -Wl$(comma)--orphan-handling=warn) -Wl,-T$(filter %.lds,$^) $(filter %.o,$^)
+quiet_cmd_vdso32ld_and_check = VDSO32L $@
+      cmd_vdso32ld_and_check = $(VDSOCC) $(c_flags) $(CC32FLAGS) -o $@ $(call cc-ldoption, -Wl$(comma)--orphan-handling=warn) -Wl,-T$(filter %.lds,$^) $(filter %.o,$^) ; $(cmd_vdso_check)
 quiet_cmd_vdso32as = VDSO32A $@
       cmd_vdso32as = $(VDSOCC) $(a_flags) $(CC32FLAGS) -c -o $@ $<
+quiet_cmd_vdso32cc = VDSO32C $@
+      cmd_vdso32cc = $(VDSOCC) $(c_flags) $(CC32FLAGS) -c -o $@ $<
 
 # install commands for the unstripped file
 quiet_cmd_vdso_install = INSTALL $@
diff --git a/arch/powerpc/kernel/vdso32/config-fake32.h b/arch/powerpc/kernel/vdso32/config-fake32.h
new file mode 100644
index 000000000000..e16041fc15c9
--- /dev/null
+++ b/arch/powerpc/kernel/vdso32/config-fake32.h
@@ -0,0 +1,34 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * In case of a 32 bit VDSO for a 64 bit kernel fake a 32 bit kernel
+ * configuration.
+ */
+
+#undef CONFIG_PPC64
+#undef CONFIG_64BIT
+#define CONFIG_PPC32
+#define CONFIG_32BIT 1
+#define CONFIG_GENERIC_ATOMIC64 1
+
+#ifdef CONFIG_PPC_BOOK3S_64
+#undef CONFIG_PPC_BOOK3S_64
+#undef CONFIG_PPC_PSERIES
+#define CONFIG_PPC_BOOK3S_32
+#else
+#define CONFIG_PPC_MMU_NOHASH_32
+#define CONFIG_FSL_BOOKE
+#endif
+
+#define CONFIG_TASK_SIZE	0
+#undef CONFIG_MMIOWB
+#undef CONFIG_PPC_SPLPAR
+#undef CONFIG_SPARSEMEM
+#undef CONFIG_PGTABLE_LEVELS
+#define CONFIG_PGTABLE_LEVELS	2
+#undef CONFIG_TRANSPARENT_HUGEPAGE
+#undef CONFIG_SPARSEMEM_VMEMMAP
+#undef CONFIG_FLATMEM
+#define CONFIG_FLATMEM
+#undef CONFIG_PPC_INDIRECT_MMIO
+#undef CONFIG_PPC_INDIRECT_PIO
+#undef CONFIG_EEH
diff --git a/arch/powerpc/kernel/vdso32/gettimeofday.S b/arch/powerpc/kernel/vdso32/gettimeofday.S
index e7f8f9f1b3f4..fd7b01c51281 100644
--- a/arch/powerpc/kernel/vdso32/gettimeofday.S
+++ b/arch/powerpc/kernel/vdso32/gettimeofday.S
@@ -12,13 +12,7 @@
 #include <asm/vdso_datapage.h>
 #include <asm/asm-offsets.h>
 #include <asm/unistd.h>
-
-/* Offset for the low 32-bit part of a field of long type */
-#ifdef CONFIG_PPC64
-#define LOPART	4
-#else
-#define LOPART	0
-#endif
+#include <asm/vdso/gettimeofday.h>
 
 	.text
 /*
@@ -28,32 +22,7 @@
  *
  */
 V_FUNCTION_BEGIN(__kernel_gettimeofday)
-  .cfi_startproc
-	mflr	r12
-  .cfi_register lr,r12
-
-	mr.	r10,r3			/* r10 saves tv */
-	mr	r11,r4			/* r11 saves tz */
-	get_datapage	r9, r0
-	beq	3f
-	LOAD_REG_IMMEDIATE(r7, 1000000)	/* load up USEC_PER_SEC */
-	bl	__do_get_tspec@local	/* get sec/usec from tb & kernel */
-	stw	r3,TVAL32_TV_SEC(r10)
-	stw	r4,TVAL32_TV_USEC(r10)
-
-3:	cmplwi	r11,0			/* check if tz is NULL */
-	mtlr	r12
-	crclr	cr0*4+so
-	li	r3,0
-	beqlr
-
-	lwz	r4,CFG_TZ_MINUTEWEST(r9)/* fill tz */
-	lwz	r5,CFG_TZ_DSTTIME(r9)
-	stw	r4,TZONE_TZ_MINWEST(r11)
-	stw	r5,TZONE_TZ_DSTTIME(r11)
-
-	blr
-  .cfi_endproc
+	cvdso_call __c_kernel_gettimeofday
 V_FUNCTION_END(__kernel_gettimeofday)
 
 /*
@@ -63,127 +32,7 @@ V_FUNCTION_END(__kernel_gettimeofday)
  *
  */
 V_FUNCTION_BEGIN(__kernel_clock_gettime)
-  .cfi_startproc
-	/* Check for supported clock IDs */
-	cmpli	cr0,r3,CLOCK_REALTIME
-	cmpli	cr1,r3,CLOCK_MONOTONIC
-	cror	cr0*4+eq,cr0*4+eq,cr1*4+eq
-
-	cmpli	cr5,r3,CLOCK_REALTIME_COARSE
-	cmpli	cr6,r3,CLOCK_MONOTONIC_COARSE
-	cror	cr5*4+eq,cr5*4+eq,cr6*4+eq
-
-	cror	cr0*4+eq,cr0*4+eq,cr5*4+eq
-	bne	cr0, .Lgettime_fallback
-
-	mflr	r12			/* r12 saves lr */
-  .cfi_register lr,r12
-	mr	r11,r4			/* r11 saves tp */
-	get_datapage	r9, r0
-	LOAD_REG_IMMEDIATE(r7, NSEC_PER_SEC)	/* load up NSEC_PER_SEC */
-	beq	cr5, .Lcoarse_clocks
-.Lprecise_clocks:
-	bl	__do_get_tspec@local	/* get sec/nsec from tb & kernel */
-	bne	cr1, .Lfinish		/* not monotonic -> all done */
-
-	/*
-	 * CLOCK_MONOTONIC
-	 */
-
-	/* now we must fixup using wall to monotonic. We need to snapshot
-	 * that value and do the counter trick again. Fortunately, we still
-	 * have the counter value in r8 that was returned by __do_get_xsec.
-	 * At this point, r3,r4 contain our sec/nsec values, r5 and r6
-	 * can be used, r7 contains NSEC_PER_SEC.
-	 */
-
-	lwz	r5,(WTOM_CLOCK_SEC+LOPART)(r9)
-	lwz	r6,WTOM_CLOCK_NSEC(r9)
-
-	/* We now have our offset in r5,r6. We create a fake dependency
-	 * on that value and re-check the counter
-	 */
-	or	r0,r6,r5
-	xor	r0,r0,r0
-	add	r9,r9,r0
-	lwz	r0,(CFG_TB_UPDATE_COUNT+LOPART)(r9)
-        cmpl    cr0,r8,r0		/* check if updated */
-	bne-	.Lprecise_clocks
-	b	.Lfinish_monotonic
-
-	/*
-	 * For coarse clocks we get data directly from the vdso data page, so
-	 * we don't need to call __do_get_tspec, but we still need to do the
-	 * counter trick.
-	 */
-.Lcoarse_clocks:
-	lwz	r8,(CFG_TB_UPDATE_COUNT+LOPART)(r9)
-	andi.	r0,r8,1                 /* pending update ? loop */
-	bne-	.Lcoarse_clocks
-	add	r9,r9,r0		/* r0 is already 0 */
-
-	/*
-	 * CLOCK_REALTIME_COARSE, below values are needed for MONOTONIC_COARSE
-	 * too
-	 */
-	lwz	r3,STAMP_XTIME_SEC+LOPART(r9)
-	lwz	r4,STAMP_XTIME_NSEC+LOPART(r9)
-	bne	cr6,1f
-
-	/* CLOCK_MONOTONIC_COARSE */
-	lwz	r5,(WTOM_CLOCK_SEC+LOPART)(r9)
-	lwz	r6,WTOM_CLOCK_NSEC(r9)
-
-	/* check if counter has updated */
-	or	r0,r6,r5
-1:	or	r0,r0,r3
-	or	r0,r0,r4
-	xor	r0,r0,r0
-	add	r3,r3,r0
-	lwz	r0,CFG_TB_UPDATE_COUNT+LOPART(r9)
-	cmpl	cr0,r0,r8               /* check if updated */
-	bne-	.Lcoarse_clocks
-
-	/* Counter has not updated, so continue calculating proper values for
-	 * sec and nsec if monotonic coarse, or just return with the proper
-	 * values for realtime.
-	 */
-	bne	cr6, .Lfinish
-
-	/* Calculate and store result. Note that this mimics the C code,
-	 * which may cause funny results if nsec goes negative... is that
-	 * possible at all ?
-	 */
-.Lfinish_monotonic:
-	add	r3,r3,r5
-	add	r4,r4,r6
-	cmpw	cr0,r4,r7
-	cmpwi	cr1,r4,0
-	blt	1f
-	subf	r4,r7,r4
-	addi	r3,r3,1
-1:	bge	cr1, .Lfinish
-	addi	r3,r3,-1
-	add	r4,r4,r7
-
-.Lfinish:
-	stw	r3,TSPC32_TV_SEC(r11)
-	stw	r4,TSPC32_TV_NSEC(r11)
-
-	mtlr	r12
-	crclr	cr0*4+so
-	li	r3,0
-	blr
-
-	/*
-	 * syscall fallback
-	 */
-.Lgettime_fallback:
-	li	r0,__NR_clock_gettime
-  .cfi_restore lr
-	sc
-	blr
-  .cfi_endproc
+	cvdso_call __c_kernel_clock_gettime
 V_FUNCTION_END(__kernel_clock_gettime)
 
 
@@ -194,37 +43,7 @@ V_FUNCTION_END(__kernel_clock_gettime)
  *
  */
 V_FUNCTION_BEGIN(__kernel_clock_getres)
-  .cfi_startproc
-	/* Check for supported clock IDs */
-	cmplwi	cr0, r3, CLOCK_MAX
-	cmpwi	cr1, r3, CLOCK_REALTIME_COARSE
-	cmpwi	cr7, r3, CLOCK_MONOTONIC_COARSE
-	bgt	cr0, 99f
-	LOAD_REG_IMMEDIATE(r5, KTIME_LOW_RES)
-	beq	cr1, 1f
-	beq	cr7, 1f
-
-	mflr	r12
-  .cfi_register lr,r12
-	get_datapage	r3, r0
-	lwz	r5, CLOCK_HRTIMER_RES(r3)
-	mtlr	r12
-1:	li	r3,0
-	cmpli	cr0,r4,0
-	crclr	cr0*4+so
-	beqlr
-	stw	r3,TSPC32_TV_SEC(r4)
-	stw	r5,TSPC32_TV_NSEC(r4)
-	blr
-
-	/*
-	 * syscall fallback
-	 */
-99:
-	li	r0,__NR_clock_getres
-	sc
-	blr
-  .cfi_endproc
+	cvdso_call __c_kernel_clock_getres
 V_FUNCTION_END(__kernel_clock_getres)
 
 
@@ -235,105 +54,5 @@ V_FUNCTION_END(__kernel_clock_getres)
  *
  */
 V_FUNCTION_BEGIN(__kernel_time)
-  .cfi_startproc
-	mflr	r12
-  .cfi_register lr,r12
-
-	mr	r11,r3			/* r11 holds t */
-	get_datapage	r9, r0
-
-	lwz	r3,STAMP_XTIME_SEC+LOPART(r9)
-
-	cmplwi	r11,0			/* check if t is NULL */
-	mtlr	r12
-	crclr	cr0*4+so
-	beqlr
-	stw	r3,0(r11)		/* store result at *t */
-	blr
-  .cfi_endproc
+	cvdso_call_time __c_kernel_time
 V_FUNCTION_END(__kernel_time)
-
-/*
- * This is the core of clock_gettime() and gettimeofday(),
- * it returns the current time in r3 (seconds) and r4.
- * On entry, r7 gives the resolution of r4, either USEC_PER_SEC
- * or NSEC_PER_SEC, giving r4 in microseconds or nanoseconds.
- * It expects the datapage ptr in r9 and doesn't clobber it.
- * It clobbers r0, r5 and r6.
- * On return, r8 contains the counter value that can be reused.
- * This clobbers cr0 but not any other cr field.
- */
-__do_get_tspec:
-  .cfi_startproc
-	/* Check for update count & load values. We use the low
-	 * order 32 bits of the update count
-	 */
-1:	lwz	r8,(CFG_TB_UPDATE_COUNT+LOPART)(r9)
-	andi.	r0,r8,1			/* pending update ? loop */
-	bne-	1b
-	xor	r0,r8,r8		/* create dependency */
-	add	r9,r9,r0
-
-	/* Load orig stamp (offset to TB) */
-	lwz	r5,CFG_TB_ORIG_STAMP(r9)
-	lwz	r6,(CFG_TB_ORIG_STAMP+4)(r9)
-
-	/* Get a stable TB value */
-2:	MFTBU(r3)
-	MFTBL(r4)
-	MFTBU(r0)
-	cmplw	cr0,r3,r0
-	bne-	2b
-
-	/* Subtract tb orig stamp and shift left 12 bits.
-	 */
-	subfc	r4,r6,r4
-	subfe	r0,r5,r3
-	slwi	r0,r0,12
-	rlwimi.	r0,r4,12,20,31
-	slwi	r4,r4,12
-
-	/*
-	 * Load scale factor & do multiplication.
-	 * We only use the high 32 bits of the tb_to_xs value.
-	 * Even with a 1GHz timebase clock, the high 32 bits of
-	 * tb_to_xs will be at least 4 million, so the error from
-	 * ignoring the low 32 bits will be no more than 0.25ppm.
-	 * The error will just make the clock run very very slightly
-	 * slow until the next time the kernel updates the VDSO data,
-	 * at which point the clock will catch up to the kernel's value,
-	 * so there is no long-term error accumulation.
-	 */
-	lwz	r5,CFG_TB_TO_XS(r9)	/* load values */
-	mulhwu	r4,r4,r5
-	li	r3,0
-
-	beq+	4f			/* skip high part computation if 0 */
-	mulhwu	r3,r0,r5
-	mullw	r5,r0,r5
-	addc	r4,r4,r5
-	addze	r3,r3
-4:
-	/* At this point, we have seconds since the xtime stamp
-	 * as a 32.32 fixed-point number in r3 and r4.
-	 * Load & add the xtime stamp.
-	 */
-	lwz	r5,STAMP_XTIME_SEC+LOPART(r9)
-	lwz	r6,STAMP_SEC_FRAC(r9)
-	addc	r4,r4,r6
-	adde	r3,r3,r5
-
-	/* We create a fake dependency on the result in r3/r4
-	 * and re-check the counter
-	 */
-	or	r6,r4,r3
-	xor	r0,r6,r6
-	add	r9,r9,r0
-	lwz	r0,(CFG_TB_UPDATE_COUNT+LOPART)(r9)
-        cmplw	cr0,r8,r0		/* check if updated */
-	bne-	1b
-
-	mulhwu	r4,r4,r7		/* convert to micro or nanoseconds */
-
-	blr
-  .cfi_endproc
diff --git a/arch/powerpc/kernel/vdso64/Makefile b/arch/powerpc/kernel/vdso64/Makefile
index 38c317f25141..7890d889f9c5 100644
--- a/arch/powerpc/kernel/vdso64/Makefile
+++ b/arch/powerpc/kernel/vdso64/Makefile
@@ -1,8 +1,20 @@
 # SPDX-License-Identifier: GPL-2.0
 # List of files in the vdso, has to be asm only for now
 
+ARCH_REL_TYPE_ABS := R_PPC_JUMP_SLOT|R_PPC_GLOB_DAT|R_PPC_ADDR32|R_PPC_ADDR24|R_PPC_ADDR16|R_PPC_ADDR16_LO|R_PPC_ADDR16_HI|R_PPC_ADDR16_HA|R_PPC_ADDR14|R_PPC_ADDR14_BRTAKEN|R_PPC_ADDR14_BRNTAKEN
+include $(srctree)/lib/vdso/Makefile
+
 obj-vdso64 = sigtramp.o gettimeofday.o datapage.o cacheflush.o note.o getcpu.o
 
+ifneq ($(c-gettimeofday-y),)
+  CFLAGS_vgettimeofday.o += -include $(c-gettimeofday-y)
+  CFLAGS_vgettimeofday.o += $(DISABLE_LATENT_ENTROPY_PLUGIN)
+  CFLAGS_vgettimeofday.o += $(call cc-option, -fno-stack-protector)
+  CFLAGS_vgettimeofday.o += -DDISABLE_BRANCH_PROFILING
+  CFLAGS_vgettimeofday.o += -ffreestanding -fasynchronous-unwind-tables
+  CFLAGS_REMOVE_vgettimeofday.o = $(CC_FLAGS_FTRACE)
+endif
+
 # Build rules
 
 targets := $(obj-vdso64) vdso64.so vdso64.so.dbg
@@ -11,6 +23,7 @@ obj-vdso64 := $(addprefix $(obj)/, $(obj-vdso64))
 GCOV_PROFILE := n
 KCOV_INSTRUMENT := n
 UBSAN_SANITIZE := n
+KASAN_SANITIZE := n
 
 ccflags-y := -shared -fno-common -fno-builtin -nostdlib \
 	-Wl,-soname=linux-vdso64.so.1 -Wl,--hash-style=both
@@ -20,12 +33,14 @@ obj-y += vdso64_wrapper.o
 extra-y += vdso64.lds
 CPPFLAGS_vdso64.lds += -P -C -U$(ARCH)
 
+$(obj)/vgettimeofday.o: %.o: %.c FORCE
+
 # Force dependency (incbin is bad)
 $(obj)/vdso64_wrapper.o : $(obj)/vdso64.so
 
 # link rule for the .so file, .lds has to be first
-$(obj)/vdso64.so.dbg: $(src)/vdso64.lds $(obj-vdso64) FORCE
-	$(call if_changed,vdso64ld)
+$(obj)/vdso64.so.dbg: $(src)/vdso64.lds $(obj-vdso64) $(obj)/vgettimeofday.o FORCE
+	$(call if_changed,vdso64ld_and_check)
 
 # strip rule for the .so file
 $(obj)/%.so: OBJCOPYFLAGS := -S
@@ -33,8 +48,8 @@ $(obj)/%.so: $(obj)/%.so.dbg FORCE
 	$(call if_changed,objcopy)
 
 # actual build commands
-quiet_cmd_vdso64ld = VDSO64L $@
-      cmd_vdso64ld = $(CC) $(c_flags) -o $@ -Wl,-T$(filter %.lds,$^) $(filter %.o,$^) $(call cc-ldoption, -Wl$(comma)--orphan-handling=warn)
+quiet_cmd_vdso64ld_and_check = VDSO64L $@
+      cmd_vdso64ld_and_check = $(CC) $(c_flags) -o $@ -Wl,-T$(filter %.lds,$^) $(filter %.o,$^) $(call cc-ldoption, -Wl$(comma)--orphan-handling=warn); $(cmd_vdso_check)
 
 # install commands for the unstripped file
 quiet_cmd_vdso_install = INSTALL $@
diff --git a/arch/powerpc/kernel/vdso64/gettimeofday.S b/arch/powerpc/kernel/vdso64/gettimeofday.S
index 20f8be40c653..d7a7bfb51081 100644
--- a/arch/powerpc/kernel/vdso64/gettimeofday.S
+++ b/arch/powerpc/kernel/vdso64/gettimeofday.S
@@ -12,6 +12,7 @@
 #include <asm/vdso_datapage.h>
 #include <asm/asm-offsets.h>
 #include <asm/unistd.h>
+#include <asm/vdso/gettimeofday.h>
 
 	.text
 /*
@@ -21,31 +22,7 @@
  *
  */
 V_FUNCTION_BEGIN(__kernel_gettimeofday)
-  .cfi_startproc
-	mflr	r12
-  .cfi_register lr,r12
-
-	mr	r11,r3			/* r11 holds tv */
-	mr	r10,r4			/* r10 holds tz */
-	get_datapage	r3, r0
-	cmpldi	r11,0			/* check if tv is NULL */
-	beq	2f
-	lis	r7,1000000@ha		/* load up USEC_PER_SEC */
-	addi	r7,r7,1000000@l
-	bl	V_LOCAL_FUNC(__do_get_tspec) /* get sec/us from tb & kernel */
-	std	r4,TVAL64_TV_SEC(r11)	/* store sec in tv */
-	std	r5,TVAL64_TV_USEC(r11)	/* store usec in tv */
-2:	cmpldi	r10,0			/* check if tz is NULL */
-	beq	1f
-	lwz	r4,CFG_TZ_MINUTEWEST(r3)/* fill tz */
-	lwz	r5,CFG_TZ_DSTTIME(r3)
-	stw	r4,TZONE_TZ_MINWEST(r10)
-	stw	r5,TZONE_TZ_DSTTIME(r10)
-1:	mtlr	r12
-	crclr	cr0*4+so
-	li	r3,0			/* always success */
-	blr
-  .cfi_endproc
+	cvdso_call __c_kernel_gettimeofday
 V_FUNCTION_END(__kernel_gettimeofday)
 
 
@@ -56,120 +33,7 @@ V_FUNCTION_END(__kernel_gettimeofday)
  *
  */
 V_FUNCTION_BEGIN(__kernel_clock_gettime)
-  .cfi_startproc
-	/* Check for supported clock IDs */
-	cmpwi	cr0,r3,CLOCK_REALTIME
-	cmpwi	cr1,r3,CLOCK_MONOTONIC
-	cror	cr0*4+eq,cr0*4+eq,cr1*4+eq
-
-	cmpwi	cr5,r3,CLOCK_REALTIME_COARSE
-	cmpwi	cr6,r3,CLOCK_MONOTONIC_COARSE
-	cror	cr5*4+eq,cr5*4+eq,cr6*4+eq
-
-	cror	cr0*4+eq,cr0*4+eq,cr5*4+eq
-	bne	cr0,99f
-
-	mflr	r12			/* r12 saves lr */
-  .cfi_register lr,r12
-	mr	r11,r4			/* r11 saves tp */
-	get_datapage	r3, r0
-	lis	r7,NSEC_PER_SEC@h	/* want nanoseconds */
-	ori	r7,r7,NSEC_PER_SEC@l
-	beq	cr5,70f
-50:	bl	V_LOCAL_FUNC(__do_get_tspec)	/* get time from tb & kernel */
-	bne	cr1,80f			/* if not monotonic, all done */
-
-	/*
-	 * CLOCK_MONOTONIC
-	 */
-
-	/* now we must fixup using wall to monotonic. We need to snapshot
-	 * that value and do the counter trick again. Fortunately, we still
-	 * have the counter value in r8 that was returned by __do_get_tspec.
-	 * At this point, r4,r5 contain our sec/nsec values.
-	 */
-
-	ld	r6,WTOM_CLOCK_SEC(r3)
-	lwa	r9,WTOM_CLOCK_NSEC(r3)
-
-	/* We now have our result in r6,r9. We create a fake dependency
-	 * on that result and re-check the counter
-	 */
-	or	r0,r6,r9
-	xor	r0,r0,r0
-	add	r3,r3,r0
-	ld	r0,CFG_TB_UPDATE_COUNT(r3)
-        cmpld   cr0,r0,r8		/* check if updated */
-	bne-	50b
-	b	78f
-
-	/*
-	 * For coarse clocks we get data directly from the vdso data page, so
-	 * we don't need to call __do_get_tspec, but we still need to do the
-	 * counter trick.
-	 */
-70:	ld      r8,CFG_TB_UPDATE_COUNT(r3)
-	andi.   r0,r8,1                 /* pending update ? loop */
-	bne-    70b
-	add     r3,r3,r0		/* r0 is already 0 */
-
-	/*
-	 * CLOCK_REALTIME_COARSE, below values are needed for MONOTONIC_COARSE
-	 * too
-	 */
-	ld      r4,STAMP_XTIME_SEC(r3)
-	ld      r5,STAMP_XTIME_NSEC(r3)
-	bne     cr6,75f
-
-	/* CLOCK_MONOTONIC_COARSE */
-	ld	r6,WTOM_CLOCK_SEC(r3)
-	lwa     r9,WTOM_CLOCK_NSEC(r3)
-
-	/* check if counter has updated */
-	or      r0,r6,r9
-75:	or	r0,r0,r4
-	or	r0,r0,r5
-	xor     r0,r0,r0
-	add     r3,r3,r0
-	ld      r0,CFG_TB_UPDATE_COUNT(r3)
-	cmpld   cr0,r0,r8               /* check if updated */
-	bne-    70b
-
-	/* Counter has not updated, so continue calculating proper values for
-	 * sec and nsec if monotonic coarse, or just return with the proper
-	 * values for realtime.
-	 */
-	bne     cr6,80f
-
-	/* Add wall->monotonic offset and check for overflow or underflow */
-78:	add     r4,r4,r6
-	add     r5,r5,r9
-	cmpd    cr0,r5,r7
-	cmpdi   cr1,r5,0
-	blt     79f
-	subf    r5,r7,r5
-	addi    r4,r4,1
-79:	bge     cr1,80f
-	addi    r4,r4,-1
-	add     r5,r5,r7
-
-80:	std	r4,TSPC64_TV_SEC(r11)
-	std	r5,TSPC64_TV_NSEC(r11)
-
-	mtlr	r12
-	crclr	cr0*4+so
-	li	r3,0
-	blr
-
-	/*
-	 * syscall fallback
-	 */
-99:
-	li	r0,__NR_clock_gettime
-  .cfi_restore lr
-	sc
-	blr
-  .cfi_endproc
+	cvdso_call __c_kernel_clock_gettime
 V_FUNCTION_END(__kernel_clock_gettime)
 
 
@@ -180,34 +44,7 @@ V_FUNCTION_END(__kernel_clock_gettime)
  *
  */
 V_FUNCTION_BEGIN(__kernel_clock_getres)
-  .cfi_startproc
-	/* Check for supported clock IDs */
-	cmpwi	cr0,r3,CLOCK_REALTIME
-	cmpwi	cr1,r3,CLOCK_MONOTONIC
-	cror	cr0*4+eq,cr0*4+eq,cr1*4+eq
-	bne	cr0,99f
-
-	mflr	r12
-  .cfi_register lr,r12
-	get_datapage	r3, r0
-	lwz	r5, CLOCK_HRTIMER_RES(r3)
-	mtlr	r12
-	li	r3,0
-	cmpldi	cr0,r4,0
-	crclr	cr0*4+so
-	beqlr
-	std	r3,TSPC64_TV_SEC(r4)
-	std	r5,TSPC64_TV_NSEC(r4)
-	blr
-
-	/*
-	 * syscall fallback
-	 */
-99:
-	li	r0,__NR_clock_getres
-	sc
-	blr
-  .cfi_endproc
+	cvdso_call __c_kernel_clock_getres
 V_FUNCTION_END(__kernel_clock_getres)
 
 /*
@@ -217,74 +54,5 @@ V_FUNCTION_END(__kernel_clock_getres)
  *
  */
 V_FUNCTION_BEGIN(__kernel_time)
-  .cfi_startproc
-	mflr	r12
-  .cfi_register lr,r12
-
-	mr	r11,r3			/* r11 holds t */
-	get_datapage	r3, r0
-
-	ld	r4,STAMP_XTIME_SEC(r3)
-
-	cmpldi	r11,0			/* check if t is NULL */
-	beq	2f
-	std	r4,0(r11)		/* store result at *t */
-2:	mtlr	r12
-	crclr	cr0*4+so
-	mr	r3,r4
-	blr
-  .cfi_endproc
+	cvdso_call_time __c_kernel_time
 V_FUNCTION_END(__kernel_time)
-
-
-/*
- * This is the core of clock_gettime() and gettimeofday(),
- * it returns the current time in r4 (seconds) and r5.
- * On entry, r7 gives the resolution of r5, either USEC_PER_SEC
- * or NSEC_PER_SEC, giving r5 in microseconds or nanoseconds.
- * It expects the datapage ptr in r3 and doesn't clobber it.
- * It clobbers r0, r6 and r9.
- * On return, r8 contains the counter value that can be reused.
- * This clobbers cr0 but not any other cr field.
- */
-V_FUNCTION_BEGIN(__do_get_tspec)
-  .cfi_startproc
-	/* check for update count & load values */
-1:	ld	r8,CFG_TB_UPDATE_COUNT(r3)
-	andi.	r0,r8,1			/* pending update ? loop */
-	bne-	1b
-	xor	r0,r8,r8		/* create dependency */
-	add	r3,r3,r0
-
-	/* Get TB & offset it. We use the MFTB macro which will generate
-	 * workaround code for Cell.
-	 */
-	MFTB(r6)
-	ld	r9,CFG_TB_ORIG_STAMP(r3)
-	subf	r6,r9,r6
-
-	/* Scale result */
-	ld	r5,CFG_TB_TO_XS(r3)
-	sldi	r6,r6,12		/* compute time since stamp_xtime */
-	mulhdu	r6,r6,r5		/* in units of 2^-32 seconds */
-
-	/* Add stamp since epoch */
-	ld	r4,STAMP_XTIME_SEC(r3)
-	lwz	r5,STAMP_SEC_FRAC(r3)
-	or	r0,r4,r5
-	or	r0,r0,r6
-	xor	r0,r0,r0
-	add	r3,r3,r0
-	ld	r0,CFG_TB_UPDATE_COUNT(r3)
-	cmpld   r0,r8			/* check if updated */
-	bne-	1b			/* reload if so */
-
-	/* convert to seconds & nanoseconds and add to stamp */
-	add	r6,r6,r5		/* add on fractional seconds of xtime */
-	mulhwu	r5,r6,r7		/* compute micro or nanoseconds and */
-	srdi	r6,r6,32		/* seconds since stamp_xtime */
-	clrldi	r5,r5,32
-	add	r4,r4,r6
-	blr
-  .cfi_endproc
-V_FUNCTION_END(__do_get_tspec)
-- 
2.25.0




^ permalink raw reply related

* [PATCH v11 5/5] powerpc/vdso: Provide __kernel_clock_gettime64() on vdso32
From: Christophe Leroy @ 2020-08-25 13:09 UTC (permalink / raw)
  To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman, nathanl,
	anton
  Cc: linux-arch, arnd, linux-kernel, luto, tglx, vincenzo.frascino,
	linuxppc-dev
In-Reply-To: <cover.1598360789.git.christophe.leroy@csgroup.eu>

Provides __kernel_clock_gettime64() on vdso32. This is the
64 bits version of __kernel_clock_gettime() which is
y2038 compliant.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
 arch/powerpc/kernel/vdso32/gettimeofday.S  | 9 +++++++++
 arch/powerpc/kernel/vdso32/vdso32.lds.S    | 1 +
 arch/powerpc/kernel/vdso32/vgettimeofday.c | 6 ++++++
 3 files changed, 16 insertions(+)

diff --git a/arch/powerpc/kernel/vdso32/gettimeofday.S b/arch/powerpc/kernel/vdso32/gettimeofday.S
index fd7b01c51281..a6e29f880e0e 100644
--- a/arch/powerpc/kernel/vdso32/gettimeofday.S
+++ b/arch/powerpc/kernel/vdso32/gettimeofday.S
@@ -35,6 +35,15 @@ V_FUNCTION_BEGIN(__kernel_clock_gettime)
 	cvdso_call __c_kernel_clock_gettime
 V_FUNCTION_END(__kernel_clock_gettime)
 
+/*
+ * Exact prototype of clock_gettime64()
+ *
+ * int __kernel_clock_gettime64(clockid_t clock_id, struct __timespec64 *ts);
+ *
+ */
+V_FUNCTION_BEGIN(__kernel_clock_gettime64)
+	cvdso_call __c_kernel_clock_gettime64
+V_FUNCTION_END(__kernel_clock_gettime64)
 
 /*
  * Exact prototype of clock_getres()
diff --git a/arch/powerpc/kernel/vdso32/vdso32.lds.S b/arch/powerpc/kernel/vdso32/vdso32.lds.S
index 4c985467a668..582c5b046cc9 100644
--- a/arch/powerpc/kernel/vdso32/vdso32.lds.S
+++ b/arch/powerpc/kernel/vdso32/vdso32.lds.S
@@ -148,6 +148,7 @@ VERSION
 #ifndef CONFIG_PPC_BOOK3S_601
 		__kernel_gettimeofday;
 		__kernel_clock_gettime;
+		__kernel_clock_gettime64;
 		__kernel_clock_getres;
 		__kernel_time;
 		__kernel_get_tbfreq;
diff --git a/arch/powerpc/kernel/vdso32/vgettimeofday.c b/arch/powerpc/kernel/vdso32/vgettimeofday.c
index 0b9ab4c22ef2..f7f71fecf4ed 100644
--- a/arch/powerpc/kernel/vdso32/vgettimeofday.c
+++ b/arch/powerpc/kernel/vdso32/vgettimeofday.c
@@ -11,6 +11,12 @@ int __c_kernel_clock_gettime(clockid_t clock, struct old_timespec32 *ts,
 	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)
+{
+	return __cvdso_clock_gettime_data(vd, clock, ts);
+}
+
 int __c_kernel_gettimeofday(struct __kernel_old_timeval *tv, struct timezone *tz,
 			    const struct vdso_data *vd)
 {
-- 
2.25.0


^ permalink raw reply related

* Re: [PATCH] powerpc: Update documentation of ISA versions for Power10
From: Jordan Niethe @ 2020-08-25 13:18 UTC (permalink / raw)
  To: Gabriel Paubert; +Cc: linuxppc-dev
In-Reply-To: <20200825124120.GA815@lt-gp.iram.es>

On Tue, Aug 25, 2020 at 10:41 PM Gabriel Paubert <paubert@iram.es> wrote:
>
> On Tue, Aug 25, 2020 at 09:45:07PM +1000, Jordan Niethe wrote:
> > Update the CPU to ISA Version Mapping document to include Power10 and
> > ISA v3.1.
> >
> > Signed-off-by: Jordan Niethe <jniethe5@gmail.com>
> > ---
> >  Documentation/powerpc/isa-versions.rst | 4 ++++
> >  1 file changed, 4 insertions(+)
> >
> > diff --git a/Documentation/powerpc/isa-versions.rst b/Documentation/powerpc/isa-versions.rst
> > index a363d8c1603c..72aff1eaaea1 100644
> > --- a/Documentation/powerpc/isa-versions.rst
> > +++ b/Documentation/powerpc/isa-versions.rst
> > @@ -7,6 +7,7 @@ Mapping of some CPU versions to relevant ISA versions.
> >  ========= ====================================================================
> >  CPU       Architecture version
> >  ========= ====================================================================
> > +Power10   Power ISA v3.1
> >  Power9    Power ISA v3.0B
> >  Power8    Power ISA v2.07
> >  Power7    Power ISA v2.06
> > @@ -32,6 +33,7 @@ Key Features
> >  ========== ==================
> >  CPU        VMX (aka. Altivec)
> >  ========== ==================
> > +Power10    Yes
> >  Power9     Yes
> >  Power8     Yes
> >  Power7     Yes
> > @@ -47,6 +49,7 @@ PPC970     Yes
> >  ========== ====
> >  CPU        VSX
> >  ========== ====
> > +Power10    Yes
> >  Power9     Yes
> >  Power8     Yes
> >  Power7     Yes
> > @@ -62,6 +65,7 @@ PPC970     No
> >  ========== ====================================
> >  CPU        Transactional Memory
> >  ========== ====================================
> > +Power10    Yes
> >  Power9     Yes (* see transactional_memory.txt)
> >  Power8     Yes
> >  Power7     No
>
> Huh?
>
> Transactional memory has been removed from the architecture for Power10.
Yeah you're right, I confused myself looking at CPU_FTRS_POWER10...
#define CPU_FTRS_POWER10 (CPU_FTR_LWSYNC | \
        CPU_FTR_PPCAS_ARCH_V2 | CPU_FTR_CTRL | CPU_FTR_ARCH_206 |\
        CPU_FTR_MMCRA | CPU_FTR_SMT | \
        CPU_FTR_COHERENT_ICACHE | \
        CPU_FTR_PURR | CPU_FTR_SPURR | CPU_FTR_REAL_LE | \
        CPU_FTR_DSCR | \
        CPU_FTR_STCX_CHECKS_ADDRESS | CPU_FTR_POPCNTB | CPU_FTR_POPCNTD | \
        CPU_FTR_CFAR | CPU_FTR_HVMODE | CPU_FTR_VMX_COPY | \
        CPU_FTR_DBELL | CPU_FTR_HAS_PPR | CPU_FTR_ARCH_207S | \
        CPU_FTR_TM_COMP | CPU_FTR_ARCH_300 | CPU_FTR_ARCH_31 | \
        CPU_FTR_DAWR | CPU_FTR_DAWR1)

CPU_FTR_TM_COMP should not be in there.

>
>         Gabriel
>
>

^ permalink raw reply

* Re: [PATCH net] ibmvnic fix NULL tx_pools and rx_tools issue at do_reset
From: Brian W Hart @ 2020-08-25 13:45 UTC (permalink / raw)
  To: Dany Madden; +Cc: netdev, Mingming Cao, linuxppc-dev, davem
In-Reply-To: <20200824234922.805858-1-drt@linux.ibm.com>

On Mon, Aug 24, 2020 at 07:49:23PM -0400, Dany Madden wrote:
> From: Mingming Cao <mmc@linux.vnet.ibm.com>
> 
> At the time of do_reset, ibmvnic tries to re-initalize the tx_pools
> and rx_pools to avoid re-allocating the long term buffer. However
> there is a window inside do_reset that the tx_pools and
> rx_pools were freed before re-initialized making it possible to deference
> null pointers.
> 
> This patch fixes this issue by checking that the tx_pool
> and rx_pool are not NULL after ibmvnic_login. If so, re-allocating
> the pools. This will avoid getting into calling reset_tx/rx_pools with
> NULL adapter tx_pools/rx_pools pointer. Also add null pointer check in
> reset_tx_pools and reset_rx_pools to safe handle NULL pointer case.
> 
> Signed-off-by: Mingming Cao <mmc@linux.vnet.ibm.com>
> Signed-off-by: Dany Madden <drt@linux.ibm.com>
> ---
>  drivers/net/ethernet/ibm/ibmvnic.c | 15 ++++++++++++++-
>  1 file changed, 14 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/net/ethernet/ibm/ibmvnic.c b/drivers/net/ethernet/ibm/ibmvnic.c
> index 5afb3c9c52d2..5ff48e55308b 100644
> --- a/drivers/net/ethernet/ibm/ibmvnic.c
> +++ b/drivers/net/ethernet/ibm/ibmvnic.c
> @@ -479,6 +479,9 @@ static int reset_rx_pools(struct ibmvnic_adapter *adapter)
>  	int i, j, rc;
>  	u64 *size_array;
> 
> +	if (!adapter->tx_pool)
> +		return -1;
> +

Should this one be testing rx_pool?

brian

>  	size_array = (u64 *)((u8 *)(adapter->login_rsp_buf) +
>  		be32_to_cpu(adapter->login_rsp_buf->off_rxadd_buff_size));
> 
> @@ -649,6 +652,9 @@ static int reset_tx_pools(struct ibmvnic_adapter *adapter)
>  	int tx_scrqs;
>  	int i, rc;
> 
> +	if (!adapter->tx_pool)
> +		return -1;
> +
>  	tx_scrqs = be32_to_cpu(adapter->login_rsp_buf->num_txsubm_subcrqs);
>  	for (i = 0; i < tx_scrqs; i++) {
>  		rc = reset_one_tx_pool(adapter, &adapter->tso_pool[i]);
> @@ -2011,7 +2017,10 @@ static int do_reset(struct ibmvnic_adapter *adapter,
>  		    adapter->req_rx_add_entries_per_subcrq !=
>  		    old_num_rx_slots ||
>  		    adapter->req_tx_entries_per_subcrq !=
> -		    old_num_tx_slots) {
> +		    old_num_tx_slots ||
> +			!adapter->rx_pool ||
> +			!adapter->tso_pool ||
> +			!adapter->tx_pool) {
>  			release_rx_pools(adapter);
>  			release_tx_pools(adapter);
>  			release_napi(adapter);
> @@ -2024,10 +2033,14 @@ static int do_reset(struct ibmvnic_adapter *adapter,
>  		} else {
>  			rc = reset_tx_pools(adapter);
>  			if (rc)
> +				netdev_dbg(adapter->netdev, "reset tx pools failed (%d)\n",
> +						rc);
>  				goto out;
> 
>  			rc = reset_rx_pools(adapter);
>  			if (rc)
> +				netdev_dbg(adapter->netdev, "reset rx pools failed (%d)\n",
> +						rc);
>  				goto out;
>  		}
>  		ibmvnic_disable_irqs(adapter);
> -- 
> 2.18.2
> 

^ permalink raw reply

* [PATCH v1 1/9] powerpc/vdso: Remove BUG_ON() in vdso_init()
From: Christophe Leroy @ 2020-08-25 13:53 UTC (permalink / raw)
  To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman
  Cc: linuxppc-dev, linux-kernel

If we are not able to allocate memory for the pagelists, bail out.

There is no reason to crash the machine, just have vdso init fail.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
This series is based on top of the series switching to C VDSO implementation,
but in fact only the last patch depends on that series and is not vital as
it is just afterwork cleanup.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
 arch/powerpc/kernel/vdso.c | 27 +++++++++++++++++----------
 1 file changed, 17 insertions(+), 10 deletions(-)

diff --git a/arch/powerpc/kernel/vdso.c b/arch/powerpc/kernel/vdso.c
index 23208a051af5..88a4a02ed4c4 100644
--- a/arch/powerpc/kernel/vdso.c
+++ b/arch/powerpc/kernel/vdso.c
@@ -747,20 +747,16 @@ static int __init vdso_init(void)
 	 * Initialize the vDSO images in memory, that is do necessary
 	 * fixups of vDSO symbols, locate trampolines, etc...
 	 */
-	if (vdso_setup()) {
-		printk(KERN_ERR "vDSO setup failure, not enabled !\n");
-		vdso32_pages = 0;
-#ifdef CONFIG_PPC64
-		vdso64_pages = 0;
-#endif
-		return 0;
-	}
+	if (vdso_setup())
+		goto setup_failed;
 
 #ifdef CONFIG_VDSO32
 	/* Make sure pages are in the correct state */
 	vdso32_pagelist = kcalloc(vdso32_pages + 2, sizeof(struct page *),
 				  GFP_KERNEL);
-	BUG_ON(vdso32_pagelist == NULL);
+	if (!vdso32_pagelist)
+		goto alloc_failed;
+
 	for (i = 0; i < vdso32_pages; i++) {
 		struct page *pg = virt_to_page(vdso32_kbase + i*PAGE_SIZE);
 		get_page(pg);
@@ -773,7 +769,9 @@ static int __init vdso_init(void)
 #ifdef CONFIG_PPC64
 	vdso64_pagelist = kcalloc(vdso64_pages + 2, sizeof(struct page *),
 				  GFP_KERNEL);
-	BUG_ON(vdso64_pagelist == NULL);
+	if (!vdso64_pagelist)
+		goto alloc_failed;
+
 	for (i = 0; i < vdso64_pages; i++) {
 		struct page *pg = virt_to_page(vdso64_kbase + i*PAGE_SIZE);
 		get_page(pg);
@@ -789,5 +787,14 @@ static int __init vdso_init(void)
 	vdso_ready = 1;
 
 	return 0;
+
+setup_failed:
+	pr_err("vDSO setup failure, not enabled !\n");
+alloc_failed:
+	vdso32_pages = 0;
+#ifdef CONFIG_PPC64
+	vdso64_pages = 0;
+#endif
+	return 0;
 }
 arch_initcall(vdso_init);
-- 
2.25.0


^ permalink raw reply related

* [PATCH v1 3/9] powerpc/vdso: Remove NULL termination element in vdso_pagelist
From: Christophe Leroy @ 2020-08-25 13:54 UTC (permalink / raw)
  To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman
  Cc: linuxppc-dev, linux-kernel
In-Reply-To: <df48ed76cf8a756a7f97ed42a1a39d0a404014bc.1598363608.git.christophe.leroy@csgroup.eu>

No need of a NULL last element in pagelists, install_special_mapping()
knows how long the list is.

Remove that element.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
 arch/powerpc/kernel/vdso.c | 10 ++++------
 1 file changed, 4 insertions(+), 6 deletions(-)

diff --git a/arch/powerpc/kernel/vdso.c b/arch/powerpc/kernel/vdso.c
index 3bc4d5b1980b..daef14a284a3 100644
--- a/arch/powerpc/kernel/vdso.c
+++ b/arch/powerpc/kernel/vdso.c
@@ -752,7 +752,7 @@ static int __init vdso_init(void)
 
 #ifdef CONFIG_VDSO32
 	/* Make sure pages are in the correct state */
-	vdso32_pagelist = kcalloc(vdso32_pages + 2, sizeof(struct page *),
+	vdso32_pagelist = kcalloc(vdso32_pages + 1, sizeof(struct page *),
 				  GFP_KERNEL);
 	if (!vdso32_pagelist)
 		goto alloc_failed;
@@ -760,12 +760,11 @@ static int __init vdso_init(void)
 	for (i = 0; i < vdso32_pages; i++)
 		vdso32_pagelist[i] = virt_to_page(vdso32_kbase + i * PAGE_SIZE);
 
-	vdso32_pagelist[i++] = virt_to_page(vdso_data);
-	vdso32_pagelist[i] = NULL;
+	vdso32_pagelist[i] = virt_to_page(vdso_data);
 #endif
 
 #ifdef CONFIG_PPC64
-	vdso64_pagelist = kcalloc(vdso64_pages + 2, sizeof(struct page *),
+	vdso64_pagelist = kcalloc(vdso64_pages + 1, sizeof(struct page *),
 				  GFP_KERNEL);
 	if (!vdso64_pagelist)
 		goto alloc_failed;
@@ -773,8 +772,7 @@ static int __init vdso_init(void)
 	for (i = 0; i < vdso64_pages; i++)
 		vdso64_pagelist[i] = virt_to_page(vdso64_kbase + i * PAGE_SIZE);
 
-	vdso64_pagelist[i++] = virt_to_page(vdso_data);
-	vdso64_pagelist[i] = NULL;
+	vdso64_pagelist[i] = virt_to_page(vdso_data);
 #endif /* CONFIG_PPC64 */
 
 	smp_wmb();
-- 
2.25.0


^ permalink raw reply related

* [PATCH v1 2/9] powerpc/vdso: Remove get_page() in vdso_pagelist initialization
From: Christophe Leroy @ 2020-08-25 13:54 UTC (permalink / raw)
  To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman
  Cc: linuxppc-dev, linux-kernel
In-Reply-To: <df48ed76cf8a756a7f97ed42a1a39d0a404014bc.1598363608.git.christophe.leroy@csgroup.eu>

Partly copied from commit 16fb1a9bec61 ("arm64: vdso: clean up
vdso_pagelist initialization").

No need to get_page() the vdso text/data - these are part of the
kernel image.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
 arch/powerpc/kernel/vdso.c | 18 ++++++------------
 1 file changed, 6 insertions(+), 12 deletions(-)

diff --git a/arch/powerpc/kernel/vdso.c b/arch/powerpc/kernel/vdso.c
index 88a4a02ed4c4..3bc4d5b1980b 100644
--- a/arch/powerpc/kernel/vdso.c
+++ b/arch/powerpc/kernel/vdso.c
@@ -757,11 +757,9 @@ static int __init vdso_init(void)
 	if (!vdso32_pagelist)
 		goto alloc_failed;
 
-	for (i = 0; i < vdso32_pages; i++) {
-		struct page *pg = virt_to_page(vdso32_kbase + i*PAGE_SIZE);
-		get_page(pg);
-		vdso32_pagelist[i] = pg;
-	}
+	for (i = 0; i < vdso32_pages; i++)
+		vdso32_pagelist[i] = virt_to_page(vdso32_kbase + i * PAGE_SIZE);
+
 	vdso32_pagelist[i++] = virt_to_page(vdso_data);
 	vdso32_pagelist[i] = NULL;
 #endif
@@ -772,17 +770,13 @@ static int __init vdso_init(void)
 	if (!vdso64_pagelist)
 		goto alloc_failed;
 
-	for (i = 0; i < vdso64_pages; i++) {
-		struct page *pg = virt_to_page(vdso64_kbase + i*PAGE_SIZE);
-		get_page(pg);
-		vdso64_pagelist[i] = pg;
-	}
+	for (i = 0; i < vdso64_pages; i++)
+		vdso64_pagelist[i] = virt_to_page(vdso64_kbase + i * PAGE_SIZE);
+
 	vdso64_pagelist[i++] = virt_to_page(vdso_data);
 	vdso64_pagelist[i] = NULL;
 #endif /* CONFIG_PPC64 */
 
-	get_page(virt_to_page(vdso_data));
-
 	smp_wmb();
 	vdso_ready = 1;
 
-- 
2.25.0


^ permalink raw reply related

* [PATCH v1 4/9] powerpc/vdso: Remove unnecessary ifdefs in vdso_pagelist initialization
From: Christophe Leroy @ 2020-08-25 13:54 UTC (permalink / raw)
  To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman
  Cc: linuxppc-dev, linux-kernel
In-Reply-To: <df48ed76cf8a756a7f97ed42a1a39d0a404014bc.1598363608.git.christophe.leroy@csgroup.eu>

No need of all those #ifdefs around the pagelist initialisation,
use IS_ENABLED(), GCC will kick out unused static variables.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
 arch/powerpc/kernel/vdso.c | 57 +++++++++++++++-----------------------
 1 file changed, 22 insertions(+), 35 deletions(-)

diff --git a/arch/powerpc/kernel/vdso.c b/arch/powerpc/kernel/vdso.c
index daef14a284a3..bbb69832fd46 100644
--- a/arch/powerpc/kernel/vdso.c
+++ b/arch/powerpc/kernel/vdso.c
@@ -51,15 +51,13 @@ static struct page **vdso32_pagelist;
 unsigned long vdso32_sigtramp;
 unsigned long vdso32_rt_sigtramp;
 
-#ifdef CONFIG_VDSO32
 extern char vdso32_start, vdso32_end;
-#endif
 
-#ifdef CONFIG_PPC64
 extern char vdso64_start, vdso64_end;
 static void *vdso64_kbase = &vdso64_start;
 static unsigned int vdso64_pages;
 static struct page **vdso64_pagelist;
+#ifdef CONFIG_PPC64
 unsigned long vdso64_rt_sigtramp;
 #endif /* CONFIG_PPC64 */
 
@@ -134,7 +132,6 @@ int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
 	if (!vdso_ready)
 		return 0;
 
-#ifdef CONFIG_PPC64
 	if (is_32bit_task()) {
 		vdso_pagelist = vdso32_pagelist;
 		vdso_pages = vdso32_pages;
@@ -149,11 +146,6 @@ int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
 		 */
 		vdso_base = 0;
 	}
-#else
-	vdso_pagelist = vdso32_pagelist;
-	vdso_pages = vdso32_pages;
-	vdso_base = VDSO32_MBASE;
-#endif
 
 	current->mm->context.vdso_base = 0;
 
@@ -718,16 +710,14 @@ static int __init vdso_init(void)
 	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;
+#endif /* CONFIG_PPC64 */
 
 	/*
 	 * Calculate the size of the 64 bits vDSO
 	 */
 	vdso64_pages = (&vdso64_end - &vdso64_start) >> PAGE_SHIFT;
 	DBG("vdso64_kbase: %p, 0x%x pages\n", vdso64_kbase, vdso64_pages);
-#endif /* CONFIG_PPC64 */
 
-
-#ifdef CONFIG_VDSO32
 	vdso32_kbase = &vdso32_start;
 
 	/*
@@ -735,8 +725,6 @@ static int __init vdso_init(void)
 	 */
 	vdso32_pages = (&vdso32_end - &vdso32_start) >> PAGE_SHIFT;
 	DBG("vdso32_kbase: %p, 0x%x pages\n", vdso32_kbase, vdso32_pages);
-#endif
-
 
 	/*
 	 * Setup the syscall map in the vDOS
@@ -750,30 +738,30 @@ static int __init vdso_init(void)
 	if (vdso_setup())
 		goto setup_failed;
 
-#ifdef CONFIG_VDSO32
-	/* Make sure pages are in the correct state */
-	vdso32_pagelist = kcalloc(vdso32_pages + 1, sizeof(struct page *),
-				  GFP_KERNEL);
-	if (!vdso32_pagelist)
-		goto alloc_failed;
+	if (IS_ENABLED(CONFIG_VDSO32)) {
+		/* Make sure pages are in the correct state */
+		vdso32_pagelist = kcalloc(vdso32_pages + 1, sizeof(struct page *),
+					  GFP_KERNEL);
+		if (!vdso32_pagelist)
+			goto alloc_failed;
 
-	for (i = 0; i < vdso32_pages; i++)
-		vdso32_pagelist[i] = virt_to_page(vdso32_kbase + i * PAGE_SIZE);
+		for (i = 0; i < vdso32_pages; i++)
+			vdso32_pagelist[i] = virt_to_page(vdso32_kbase + i * PAGE_SIZE);
 
-	vdso32_pagelist[i] = virt_to_page(vdso_data);
-#endif
+		vdso32_pagelist[i] = virt_to_page(vdso_data);
+	}
 
-#ifdef CONFIG_PPC64
-	vdso64_pagelist = kcalloc(vdso64_pages + 1, sizeof(struct page *),
-				  GFP_KERNEL);
-	if (!vdso64_pagelist)
-		goto alloc_failed;
+	if (IS_ENABLED(CONFIG_PPC64)) {
+		vdso64_pagelist = kcalloc(vdso64_pages + 1, sizeof(struct page *),
+					  GFP_KERNEL);
+		if (!vdso64_pagelist)
+			goto alloc_failed;
 
-	for (i = 0; i < vdso64_pages; i++)
-		vdso64_pagelist[i] = virt_to_page(vdso64_kbase + i * PAGE_SIZE);
+		for (i = 0; i < vdso64_pages; i++)
+			vdso64_pagelist[i] = virt_to_page(vdso64_kbase + i * PAGE_SIZE);
 
-	vdso64_pagelist[i] = virt_to_page(vdso_data);
-#endif /* CONFIG_PPC64 */
+		vdso64_pagelist[i] = virt_to_page(vdso_data);
+	}
 
 	smp_wmb();
 	vdso_ready = 1;
@@ -784,9 +772,8 @@ static int __init vdso_init(void)
 	pr_err("vDSO setup failure, not enabled !\n");
 alloc_failed:
 	vdso32_pages = 0;
-#ifdef CONFIG_PPC64
 	vdso64_pages = 0;
-#endif
+
 	return 0;
 }
 arch_initcall(vdso_init);
-- 
2.25.0


^ permalink raw reply related

* [PATCH v1 5/9] powerpc/vdso: move to _install_special_mapping() and remove arch_vma_name()
From: Christophe Leroy @ 2020-08-25 13:54 UTC (permalink / raw)
  To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman
  Cc: linuxppc-dev, linux-kernel
In-Reply-To: <df48ed76cf8a756a7f97ed42a1a39d0a404014bc.1598363608.git.christophe.leroy@csgroup.eu>

From commit 2fea7f6c98f5 ("arm64: vdso: move to
_install_special_mapping and remove arch_vma_name").

Use the new _install_special_mapping() API added by
commit a62c34bd2a8a ("x86, mm: Improve _install_special_mapping
and fix x86 vdso naming") which obsolete install_special_mapping().

And remove arch_vma_name() as the name is handled by the new API.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
 arch/powerpc/kernel/vdso.c | 59 +++++++++++++++++++-------------------
 1 file changed, 30 insertions(+), 29 deletions(-)

diff --git a/arch/powerpc/kernel/vdso.c b/arch/powerpc/kernel/vdso.c
index bbb69832fd46..4ccfc0dc96b5 100644
--- a/arch/powerpc/kernel/vdso.c
+++ b/arch/powerpc/kernel/vdso.c
@@ -47,7 +47,6 @@
 
 static unsigned int vdso32_pages;
 static void *vdso32_kbase;
-static struct page **vdso32_pagelist;
 unsigned long vdso32_sigtramp;
 unsigned long vdso32_rt_sigtramp;
 
@@ -56,7 +55,6 @@ extern char vdso32_start, vdso32_end;
 extern char vdso64_start, vdso64_end;
 static void *vdso64_kbase = &vdso64_start;
 static unsigned int vdso64_pages;
-static struct page **vdso64_pagelist;
 #ifdef CONFIG_PPC64
 unsigned long vdso64_rt_sigtramp;
 #endif /* CONFIG_PPC64 */
@@ -117,6 +115,14 @@ struct lib64_elfinfo
 };
 
 
+static struct vm_special_mapping vdso32_spec __ro_after_init = {
+	.name = "[vdso]",
+};
+
+static struct vm_special_mapping vdso64_spec __ro_after_init = {
+	.name = "[vdso]",
+};
+
 /*
  * This is called from binfmt_elf, we create the special vma for the
  * vDSO and insert it into the mm struct tree
@@ -124,7 +130,8 @@ struct lib64_elfinfo
 int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
 {
 	struct mm_struct *mm = current->mm;
-	struct page **vdso_pagelist;
+	struct vm_special_mapping *vdso_spec;
+	struct vm_area_struct *vma;
 	unsigned long vdso_pages;
 	unsigned long vdso_base;
 	int rc;
@@ -133,11 +140,11 @@ int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
 		return 0;
 
 	if (is_32bit_task()) {
-		vdso_pagelist = vdso32_pagelist;
+		vdso_spec = &vdso32_spec;
 		vdso_pages = vdso32_pages;
 		vdso_base = VDSO32_MBASE;
 	} else {
-		vdso_pagelist = vdso64_pagelist;
+		vdso_spec = &vdso64_spec;
 		vdso_pages = vdso64_pages;
 		/*
 		 * On 64bit we don't have a preferred map address. This
@@ -194,12 +201,12 @@ int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
 	 * It's fine to use that for setting breakpoints in the vDSO code
 	 * pages though.
 	 */
-	rc = install_special_mapping(mm, vdso_base, vdso_pages << PAGE_SHIFT,
-				     VM_READ|VM_EXEC|
-				     VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC,
-				     vdso_pagelist);
-	if (rc) {
+	vma = _install_special_mapping(mm, vdso_base, vdso_pages << PAGE_SHIFT,
+				       VM_READ | VM_EXEC | VM_MAYREAD |
+				       VM_MAYWRITE | VM_MAYEXEC, vdso_spec);
+	if (IS_ERR(vma)) {
 		current->mm->context.vdso_base = 0;
+		rc = PTR_ERR(vma);
 		goto fail_mmapsem;
 	}
 
@@ -211,15 +218,6 @@ int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
 	return rc;
 }
 
-const char *arch_vma_name(struct vm_area_struct *vma)
-{
-	if (vma->vm_mm && vma->vm_start == vma->vm_mm->context.vdso_base)
-		return "[vdso]";
-	return NULL;
-}
-
-
-
 #ifdef CONFIG_VDSO32
 static void * __init find_section32(Elf32_Ehdr *ehdr, const char *secname,
 				  unsigned long *size)
@@ -685,6 +683,7 @@ early_initcall(vdso_getcpu_init);
 static int __init vdso_init(void)
 {
 	int i;
+	struct page **pagelist;
 
 #ifdef CONFIG_PPC64
 	/*
@@ -740,27 +739,29 @@ static int __init vdso_init(void)
 
 	if (IS_ENABLED(CONFIG_VDSO32)) {
 		/* Make sure pages are in the correct state */
-		vdso32_pagelist = kcalloc(vdso32_pages + 1, sizeof(struct page *),
-					  GFP_KERNEL);
-		if (!vdso32_pagelist)
+		pagelist = kcalloc(vdso32_pages + 1, sizeof(struct page *), GFP_KERNEL);
+		if (!pagelist)
 			goto alloc_failed;
 
 		for (i = 0; i < vdso32_pages; i++)
-			vdso32_pagelist[i] = virt_to_page(vdso32_kbase + i * PAGE_SIZE);
+			pagelist[i] = virt_to_page(vdso32_kbase + i * PAGE_SIZE);
+
+		pagelist[i++] = virt_to_page(vdso_data);
 
-		vdso32_pagelist[i] = virt_to_page(vdso_data);
+		vdso32_spec.pages = pagelist;
 	}
 
 	if (IS_ENABLED(CONFIG_PPC64)) {
-		vdso64_pagelist = kcalloc(vdso64_pages + 1, sizeof(struct page *),
-					  GFP_KERNEL);
-		if (!vdso64_pagelist)
+		pagelist = kcalloc(vdso64_pages + 1, sizeof(struct page *), GFP_KERNEL);
+		if (!pagelist)
 			goto alloc_failed;
 
 		for (i = 0; i < vdso64_pages; i++)
-			vdso64_pagelist[i] = virt_to_page(vdso64_kbase + i * PAGE_SIZE);
+			pagelist[i] = virt_to_page(vdso64_kbase + i * PAGE_SIZE);
+
+		pagelist[i++] = virt_to_page(vdso_data);
 
-		vdso64_pagelist[i] = virt_to_page(vdso_data);
+		vdso64_spec.pages = pagelist;
 	}
 
 	smp_wmb();
-- 
2.25.0


^ permalink raw reply related

* [PATCH v1 9/9] powerpc/vdso: Remove unused \tmp param in __get_datapage()
From: Christophe Leroy @ 2020-08-25 13:54 UTC (permalink / raw)
  To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman
  Cc: linuxppc-dev, linux-kernel
In-Reply-To: <df48ed76cf8a756a7f97ed42a1a39d0a404014bc.1598363608.git.christophe.leroy@csgroup.eu>

The \tmp param is not used anymore, remove it.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
 arch/powerpc/include/asm/vdso/gettimeofday.h | 4 ++--
 arch/powerpc/include/asm/vdso_datapage.h     | 2 +-
 arch/powerpc/kernel/vdso32/cacheflush.S      | 2 +-
 arch/powerpc/kernel/vdso32/datapage.S        | 4 ++--
 arch/powerpc/kernel/vdso64/cacheflush.S      | 2 +-
 arch/powerpc/kernel/vdso64/datapage.S        | 4 ++--
 6 files changed, 9 insertions(+), 9 deletions(-)

diff --git a/arch/powerpc/include/asm/vdso/gettimeofday.h b/arch/powerpc/include/asm/vdso/gettimeofday.h
index 59a609a48b63..8602f1243e8d 100644
--- a/arch/powerpc/include/asm/vdso/gettimeofday.h
+++ b/arch/powerpc/include/asm/vdso/gettimeofday.h
@@ -22,7 +22,7 @@
 #ifdef CONFIG_PPC64
 	PPC_STL		r2, STACK_FRAME_OVERHEAD + STK_GOT(r1)
 #endif
-	get_datapage	r5, r0
+	get_datapage	r5
 	addi		r5, r5, VDSO_DATA_OFFSET
 	bl		\funct
 	PPC_LL		r0, STACK_FRAME_OVERHEAD + PPC_LR_STKOFF(r1)
@@ -51,7 +51,7 @@
 #ifdef CONFIG_PPC64
 	PPC_STL		r2, STACK_FRAME_OVERHEAD + STK_GOT(r1)
 #endif
-	get_datapage	r4, r0
+	get_datapage	r4
 	addi		r4, r4, VDSO_DATA_OFFSET
 	bl		\funct
 	PPC_LL		r0, STACK_FRAME_OVERHEAD + PPC_LR_STKOFF(r1)
diff --git a/arch/powerpc/include/asm/vdso_datapage.h b/arch/powerpc/include/asm/vdso_datapage.h
index 2bc415f7714c..71f44598f392 100644
--- a/arch/powerpc/include/asm/vdso_datapage.h
+++ b/arch/powerpc/include/asm/vdso_datapage.h
@@ -102,7 +102,7 @@ extern struct vdso_arch_data *vdso_data;
 
 #else /* __ASSEMBLY__ */
 
-.macro get_datapage ptr, tmp
+.macro get_datapage ptr
 	bcl	20, 31, .+4
 999:
 	mflr	\ptr
diff --git a/arch/powerpc/kernel/vdso32/cacheflush.S b/arch/powerpc/kernel/vdso32/cacheflush.S
index 3440ddf21c8b..017843bf5382 100644
--- a/arch/powerpc/kernel/vdso32/cacheflush.S
+++ b/arch/powerpc/kernel/vdso32/cacheflush.S
@@ -27,7 +27,7 @@ V_FUNCTION_BEGIN(__kernel_sync_dicache)
 #ifdef CONFIG_PPC64
 	mflr	r12
   .cfi_register lr,r12
-	get_datapage	r10, r0
+	get_datapage	r10
 	mtlr	r12
 #endif
 
diff --git a/arch/powerpc/kernel/vdso32/datapage.S b/arch/powerpc/kernel/vdso32/datapage.S
index 5513a4f8253e..0513a2eabec8 100644
--- a/arch/powerpc/kernel/vdso32/datapage.S
+++ b/arch/powerpc/kernel/vdso32/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, r0
+	get_datapage	r3
 	mtlr	r12
 	addi	r3,r3,CFG_SYSCALL_MAP32
 	beqlr
@@ -49,7 +49,7 @@ V_FUNCTION_BEGIN(__kernel_get_tbfreq)
   .cfi_startproc
 	mflr	r12
   .cfi_register lr,r12
-	get_datapage	r3, r0
+	get_datapage	r3
 	lwz	r4,(CFG_TB_TICKS_PER_SEC + 4)(r3)
 	lwz	r3,CFG_TB_TICKS_PER_SEC(r3)
 	mtlr	r12
diff --git a/arch/powerpc/kernel/vdso64/cacheflush.S b/arch/powerpc/kernel/vdso64/cacheflush.S
index cab14324242b..61985de5758f 100644
--- a/arch/powerpc/kernel/vdso64/cacheflush.S
+++ b/arch/powerpc/kernel/vdso64/cacheflush.S
@@ -25,7 +25,7 @@ V_FUNCTION_BEGIN(__kernel_sync_dicache)
   .cfi_startproc
 	mflr	r12
   .cfi_register lr,r12
-	get_datapage	r10, r0
+	get_datapage	r10
 	mtlr	r12
 
 	lwz	r7,CFG_DCACHE_BLOCKSZ(r10)
diff --git a/arch/powerpc/kernel/vdso64/datapage.S b/arch/powerpc/kernel/vdso64/datapage.S
index 03bb72c440dc..00760dc69d68 100644
--- a/arch/powerpc/kernel/vdso64/datapage.S
+++ b/arch/powerpc/kernel/vdso64/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, r0
+	get_datapage	r3
 	mtlr	r12
 	addi	r3,r3,CFG_SYSCALL_MAP64
 	cmpldi	cr0,r4,0
@@ -50,7 +50,7 @@ V_FUNCTION_BEGIN(__kernel_get_tbfreq)
   .cfi_startproc
 	mflr	r12
   .cfi_register lr,r12
-	get_datapage	r3, r0
+	get_datapage	r3
 	ld	r3,CFG_TB_TICKS_PER_SEC(r3)
 	mtlr	r12
 	crclr	cr0*4+so
-- 
2.25.0


^ permalink raw reply related

* [PATCH v1 7/9] powerpc/vdso: Move vdso datapage up front
From: Christophe Leroy @ 2020-08-25 13:54 UTC (permalink / raw)
  To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman
  Cc: linuxppc-dev, linux-kernel
In-Reply-To: <df48ed76cf8a756a7f97ed42a1a39d0a404014bc.1598363608.git.christophe.leroy@csgroup.eu>

Move the vdso datapage in front of the VDSO area,
before vdso test.

This will allow to remove the __kernel_datapage_offset symbol
and simplify __get_datapage() in the following patch.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
 arch/powerpc/include/asm/mmu_context.h |  4 +++-
 arch/powerpc/kernel/vdso.c             | 22 ++++++++++------------
 2 files changed, 13 insertions(+), 13 deletions(-)

diff --git a/arch/powerpc/include/asm/mmu_context.h b/arch/powerpc/include/asm/mmu_context.h
index 7f3658a97384..be18ad12bb54 100644
--- a/arch/powerpc/include/asm/mmu_context.h
+++ b/arch/powerpc/include/asm/mmu_context.h
@@ -262,7 +262,9 @@ extern void arch_exit_mmap(struct mm_struct *mm);
 static inline void arch_unmap(struct mm_struct *mm,
 			      unsigned long start, unsigned long end)
 {
-	if (start <= mm->context.vdso_base && mm->context.vdso_base < end)
+	unsigned long vdso_base = mm->context.vdso_base - PAGE_SIZE;
+
+	if (start <= vdso_base && vdso_base < end)
 		mm->context.vdso_base = 0;
 }
 
diff --git a/arch/powerpc/kernel/vdso.c b/arch/powerpc/kernel/vdso.c
index b9270923452e..1d72c4b7672f 100644
--- a/arch/powerpc/kernel/vdso.c
+++ b/arch/powerpc/kernel/vdso.c
@@ -124,7 +124,7 @@ static int vdso_mremap(unsigned long vdso_pages,
 	if (new_size != vdso_size)
 		return -EINVAL;
 
-	current->mm->context.vdso_base = (unsigned long)new_vma->vm_start;
+	current->mm->context.vdso_base = (unsigned long)new_vma->vm_start + PAGE_SIZE;
 
 	return 0;
 }
@@ -217,7 +217,7 @@ int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
 	 * install_special_mapping or the perf counter mmap tracking code
 	 * will fail to recognise it as a vDSO (since arch_vma_name fails).
 	 */
-	current->mm->context.vdso_base = vdso_base;
+	current->mm->context.vdso_base = vdso_base + PAGE_SIZE;
 
 	/*
 	 * our vma flags don't have VM_WRITE so by default, the process isn't
@@ -516,8 +516,7 @@ static __init int vdso_fixup_datapage(struct lib32_elfinfo *v32,
 		return -1;
 	}
 	*((int *)(vdso64_kbase + sym64->st_value - VDSO64_LBASE)) =
-		(vdso64_pages << PAGE_SHIFT) -
-		(sym64->st_value - VDSO64_LBASE);
+		(sym64->st_value - VDSO64_LBASE) - PAGE_SIZE;
 #endif /* CONFIG_PPC64 */
 
 #ifdef CONFIG_VDSO32
@@ -528,8 +527,7 @@ static __init int vdso_fixup_datapage(struct lib32_elfinfo *v32,
 		return -1;
 	}
 	*((int *)(vdso32_kbase + (sym32->st_value - VDSO32_LBASE))) =
-		(vdso32_pages << PAGE_SHIFT) -
-		(sym32->st_value - VDSO32_LBASE);
+		(sym32->st_value - VDSO32_LBASE) - PAGE_SIZE;
 #endif
 
 	return 0;
@@ -771,10 +769,10 @@ static int __init vdso_init(void)
 		if (!pagelist)
 			goto alloc_failed;
 
-		for (i = 0; i < vdso32_pages; i++)
-			pagelist[i] = virt_to_page(vdso32_kbase + i * PAGE_SIZE);
+		pagelist[0] = virt_to_page(vdso_data);
 
-		pagelist[i++] = virt_to_page(vdso_data);
+		for (i = 0; i < vdso32_pages; i++)
+			pagelist[i + 1] = virt_to_page(vdso32_kbase + i * PAGE_SIZE);
 
 		vdso32_spec.pages = pagelist;
 	}
@@ -784,10 +782,10 @@ static int __init vdso_init(void)
 		if (!pagelist)
 			goto alloc_failed;
 
-		for (i = 0; i < vdso64_pages; i++)
-			pagelist[i] = virt_to_page(vdso64_kbase + i * PAGE_SIZE);
+		pagelist[0] = virt_to_page(vdso_data);
 
-		pagelist[i++] = virt_to_page(vdso_data);
+		for (i = 0; i < vdso64_pages; i++)
+			pagelist[i + 1] = virt_to_page(vdso64_kbase + i * PAGE_SIZE);
 
 		vdso64_spec.pages = pagelist;
 	}
-- 
2.25.0


^ permalink raw reply related

* [PATCH v1 6/9] powerpc/vdso: Provide vdso_remap()
From: Christophe Leroy @ 2020-08-25 13:54 UTC (permalink / raw)
  To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman
  Cc: linuxppc-dev, linux-kernel
In-Reply-To: <df48ed76cf8a756a7f97ed42a1a39d0a404014bc.1598363608.git.christophe.leroy@csgroup.eu>

Provide vdso_remap() through _install_special_mapping() and
drop arch_remap().

This adds a test of the size and returns -EINVAL if the size
is not correct.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
 arch/powerpc/include/asm/mm-arch-hooks.h | 25 ---------------------
 arch/powerpc/kernel/vdso.c               | 28 ++++++++++++++++++++++++
 2 files changed, 28 insertions(+), 25 deletions(-)
 delete mode 100644 arch/powerpc/include/asm/mm-arch-hooks.h

diff --git a/arch/powerpc/include/asm/mm-arch-hooks.h b/arch/powerpc/include/asm/mm-arch-hooks.h
deleted file mode 100644
index dce274be824a..000000000000
--- a/arch/powerpc/include/asm/mm-arch-hooks.h
+++ /dev/null
@@ -1,25 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0-only */
-/*
- * Architecture specific mm hooks
- *
- * Copyright (C) 2015, IBM Corporation
- * Author: Laurent Dufour <ldufour@linux.vnet.ibm.com>
- */
-
-#ifndef _ASM_POWERPC_MM_ARCH_HOOKS_H
-#define _ASM_POWERPC_MM_ARCH_HOOKS_H
-
-static inline void arch_remap(struct mm_struct *mm,
-			      unsigned long old_start, unsigned long old_end,
-			      unsigned long new_start, unsigned long new_end)
-{
-	/*
-	 * mremap() doesn't allow moving multiple vmas so we can limit the
-	 * check to old_start == vdso_base.
-	 */
-	if (old_start == mm->context.vdso_base)
-		mm->context.vdso_base = new_start;
-}
-#define arch_remap arch_remap
-
-#endif /* _ASM_POWERPC_MM_ARCH_HOOKS_H */
diff --git a/arch/powerpc/kernel/vdso.c b/arch/powerpc/kernel/vdso.c
index 4ccfc0dc96b5..b9270923452e 100644
--- a/arch/powerpc/kernel/vdso.c
+++ b/arch/powerpc/kernel/vdso.c
@@ -114,13 +114,41 @@ struct lib64_elfinfo
 	unsigned long	text;
 };
 
+static int vdso_mremap(unsigned long vdso_pages,
+		       const struct vm_special_mapping *sm,
+		       struct vm_area_struct *new_vma)
+{
+	unsigned long new_size = new_vma->vm_end - new_vma->vm_start;
+	unsigned long vdso_size = (vdso_pages + 1) << PAGE_SHIFT;
+
+	if (new_size != vdso_size)
+		return -EINVAL;
+
+	current->mm->context.vdso_base = (unsigned long)new_vma->vm_start;
+
+	return 0;
+}
+
+static int vdso32_mremap(const struct vm_special_mapping *sm,
+			 struct vm_area_struct *new_vma)
+{
+	return vdso_mremap(vdso32_pages, sm, new_vma);
+}
+
+static int vdso64_mremap(const struct vm_special_mapping *sm,
+			 struct vm_area_struct *new_vma)
+{
+	return vdso_mremap(vdso64_pages, sm, new_vma);
+}
 
 static struct vm_special_mapping vdso32_spec __ro_after_init = {
 	.name = "[vdso]",
+	.mremap = vdso32_mremap,
 };
 
 static struct vm_special_mapping vdso64_spec __ro_after_init = {
 	.name = "[vdso]",
+	.mremap = vdso64_mremap,
 };
 
 /*
-- 
2.25.0


^ permalink raw reply related

* [PATCH v1 8/9] powerpc/vdso: Remove __kernel_datapage_offset and simplify __get_datapage()
From: Christophe Leroy @ 2020-08-25 13:54 UTC (permalink / raw)
  To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman
  Cc: linuxppc-dev, linux-kernel
In-Reply-To: <df48ed76cf8a756a7f97ed42a1a39d0a404014bc.1598363608.git.christophe.leroy@csgroup.eu>

The VDSO datapage and the text pages are always located immediately
next to each other, so it can be hardcoded without an indirection
through __kernel_datapage_offset

Before:
clock-getres-realtime-coarse:    vdso: 714 nsec/call
clock-gettime-realtime-coarse:    vdso: 792 nsec/call
clock-gettime-realtime:    vdso: 1243 nsec/call

After:
clock-getres-realtime-coarse:    vdso: 699 nsec/call
clock-gettime-realtime-coarse:    vdso: 784 nsec/call
clock-gettime-realtime:    vdso: 1231 nsec/call

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
 arch/powerpc/include/asm/vdso_datapage.h |  8 +++--
 arch/powerpc/kernel/vdso.c               | 37 ------------------------
 arch/powerpc/kernel/vdso32/datapage.S    |  3 --
 arch/powerpc/kernel/vdso32/vdso32.lds.S  |  7 ++---
 arch/powerpc/kernel/vdso64/datapage.S    |  3 --
 arch/powerpc/kernel/vdso64/vdso64.lds.S  |  7 ++---
 6 files changed, 9 insertions(+), 56 deletions(-)

diff --git a/arch/powerpc/include/asm/vdso_datapage.h b/arch/powerpc/include/asm/vdso_datapage.h
index c4d320504d26..2bc415f7714c 100644
--- a/arch/powerpc/include/asm/vdso_datapage.h
+++ b/arch/powerpc/include/asm/vdso_datapage.h
@@ -104,10 +104,12 @@ extern struct vdso_arch_data *vdso_data;
 
 .macro get_datapage ptr, tmp
 	bcl	20, 31, .+4
+999:
 	mflr	\ptr
-	addi	\ptr, \ptr, (__kernel_datapage_offset - (.-4))@l
-	lwz	\tmp, 0(\ptr)
-	add	\ptr, \tmp, \ptr
+#if CONFIG_PPC_PAGE_SHIFT > 14
+	addis	\ptr, \ptr, (_vdso_datapage - 999b)@ha
+#endif
+	addi	\ptr, \ptr, (_vdso_datapage - 999b)@l
 .endm
 
 #endif /* __ASSEMBLY__ */
diff --git a/arch/powerpc/kernel/vdso.c b/arch/powerpc/kernel/vdso.c
index 1d72c4b7672f..e2568d9ecdff 100644
--- a/arch/powerpc/kernel/vdso.c
+++ b/arch/powerpc/kernel/vdso.c
@@ -500,40 +500,6 @@ static __init void vdso_setup_trampolines(struct lib32_elfinfo *v32,
 	vdso32_rt_sigtramp = find_function32(v32, "__kernel_sigtramp_rt32");
 }
 
-static __init int vdso_fixup_datapage(struct lib32_elfinfo *v32,
-				       struct lib64_elfinfo *v64)
-{
-#ifdef CONFIG_VDSO32
-	Elf32_Sym *sym32;
-#endif
-#ifdef CONFIG_PPC64
-	Elf64_Sym *sym64;
-
-       	sym64 = find_symbol64(v64, "__kernel_datapage_offset");
-	if (sym64 == NULL) {
-		printk(KERN_ERR "vDSO64: Can't find symbol "
-		       "__kernel_datapage_offset !\n");
-		return -1;
-	}
-	*((int *)(vdso64_kbase + sym64->st_value - VDSO64_LBASE)) =
-		(sym64->st_value - VDSO64_LBASE) - PAGE_SIZE;
-#endif /* CONFIG_PPC64 */
-
-#ifdef CONFIG_VDSO32
-	sym32 = find_symbol32(v32, "__kernel_datapage_offset");
-	if (sym32 == NULL) {
-		printk(KERN_ERR "vDSO32: Can't find symbol "
-		       "__kernel_datapage_offset !\n");
-		return -1;
-	}
-	*((int *)(vdso32_kbase + (sym32->st_value - VDSO32_LBASE))) =
-		(sym32->st_value - VDSO32_LBASE) - PAGE_SIZE;
-#endif
-
-	return 0;
-}
-
-
 static __init int vdso_fixup_features(struct lib32_elfinfo *v32,
 				      struct lib64_elfinfo *v64)
 {
@@ -634,9 +600,6 @@ static __init int vdso_setup(void)
 	if (vdso_do_find_sections(&v32, &v64))
 		return -1;
 
-	if (vdso_fixup_datapage(&v32, &v64))
-		return -1;
-
 	if (vdso_fixup_features(&v32, &v64))
 		return -1;
 
diff --git a/arch/powerpc/kernel/vdso32/datapage.S b/arch/powerpc/kernel/vdso32/datapage.S
index 217bb630f8f9..5513a4f8253e 100644
--- a/arch/powerpc/kernel/vdso32/datapage.S
+++ b/arch/powerpc/kernel/vdso32/datapage.S
@@ -13,9 +13,6 @@
 #include <asm/vdso_datapage.h>
 
 	.text
-	.global	__kernel_datapage_offset;
-__kernel_datapage_offset:
-	.long	0
 
 /*
  * void *__kernel_get_syscall_map(unsigned int *syscall_count) ;
diff --git a/arch/powerpc/kernel/vdso32/vdso32.lds.S b/arch/powerpc/kernel/vdso32/vdso32.lds.S
index 582c5b046cc9..25be27b47a9f 100644
--- a/arch/powerpc/kernel/vdso32/vdso32.lds.S
+++ b/arch/powerpc/kernel/vdso32/vdso32.lds.S
@@ -4,6 +4,7 @@
  * library
  */
 #include <asm/vdso.h>
+#include <asm/page.h>
 
 #ifdef __LITTLE_ENDIAN__
 OUTPUT_FORMAT("elf32-powerpcle", "elf32-powerpcle", "elf32-powerpcle")
@@ -15,6 +16,7 @@ ENTRY(_start)
 
 SECTIONS
 {
+	PROVIDE(_vdso_datapage = . - PAGE_SIZE);
 	. = VDSO32_LBASE + SIZEOF_HEADERS;
 
 	.hash          	: { *(.hash) }			:text
@@ -139,11 +141,6 @@ VERSION
 {
 	VDSO_VERSION_STRING {
 	global:
-		/*
-		 * Has to be there for the kernel to find
-		 */
-		__kernel_datapage_offset;
-
 		__kernel_get_syscall_map;
 #ifndef CONFIG_PPC_BOOK3S_601
 		__kernel_gettimeofday;
diff --git a/arch/powerpc/kernel/vdso64/datapage.S b/arch/powerpc/kernel/vdso64/datapage.S
index 067247d3efb9..03bb72c440dc 100644
--- a/arch/powerpc/kernel/vdso64/datapage.S
+++ b/arch/powerpc/kernel/vdso64/datapage.S
@@ -13,9 +13,6 @@
 #include <asm/vdso_datapage.h>
 
 	.text
-.global	__kernel_datapage_offset;
-__kernel_datapage_offset:
-	.long	0
 
 /*
  * void *__kernel_get_syscall_map(unsigned int *syscall_count) ;
diff --git a/arch/powerpc/kernel/vdso64/vdso64.lds.S b/arch/powerpc/kernel/vdso64/vdso64.lds.S
index 4e3a8d4ee614..aaa5acf6d1b9 100644
--- a/arch/powerpc/kernel/vdso64/vdso64.lds.S
+++ b/arch/powerpc/kernel/vdso64/vdso64.lds.S
@@ -4,6 +4,7 @@
  * library
  */
 #include <asm/vdso.h>
+#include <asm/page.h>
 
 #ifdef __LITTLE_ENDIAN__
 OUTPUT_FORMAT("elf64-powerpcle", "elf64-powerpcle", "elf64-powerpcle")
@@ -15,6 +16,7 @@ ENTRY(_start)
 
 SECTIONS
 {
+	PROVIDE(_vdso_datapage = . - PAGE_SIZE);
 	. = VDSO64_LBASE + SIZEOF_HEADERS;
 
 	.hash		: { *(.hash) }			:text
@@ -139,11 +141,6 @@ VERSION
 {
 	VDSO_VERSION_STRING {
 	global:
-		/*
-		 * Has to be there for the kernel to find
-		 */
-		__kernel_datapage_offset;
-
 		__kernel_get_syscall_map;
 		__kernel_gettimeofday;
 		__kernel_clock_gettime;
-- 
2.25.0


^ permalink raw reply related

* Re: [PATCH v8 2/8] powerpc/vdso: Remove __kernel_datapage_offset and simplify __get_datapage()
From: Christophe Leroy @ 2020-08-25 14:15 UTC (permalink / raw)
  To: Michael Ellerman, Benjamin Herrenschmidt, Paul Mackerras, nathanl
  Cc: linux-arch, arnd, linux-kernel, luto, tglx, vincenzo.frascino,
	linuxppc-dev
In-Reply-To: <2f9b7d02-9e2f-4724-2608-c5573f6507a2@csgroup.eu>



Le 04/08/2020 à 13:17, Christophe Leroy a écrit :
> 
> 
> On 07/16/2020 02:59 AM, Michael Ellerman wrote:
>> Christophe Leroy <christophe.leroy@c-s.fr> writes:
>>> The VDSO datapage and the text pages are always located immediately
>>> next to each other, so it can be hardcoded without an indirection
>>> through __kernel_datapage_offset
>>>
>>> In order to ease things, move the data page in front like other
>>> arches, that way there is no need to know the size of the library
>>> to locate the data page.
>>>
[...]

>>
>> I merged this but then realised it breaks the display of the vdso in 
>> /proc/self/maps.
>>
>> ie. the vdso vma gets no name:
>>
>>    # cat /proc/self/maps

[...]

>>
>>
>> And it's also going to break the logic in arch_unmap() to detect if
>> we're unmapping (part of) the VDSO. And it will break arch_remap() too.
>>
>> And the logic to recognise the signal trampoline in
>> arch/powerpc/perf/callchain_*.c as well.
> 
> I don't think it breaks that one, because ->vdsobase is still the start 
> of text.
> 
>>
>> So I'm going to rebase and drop this for now.
>>
>> Basically we have a bunch of places that assume that vdso_base is == the
>> start of the VDSO vma, and also that the code starts there. So that will
>> need some work to tease out all those assumptions and make them work
>> with this change.
> 
> Ok, one day I need to look at it in more details and see how other 
> architectures handle it etc ...
> 

I just sent out a series which switches powerpc to the new 
_install_special_mapping() API, the one powerpc uses being deprecated 
since commit a62c34bd2a8a ("x86, mm: Improve _install_special_mapping
and fix x86 vdso naming")

arch_remap() gets replaced by vdso_remap()

For arch_unmap(), I'm wondering how/what other architectures do, because 
powerpc seems to be the only one to erase the vdso context pointer when 
unmapping the vdso. So far I updated it to take into account the pages 
switch.

Everything else is not impacted because our vdso_base is still the base 
of the text and that's what those things (signal trampoline, callchain, 
...) expect.

Maybe we should change it to 'void *vdso' in the same way as other 
architectures, as it is not anymore the exact vdso_base but the start of 
VDSO text.

Note that the series applies on top of the generic C VDSO implementation 
series. However all but the last commit cleanly apply without that 
series. As that last commit is just an afterwork cleanup, it can come in 
a second step.

Christophe

^ permalink raw reply

* Re: [PATCH 17/29] fs_enet: Avoid comma separated statements
From: David Miller @ 2020-08-25 14:55 UTC (permalink / raw)
  To: joe; +Cc: trivial, netdev, linux-kernel, kuba, linuxppc-dev
In-Reply-To: <418850ae2026b293ea6ba3b8b19b8a7f8dfcaf3d.1598331149.git.joe@perches.com>

From: Joe Perches <joe@perches.com>
Date: Mon, 24 Aug 2020 21:56:14 -0700

> Use semicolons and braces.
> 
> Signed-off-by: Joe Perches <joe@perches.com>

Applied.

^ permalink raw reply

* [PATCH v7 00/12] huge vmalloc mappings
From: Nicholas Piggin @ 2020-08-25 14:57 UTC (permalink / raw)
  To: linux-mm, Andrew Morton
  Cc: linux-arch, linux-kernel, Nicholas Piggin, Christoph Hellwig,
	Zefan Li, Jonathan Cameron, linuxppc-dev

I think it's ready to go into -mm if it gets acks for the arch
changes.

Thanks,
Nick

Since v6:
- Fixed a false positive warning introduced in patch 2, found by
  kbuild test robot.

Since v5:
- Split arch changes out better and make the constant folding work
- Avoid most of the 80 column wrap, fix a reference to lib/ioremap.c
- Fix compile error on some archs

Since v4:
- Fixed an off-by-page-order bug in v4
- Several minor cleanups.
- Added page order to /proc/vmallocinfo
- Added hugepage to alloc_large_system_hage output.
- Made an architecture config option, powerpc only for now.

Since v3:
- Fixed an off-by-one bug in a loop
- Fix !CONFIG_HAVE_ARCH_HUGE_VMAP build fail
- Hopefully this time fix the arm64 vmap stack bug, thanks Jonathan
  Cameron for debugging the cause of this (hopefully).

Since v2:
- Rebased on vmalloc cleanups, split series into simpler pieces.
- Fixed several compile errors and warnings
- Keep the page array and accounting in small page units because
  struct vm_struct is an interface (this should fix x86 vmap stack debug
  assert). [Thanks Zefan]


Nicholas Piggin (12):
  mm/vmalloc: fix vmalloc_to_page for huge vmap mappings
  mm: apply_to_pte_range warn and fail if a large pte is encountered
  mm/vmalloc: rename vmap_*_range vmap_pages_*_range
  mm/ioremap: rename ioremap_*_range to vmap_*_range
  mm: HUGE_VMAP arch support cleanup
  powerpc: inline huge vmap supported functions
  arm64: inline huge vmap supported functions
  x86: inline huge vmap supported functions
  mm: Move vmap_range from mm/ioremap.c to mm/vmalloc.c
  mm/vmalloc: add vmap_range_noflush variant
  mm/vmalloc: Hugepage vmalloc mappings
  powerpc/64s/radix: Enable huge vmalloc mappings

 .../admin-guide/kernel-parameters.txt         |   2 +
 arch/Kconfig                                  |   4 +
 arch/arm64/include/asm/vmalloc.h              |  25 +
 arch/arm64/mm/mmu.c                           |  26 -
 arch/powerpc/Kconfig                          |   1 +
 arch/powerpc/include/asm/vmalloc.h            |  21 +
 arch/powerpc/mm/book3s64/radix_pgtable.c      |  21 -
 arch/x86/include/asm/vmalloc.h                |  23 +
 arch/x86/mm/ioremap.c                         |  19 -
 arch/x86/mm/pgtable.c                         |  13 -
 include/linux/io.h                            |   9 -
 include/linux/vmalloc.h                       |  10 +
 init/main.c                                   |   1 -
 mm/ioremap.c                                  | 225 +--------
 mm/memory.c                                   |  60 ++-
 mm/page_alloc.c                               |   5 +-
 mm/vmalloc.c                                  | 443 +++++++++++++++---
 17 files changed, 515 insertions(+), 393 deletions(-)

-- 
2.23.0


^ permalink raw reply

* [PATCH v7 01/12] mm/vmalloc: fix vmalloc_to_page for huge vmap mappings
From: Nicholas Piggin @ 2020-08-25 14:57 UTC (permalink / raw)
  To: linux-mm, Andrew Morton
  Cc: linux-arch, linux-kernel, Nicholas Piggin, Christoph Hellwig,
	Zefan Li, Jonathan Cameron, linuxppc-dev
In-Reply-To: <20200825145753.529284-1-npiggin@gmail.com>

vmalloc_to_page returns NULL for addresses mapped by larger pages[*].
Whether or not a vmap is huge depends on the architecture details,
alignments, boot options, etc., which the caller can not be expected
to know. Therefore HUGE_VMAP is a regression for vmalloc_to_page.

This change teaches vmalloc_to_page about larger pages, and returns
the struct page that corresponds to the offset within the large page.
This makes the API agnostic to mapping implementation details.

[*] As explained by commit 029c54b095995 ("mm/vmalloc.c: huge-vmap:
    fail gracefully on unexpected huge vmap mappings")

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
---
 mm/vmalloc.c | 41 ++++++++++++++++++++++++++---------------
 1 file changed, 26 insertions(+), 15 deletions(-)

diff --git a/mm/vmalloc.c b/mm/vmalloc.c
index b482d240f9a2..4e9b21adc73d 100644
--- a/mm/vmalloc.c
+++ b/mm/vmalloc.c
@@ -36,7 +36,7 @@
 #include <linux/bitops.h>
 #include <linux/rbtree_augmented.h>
 #include <linux/overflow.h>
-
+#include <linux/pgtable.h>
 #include <linux/uaccess.h>
 #include <asm/tlbflush.h>
 #include <asm/shmparam.h>
@@ -343,7 +343,9 @@ int is_vmalloc_or_module_addr(const void *x)
 }
 
 /*
- * Walk a vmap address to the struct page it maps.
+ * Walk a vmap address to the struct page it maps. Huge vmap mappings will
+ * return the tail page that corresponds to the base page address, which
+ * matches small vmap mappings.
  */
 struct page *vmalloc_to_page(const void *vmalloc_addr)
 {
@@ -363,25 +365,33 @@ struct page *vmalloc_to_page(const void *vmalloc_addr)
 
 	if (pgd_none(*pgd))
 		return NULL;
+	if (WARN_ON_ONCE(pgd_leaf(*pgd)))
+		return NULL; /* XXX: no allowance for huge pgd */
+	if (WARN_ON_ONCE(pgd_bad(*pgd)))
+		return NULL;
+
 	p4d = p4d_offset(pgd, addr);
 	if (p4d_none(*p4d))
 		return NULL;
-	pud = pud_offset(p4d, addr);
+	if (p4d_leaf(*p4d))
+		return p4d_page(*p4d) + ((addr & ~P4D_MASK) >> PAGE_SHIFT);
+	if (WARN_ON_ONCE(p4d_bad(*p4d)))
+		return NULL;
 
-	/*
-	 * Don't dereference bad PUD or PMD (below) entries. This will also
-	 * identify huge mappings, which we may encounter on architectures
-	 * that define CONFIG_HAVE_ARCH_HUGE_VMAP=y. Such regions will be
-	 * identified as vmalloc addresses by is_vmalloc_addr(), but are
-	 * not [unambiguously] associated with a struct page, so there is
-	 * no correct value to return for them.
-	 */
-	WARN_ON_ONCE(pud_bad(*pud));
-	if (pud_none(*pud) || pud_bad(*pud))
+	pud = pud_offset(p4d, addr);
+	if (pud_none(*pud))
+		return NULL;
+	if (pud_leaf(*pud))
+		return pud_page(*pud) + ((addr & ~PUD_MASK) >> PAGE_SHIFT);
+	if (WARN_ON_ONCE(pud_bad(*pud)))
 		return NULL;
+
 	pmd = pmd_offset(pud, addr);
-	WARN_ON_ONCE(pmd_bad(*pmd));
-	if (pmd_none(*pmd) || pmd_bad(*pmd))
+	if (pmd_none(*pmd))
+		return NULL;
+	if (pmd_leaf(*pmd))
+		return pmd_page(*pmd) + ((addr & ~PMD_MASK) >> PAGE_SHIFT);
+	if (WARN_ON_ONCE(pmd_bad(*pmd)))
 		return NULL;
 
 	ptep = pte_offset_map(pmd, addr);
@@ -389,6 +399,7 @@ struct page *vmalloc_to_page(const void *vmalloc_addr)
 	if (pte_present(pte))
 		page = pte_page(pte);
 	pte_unmap(ptep);
+
 	return page;
 }
 EXPORT_SYMBOL(vmalloc_to_page);
-- 
2.23.0


^ permalink raw reply related

* [PATCH v7 02/12] mm: apply_to_pte_range warn and fail if a large pte is encountered
From: Nicholas Piggin @ 2020-08-25 14:57 UTC (permalink / raw)
  To: linux-mm, Andrew Morton
  Cc: linux-arch, linux-kernel, Nicholas Piggin, Christoph Hellwig,
	Zefan Li, Jonathan Cameron, linuxppc-dev
In-Reply-To: <20200825145753.529284-1-npiggin@gmail.com>

apply_to_pte_range might mistake a large pte for bad, or treat it as a
page table, resulting in a crash or corruption. Add a test to warn and
return error if large entries are found.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
---
 mm/memory.c | 60 +++++++++++++++++++++++++++++++++++++++--------------
 1 file changed, 44 insertions(+), 16 deletions(-)

diff --git a/mm/memory.c b/mm/memory.c
index 602f4283122f..995b2e790b79 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -2262,13 +2262,20 @@ static int apply_to_pmd_range(struct mm_struct *mm, pud_t *pud,
 	}
 	do {
 		next = pmd_addr_end(addr, end);
-		if (create || !pmd_none_or_clear_bad(pmd)) {
-			err = apply_to_pte_range(mm, pmd, addr, next, fn, data,
-						 create);
-			if (err)
-				break;
+		if (pmd_none(*pmd) && !create)
+			continue;
+		if (WARN_ON_ONCE(pmd_leaf(*pmd)))
+			return -EINVAL;
+		if (!pmd_none(*pmd) && WARN_ON_ONCE(pmd_bad(*pmd))) {
+			if (!create)
+				continue;
+			pmd_clear_bad(pmd);
 		}
+		err = apply_to_pte_range(mm, pmd, addr, next, fn, data, create);
+		if (err)
+			break;
 	} while (pmd++, addr = next, addr != end);
+
 	return err;
 }
 
@@ -2289,13 +2296,20 @@ static int apply_to_pud_range(struct mm_struct *mm, p4d_t *p4d,
 	}
 	do {
 		next = pud_addr_end(addr, end);
-		if (create || !pud_none_or_clear_bad(pud)) {
-			err = apply_to_pmd_range(mm, pud, addr, next, fn, data,
-						 create);
-			if (err)
-				break;
+		if (pud_none(*pud) && !create)
+			continue;
+		if (WARN_ON_ONCE(pud_leaf(*pud)))
+			return -EINVAL;
+		if (!pud_none(*pud) && WARN_ON_ONCE(pud_bad(*pud))) {
+			if (!create)
+				continue;
+			pud_clear_bad(pud);
 		}
+		err = apply_to_pmd_range(mm, pud, addr, next, fn, data, create);
+		if (err)
+			break;
 	} while (pud++, addr = next, addr != end);
+
 	return err;
 }
 
@@ -2316,13 +2330,20 @@ static int apply_to_p4d_range(struct mm_struct *mm, pgd_t *pgd,
 	}
 	do {
 		next = p4d_addr_end(addr, end);
-		if (create || !p4d_none_or_clear_bad(p4d)) {
-			err = apply_to_pud_range(mm, p4d, addr, next, fn, data,
-						 create);
-			if (err)
-				break;
+		if (p4d_none(*p4d) && !create)
+			continue;
+		if (WARN_ON_ONCE(p4d_leaf(*p4d)))
+			return -EINVAL;
+		if (!p4d_none(*p4d) && WARN_ON_ONCE(p4d_bad(*p4d))) {
+			if (!create)
+				continue;
+			p4d_clear_bad(p4d);
 		}
+		err = apply_to_pud_range(mm, p4d, addr, next, fn, data, create);
+		if (err)
+			break;
 	} while (p4d++, addr = next, addr != end);
+
 	return err;
 }
 
@@ -2341,8 +2362,15 @@ static int __apply_to_page_range(struct mm_struct *mm, unsigned long addr,
 	pgd = pgd_offset(mm, addr);
 	do {
 		next = pgd_addr_end(addr, end);
-		if (!create && pgd_none_or_clear_bad(pgd))
+		if (pgd_none(*pgd) && !create)
 			continue;
+		if (WARN_ON_ONCE(pgd_leaf(*pgd)))
+			return -EINVAL;
+		if (!pgd_none(*pgd) && WARN_ON_ONCE(pgd_bad(*pgd))) {
+			if (!create)
+				continue;
+			pgd_clear_bad(pgd);
+		}
 		err = apply_to_p4d_range(mm, pgd, addr, next, fn, data, create);
 		if (err)
 			break;
-- 
2.23.0


^ permalink raw reply related

* [PATCH v7 03/12] mm/vmalloc: rename vmap_*_range vmap_pages_*_range
From: Nicholas Piggin @ 2020-08-25 14:57 UTC (permalink / raw)
  To: linux-mm, Andrew Morton
  Cc: linux-arch, linux-kernel, Nicholas Piggin, Christoph Hellwig,
	Zefan Li, Jonathan Cameron, linuxppc-dev
In-Reply-To: <20200825145753.529284-1-npiggin@gmail.com>

The vmalloc mapper operates on a struct page * array rather than a
linear physical address, re-name it to make this distinction clear.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
---
 mm/vmalloc.c | 16 ++++++++--------
 1 file changed, 8 insertions(+), 8 deletions(-)

diff --git a/mm/vmalloc.c b/mm/vmalloc.c
index 4e9b21adc73d..45cd80ec7eeb 100644
--- a/mm/vmalloc.c
+++ b/mm/vmalloc.c
@@ -189,7 +189,7 @@ void unmap_kernel_range_noflush(unsigned long start, unsigned long size)
 		arch_sync_kernel_mappings(start, end);
 }
 
-static int vmap_pte_range(pmd_t *pmd, unsigned long addr,
+static int vmap_pages_pte_range(pmd_t *pmd, unsigned long addr,
 		unsigned long end, pgprot_t prot, struct page **pages, int *nr,
 		pgtbl_mod_mask *mask)
 {
@@ -217,7 +217,7 @@ static int vmap_pte_range(pmd_t *pmd, unsigned long addr,
 	return 0;
 }
 
-static int vmap_pmd_range(pud_t *pud, unsigned long addr,
+static int vmap_pages_pmd_range(pud_t *pud, unsigned long addr,
 		unsigned long end, pgprot_t prot, struct page **pages, int *nr,
 		pgtbl_mod_mask *mask)
 {
@@ -229,13 +229,13 @@ static int vmap_pmd_range(pud_t *pud, unsigned long addr,
 		return -ENOMEM;
 	do {
 		next = pmd_addr_end(addr, end);
-		if (vmap_pte_range(pmd, addr, next, prot, pages, nr, mask))
+		if (vmap_pages_pte_range(pmd, addr, next, prot, pages, nr, mask))
 			return -ENOMEM;
 	} while (pmd++, addr = next, addr != end);
 	return 0;
 }
 
-static int vmap_pud_range(p4d_t *p4d, unsigned long addr,
+static int vmap_pages_pud_range(p4d_t *p4d, unsigned long addr,
 		unsigned long end, pgprot_t prot, struct page **pages, int *nr,
 		pgtbl_mod_mask *mask)
 {
@@ -247,13 +247,13 @@ static int vmap_pud_range(p4d_t *p4d, unsigned long addr,
 		return -ENOMEM;
 	do {
 		next = pud_addr_end(addr, end);
-		if (vmap_pmd_range(pud, addr, next, prot, pages, nr, mask))
+		if (vmap_pages_pmd_range(pud, addr, next, prot, pages, nr, mask))
 			return -ENOMEM;
 	} while (pud++, addr = next, addr != end);
 	return 0;
 }
 
-static int vmap_p4d_range(pgd_t *pgd, unsigned long addr,
+static int vmap_pages_p4d_range(pgd_t *pgd, unsigned long addr,
 		unsigned long end, pgprot_t prot, struct page **pages, int *nr,
 		pgtbl_mod_mask *mask)
 {
@@ -265,7 +265,7 @@ static int vmap_p4d_range(pgd_t *pgd, unsigned long addr,
 		return -ENOMEM;
 	do {
 		next = p4d_addr_end(addr, end);
-		if (vmap_pud_range(p4d, addr, next, prot, pages, nr, mask))
+		if (vmap_pages_pud_range(p4d, addr, next, prot, pages, nr, mask))
 			return -ENOMEM;
 	} while (p4d++, addr = next, addr != end);
 	return 0;
@@ -306,7 +306,7 @@ int map_kernel_range_noflush(unsigned long addr, unsigned long size,
 		next = pgd_addr_end(addr, end);
 		if (pgd_bad(*pgd))
 			mask |= PGTBL_PGD_MODIFIED;
-		err = vmap_p4d_range(pgd, addr, next, prot, pages, &nr, &mask);
+		err = vmap_pages_p4d_range(pgd, addr, next, prot, pages, &nr, &mask);
 		if (err)
 			return err;
 	} while (pgd++, addr = next, addr != end);
-- 
2.23.0


^ permalink raw reply related

* [PATCH v7 04/12] mm/ioremap: rename ioremap_*_range to vmap_*_range
From: Nicholas Piggin @ 2020-08-25 14:57 UTC (permalink / raw)
  To: linux-mm, Andrew Morton
  Cc: linux-arch, linux-kernel, Nicholas Piggin, Christoph Hellwig,
	Zefan Li, Jonathan Cameron, linuxppc-dev
In-Reply-To: <20200825145753.529284-1-npiggin@gmail.com>

This will be used as a generic kernel virtual mapping function, so
re-name it in preparation.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
---
 mm/ioremap.c | 64 +++++++++++++++++++++++++++-------------------------
 1 file changed, 33 insertions(+), 31 deletions(-)

diff --git a/mm/ioremap.c b/mm/ioremap.c
index 5fa1ab41d152..3f4d36f9745a 100644
--- a/mm/ioremap.c
+++ b/mm/ioremap.c
@@ -61,9 +61,9 @@ static inline int ioremap_pud_enabled(void) { return 0; }
 static inline int ioremap_pmd_enabled(void) { return 0; }
 #endif	/* CONFIG_HAVE_ARCH_HUGE_VMAP */
 
-static int ioremap_pte_range(pmd_t *pmd, unsigned long addr,
-		unsigned long end, phys_addr_t phys_addr, pgprot_t prot,
-		pgtbl_mod_mask *mask)
+static int vmap_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end,
+			phys_addr_t phys_addr, pgprot_t prot,
+			pgtbl_mod_mask *mask)
 {
 	pte_t *pte;
 	u64 pfn;
@@ -81,9 +81,8 @@ static int ioremap_pte_range(pmd_t *pmd, unsigned long addr,
 	return 0;
 }
 
-static int ioremap_try_huge_pmd(pmd_t *pmd, unsigned long addr,
-				unsigned long end, phys_addr_t phys_addr,
-				pgprot_t prot)
+static int vmap_try_huge_pmd(pmd_t *pmd, unsigned long addr, unsigned long end,
+			phys_addr_t phys_addr, pgprot_t prot)
 {
 	if (!ioremap_pmd_enabled())
 		return 0;
@@ -103,9 +102,9 @@ static int ioremap_try_huge_pmd(pmd_t *pmd, unsigned long addr,
 	return pmd_set_huge(pmd, phys_addr, prot);
 }
 
-static inline int ioremap_pmd_range(pud_t *pud, unsigned long addr,
-		unsigned long end, phys_addr_t phys_addr, pgprot_t prot,
-		pgtbl_mod_mask *mask)
+static int vmap_pmd_range(pud_t *pud, unsigned long addr, unsigned long end,
+			phys_addr_t phys_addr, pgprot_t prot,
+			pgtbl_mod_mask *mask)
 {
 	pmd_t *pmd;
 	unsigned long next;
@@ -116,20 +115,19 @@ static inline int ioremap_pmd_range(pud_t *pud, unsigned long addr,
 	do {
 		next = pmd_addr_end(addr, end);
 
-		if (ioremap_try_huge_pmd(pmd, addr, next, phys_addr, prot)) {
+		if (vmap_try_huge_pmd(pmd, addr, next, phys_addr, prot)) {
 			*mask |= PGTBL_PMD_MODIFIED;
 			continue;
 		}
 
-		if (ioremap_pte_range(pmd, addr, next, phys_addr, prot, mask))
+		if (vmap_pte_range(pmd, addr, next, phys_addr, prot, mask))
 			return -ENOMEM;
 	} while (pmd++, phys_addr += (next - addr), addr = next, addr != end);
 	return 0;
 }
 
-static int ioremap_try_huge_pud(pud_t *pud, unsigned long addr,
-				unsigned long end, phys_addr_t phys_addr,
-				pgprot_t prot)
+static int vmap_try_huge_pud(pud_t *pud, unsigned long addr, unsigned long end,
+			phys_addr_t phys_addr, pgprot_t prot)
 {
 	if (!ioremap_pud_enabled())
 		return 0;
@@ -149,9 +147,9 @@ static int ioremap_try_huge_pud(pud_t *pud, unsigned long addr,
 	return pud_set_huge(pud, phys_addr, prot);
 }
 
-static inline int ioremap_pud_range(p4d_t *p4d, unsigned long addr,
-		unsigned long end, phys_addr_t phys_addr, pgprot_t prot,
-		pgtbl_mod_mask *mask)
+static int vmap_pud_range(p4d_t *p4d, unsigned long addr, unsigned long end,
+			phys_addr_t phys_addr, pgprot_t prot,
+			pgtbl_mod_mask *mask)
 {
 	pud_t *pud;
 	unsigned long next;
@@ -162,20 +160,19 @@ static inline int ioremap_pud_range(p4d_t *p4d, unsigned long addr,
 	do {
 		next = pud_addr_end(addr, end);
 
-		if (ioremap_try_huge_pud(pud, addr, next, phys_addr, prot)) {
+		if (vmap_try_huge_pud(pud, addr, next, phys_addr, prot)) {
 			*mask |= PGTBL_PUD_MODIFIED;
 			continue;
 		}
 
-		if (ioremap_pmd_range(pud, addr, next, phys_addr, prot, mask))
+		if (vmap_pmd_range(pud, addr, next, phys_addr, prot, mask))
 			return -ENOMEM;
 	} while (pud++, phys_addr += (next - addr), addr = next, addr != end);
 	return 0;
 }
 
-static int ioremap_try_huge_p4d(p4d_t *p4d, unsigned long addr,
-				unsigned long end, phys_addr_t phys_addr,
-				pgprot_t prot)
+static int vmap_try_huge_p4d(p4d_t *p4d, unsigned long addr, unsigned long end,
+			phys_addr_t phys_addr, pgprot_t prot)
 {
 	if (!ioremap_p4d_enabled())
 		return 0;
@@ -195,9 +192,9 @@ static int ioremap_try_huge_p4d(p4d_t *p4d, unsigned long addr,
 	return p4d_set_huge(p4d, phys_addr, prot);
 }
 
-static inline int ioremap_p4d_range(pgd_t *pgd, unsigned long addr,
-		unsigned long end, phys_addr_t phys_addr, pgprot_t prot,
-		pgtbl_mod_mask *mask)
+static int vmap_p4d_range(pgd_t *pgd, unsigned long addr, unsigned long end,
+			phys_addr_t phys_addr, pgprot_t prot,
+			pgtbl_mod_mask *mask)
 {
 	p4d_t *p4d;
 	unsigned long next;
@@ -208,19 +205,19 @@ static inline int ioremap_p4d_range(pgd_t *pgd, unsigned long addr,
 	do {
 		next = p4d_addr_end(addr, end);
 
-		if (ioremap_try_huge_p4d(p4d, addr, next, phys_addr, prot)) {
+		if (vmap_try_huge_p4d(p4d, addr, next, phys_addr, prot)) {
 			*mask |= PGTBL_P4D_MODIFIED;
 			continue;
 		}
 
-		if (ioremap_pud_range(p4d, addr, next, phys_addr, prot, mask))
+		if (vmap_pud_range(p4d, addr, next, phys_addr, prot, mask))
 			return -ENOMEM;
 	} while (p4d++, phys_addr += (next - addr), addr = next, addr != end);
 	return 0;
 }
 
-int ioremap_page_range(unsigned long addr,
-		       unsigned long end, phys_addr_t phys_addr, pgprot_t prot)
+static int vmap_range(unsigned long addr, unsigned long end,
+			phys_addr_t phys_addr, pgprot_t prot)
 {
 	pgd_t *pgd;
 	unsigned long start;
@@ -235,8 +232,7 @@ int ioremap_page_range(unsigned long addr,
 	pgd = pgd_offset_k(addr);
 	do {
 		next = pgd_addr_end(addr, end);
-		err = ioremap_p4d_range(pgd, addr, next, phys_addr, prot,
-					&mask);
+		err = vmap_p4d_range(pgd, addr, next, phys_addr, prot, &mask);
 		if (err)
 			break;
 	} while (pgd++, phys_addr += (next - addr), addr = next, addr != end);
@@ -249,6 +245,12 @@ int ioremap_page_range(unsigned long addr,
 	return err;
 }
 
+int ioremap_page_range(unsigned long addr,
+		       unsigned long end, phys_addr_t phys_addr, pgprot_t prot)
+{
+	return vmap_range(addr, end, phys_addr, prot);
+}
+
 #ifdef CONFIG_GENERIC_IOREMAP
 void __iomem *ioremap_prot(phys_addr_t addr, size_t size, unsigned long prot)
 {
-- 
2.23.0


^ permalink raw reply related

* [PATCH v7 05/12] mm: HUGE_VMAP arch support cleanup
From: Nicholas Piggin @ 2020-08-25 14:57 UTC (permalink / raw)
  To: linux-mm, Andrew Morton
  Cc: linux-arch, H. Peter Anvin, Will Deacon, Catalin Marinas, x86,
	linux-kernel, Nicholas Piggin, Christoph Hellwig, Zefan Li,
	Borislav Petkov, Jonathan Cameron, Thomas Gleixner, linuxppc-dev,
	Ingo Molnar, linux-arm-kernel
In-Reply-To: <20200825145753.529284-1-npiggin@gmail.com>

This changes the awkward approach where architectures provide init
functions to determine which levels they can provide large mappings for,
to one where the arch is queried for each call.

This removes code and indirection, and allows constant-folding of dead
code for unsupported levels.

This also adds a prot argument to the arch query. This is unused
currently but could help with some architectures (e.g., some powerpc
processors can't map uncacheable memory with large pages).

Cc: linuxppc-dev@lists.ozlabs.org
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: linux-arm-kernel@lists.infradead.org
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: x86@kernel.org
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
---

Ack or objection from arch maintainers if this goes via the -mm tree?

 arch/arm64/include/asm/vmalloc.h         |  8 +++
 arch/arm64/mm/mmu.c                      | 10 +--
 arch/powerpc/include/asm/vmalloc.h       |  8 +++
 arch/powerpc/mm/book3s64/radix_pgtable.c |  8 +--
 arch/x86/include/asm/vmalloc.h           |  7 ++
 arch/x86/mm/ioremap.c                    | 10 +--
 include/linux/io.h                       |  9 ---
 include/linux/vmalloc.h                  |  6 ++
 init/main.c                              |  1 -
 mm/ioremap.c                             | 88 +++++++++---------------
 10 files changed, 77 insertions(+), 78 deletions(-)

diff --git a/arch/arm64/include/asm/vmalloc.h b/arch/arm64/include/asm/vmalloc.h
index 2ca708ab9b20..597b40405319 100644
--- a/arch/arm64/include/asm/vmalloc.h
+++ b/arch/arm64/include/asm/vmalloc.h
@@ -1,4 +1,12 @@
 #ifndef _ASM_ARM64_VMALLOC_H
 #define _ASM_ARM64_VMALLOC_H
 
+#include <asm/page.h>
+
+#ifdef CONFIG_HAVE_ARCH_HUGE_VMAP
+bool arch_vmap_p4d_supported(pgprot_t prot);
+bool arch_vmap_pud_supported(pgprot_t prot);
+bool arch_vmap_pmd_supported(pgprot_t prot);
+#endif
+
 #endif /* _ASM_ARM64_VMALLOC_H */
diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c
index 75df62fea1b6..9df7e0058c78 100644
--- a/arch/arm64/mm/mmu.c
+++ b/arch/arm64/mm/mmu.c
@@ -1304,12 +1304,12 @@ void *__init fixmap_remap_fdt(phys_addr_t dt_phys, int *size, pgprot_t prot)
 	return dt_virt;
 }
 
-int __init arch_ioremap_p4d_supported(void)
+bool arch_vmap_p4d_supported(pgprot_t prot)
 {
-	return 0;
+	return false;
 }
 
-int __init arch_ioremap_pud_supported(void)
+bool arch_vmap_pud_supported(pgprot_t prot);
 {
 	/*
 	 * Only 4k granule supports level 1 block mappings.
@@ -1319,9 +1319,9 @@ int __init arch_ioremap_pud_supported(void)
 	       !IS_ENABLED(CONFIG_PTDUMP_DEBUGFS);
 }
 
-int __init arch_ioremap_pmd_supported(void)
+bool arch_vmap_pmd_supported(pgprot_t prot)
 {
-	/* See arch_ioremap_pud_supported() */
+	/* See arch_vmap_pud_supported() */
 	return !IS_ENABLED(CONFIG_PTDUMP_DEBUGFS);
 }
 
diff --git a/arch/powerpc/include/asm/vmalloc.h b/arch/powerpc/include/asm/vmalloc.h
index b992dfaaa161..105abb73f075 100644
--- a/arch/powerpc/include/asm/vmalloc.h
+++ b/arch/powerpc/include/asm/vmalloc.h
@@ -1,4 +1,12 @@
 #ifndef _ASM_POWERPC_VMALLOC_H
 #define _ASM_POWERPC_VMALLOC_H
 
+#include <asm/page.h>
+
+#ifdef CONFIG_HAVE_ARCH_HUGE_VMAP
+bool arch_vmap_p4d_supported(pgprot_t prot);
+bool arch_vmap_pud_supported(pgprot_t prot);
+bool arch_vmap_pmd_supported(pgprot_t prot);
+#endif
+
 #endif /* _ASM_POWERPC_VMALLOC_H */
diff --git a/arch/powerpc/mm/book3s64/radix_pgtable.c b/arch/powerpc/mm/book3s64/radix_pgtable.c
index 28c784976bed..eca83a50bf2e 100644
--- a/arch/powerpc/mm/book3s64/radix_pgtable.c
+++ b/arch/powerpc/mm/book3s64/radix_pgtable.c
@@ -1134,13 +1134,13 @@ void radix__ptep_modify_prot_commit(struct vm_area_struct *vma,
 	set_pte_at(mm, addr, ptep, pte);
 }
 
-int __init arch_ioremap_pud_supported(void)
+bool arch_vmap_pud_supported(pgprot_t prot)
 {
 	/* HPT does not cope with large pages in the vmalloc area */
 	return radix_enabled();
 }
 
-int __init arch_ioremap_pmd_supported(void)
+bool arch_vmap_pmd_supported(pgprot_t prot)
 {
 	return radix_enabled();
 }
@@ -1234,7 +1234,7 @@ int pmd_free_pte_page(pmd_t *pmd, unsigned long addr)
 	return 1;
 }
 
-int __init arch_ioremap_p4d_supported(void)
+bool arch_vmap_p4d_supported(pgprot_t prot)
 {
-	return 0;
+	return false;
 }
diff --git a/arch/x86/include/asm/vmalloc.h b/arch/x86/include/asm/vmalloc.h
index 29837740b520..094ea2b565f3 100644
--- a/arch/x86/include/asm/vmalloc.h
+++ b/arch/x86/include/asm/vmalloc.h
@@ -1,6 +1,13 @@
 #ifndef _ASM_X86_VMALLOC_H
 #define _ASM_X86_VMALLOC_H
 
+#include <asm/page.h>
 #include <asm/pgtable_areas.h>
 
+#ifdef CONFIG_HAVE_ARCH_HUGE_VMAP
+bool arch_vmap_p4d_supported(pgprot_t prot);
+bool arch_vmap_pud_supported(pgprot_t prot);
+bool arch_vmap_pmd_supported(pgprot_t prot);
+#endif
+
 #endif /* _ASM_X86_VMALLOC_H */
diff --git a/arch/x86/mm/ioremap.c b/arch/x86/mm/ioremap.c
index 84d85dbd1dad..159bfca757b9 100644
--- a/arch/x86/mm/ioremap.c
+++ b/arch/x86/mm/ioremap.c
@@ -481,21 +481,21 @@ void iounmap(volatile void __iomem *addr)
 }
 EXPORT_SYMBOL(iounmap);
 
-int __init arch_ioremap_p4d_supported(void)
+bool arch_vmap_p4d_supported(pgprot_t prot)
 {
-	return 0;
+	return false;
 }
 
-int __init arch_ioremap_pud_supported(void)
+bool arch_vmap_pud_supported(pgprot_t prot)
 {
 #ifdef CONFIG_X86_64
 	return boot_cpu_has(X86_FEATURE_GBPAGES);
 #else
-	return 0;
+	return false;
 #endif
 }
 
-int __init arch_ioremap_pmd_supported(void)
+bool arch_vmap_pmd_supported(pgprot_t prot)
 {
 	return boot_cpu_has(X86_FEATURE_PSE);
 }
diff --git a/include/linux/io.h b/include/linux/io.h
index 8394c56babc2..f1effd4d7a3c 100644
--- a/include/linux/io.h
+++ b/include/linux/io.h
@@ -31,15 +31,6 @@ static inline int ioremap_page_range(unsigned long addr, unsigned long end,
 }
 #endif
 
-#ifdef CONFIG_HAVE_ARCH_HUGE_VMAP
-void __init ioremap_huge_init(void);
-int arch_ioremap_p4d_supported(void);
-int arch_ioremap_pud_supported(void);
-int arch_ioremap_pmd_supported(void);
-#else
-static inline void ioremap_huge_init(void) { }
-#endif
-
 /*
  * Managed iomap interface
  */
diff --git a/include/linux/vmalloc.h b/include/linux/vmalloc.h
index 0221f852a7e1..3f6bba4cc9bc 100644
--- a/include/linux/vmalloc.h
+++ b/include/linux/vmalloc.h
@@ -84,6 +84,12 @@ struct vmap_area {
 	};
 };
 
+#ifndef CONFIG_HAVE_ARCH_HUGE_VMAP
+static inline bool arch_vmap_p4d_supported(pgprot_t prot) { return false; }
+static inline bool arch_vmap_pud_supported(pgprot_t prot) { return false; }
+static inline bool arch_vmap_pmd_supported(pgprot_t prot) { return false; }
+#endif
+
 /*
  *	Highlevel APIs for driver use
  */
diff --git a/init/main.c b/init/main.c
index ae78fb68d231..1c89aa127b8f 100644
--- a/init/main.c
+++ b/init/main.c
@@ -820,7 +820,6 @@ static void __init mm_init(void)
 	pgtable_init();
 	debug_objects_mem_init();
 	vmalloc_init();
-	ioremap_huge_init();
 	/* Should be run before the first non-init thread is created */
 	init_espfix_bsp();
 	/* Should be run after espfix64 is set up. */
diff --git a/mm/ioremap.c b/mm/ioremap.c
index 3f4d36f9745a..c67f91164401 100644
--- a/mm/ioremap.c
+++ b/mm/ioremap.c
@@ -16,49 +16,16 @@
 #include "pgalloc-track.h"
 
 #ifdef CONFIG_HAVE_ARCH_HUGE_VMAP
-static int __read_mostly ioremap_p4d_capable;
-static int __read_mostly ioremap_pud_capable;
-static int __read_mostly ioremap_pmd_capable;
-static int __read_mostly ioremap_huge_disabled;
+static bool __ro_after_init iomap_max_page_shift = PAGE_SHIFT;
 
 static int __init set_nohugeiomap(char *str)
 {
-	ioremap_huge_disabled = 1;
+	iomap_max_page_shift = P4D_SHIFT;
 	return 0;
 }
 early_param("nohugeiomap", set_nohugeiomap);
-
-void __init ioremap_huge_init(void)
-{
-	if (!ioremap_huge_disabled) {
-		if (arch_ioremap_p4d_supported())
-			ioremap_p4d_capable = 1;
-		if (arch_ioremap_pud_supported())
-			ioremap_pud_capable = 1;
-		if (arch_ioremap_pmd_supported())
-			ioremap_pmd_capable = 1;
-	}
-}
-
-static inline int ioremap_p4d_enabled(void)
-{
-	return ioremap_p4d_capable;
-}
-
-static inline int ioremap_pud_enabled(void)
-{
-	return ioremap_pud_capable;
-}
-
-static inline int ioremap_pmd_enabled(void)
-{
-	return ioremap_pmd_capable;
-}
-
-#else	/* !CONFIG_HAVE_ARCH_HUGE_VMAP */
-static inline int ioremap_p4d_enabled(void) { return 0; }
-static inline int ioremap_pud_enabled(void) { return 0; }
-static inline int ioremap_pmd_enabled(void) { return 0; }
+#else /* CONFIG_HAVE_ARCH_HUGE_VMAP */
+static const bool iomap_max_page_shift = PAGE_SHIFT;
 #endif	/* CONFIG_HAVE_ARCH_HUGE_VMAP */
 
 static int vmap_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end,
@@ -82,9 +49,13 @@ static int vmap_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end,
 }
 
 static int vmap_try_huge_pmd(pmd_t *pmd, unsigned long addr, unsigned long end,
-			phys_addr_t phys_addr, pgprot_t prot)
+			phys_addr_t phys_addr, pgprot_t prot,
+			unsigned int max_page_shift)
 {
-	if (!ioremap_pmd_enabled())
+	if (max_page_shift < PMD_SHIFT)
+		return 0;
+
+	if (!arch_vmap_pmd_supported(prot))
 		return 0;
 
 	if ((end - addr) != PMD_SIZE)
@@ -104,7 +75,7 @@ static int vmap_try_huge_pmd(pmd_t *pmd, unsigned long addr, unsigned long end,
 
 static int vmap_pmd_range(pud_t *pud, unsigned long addr, unsigned long end,
 			phys_addr_t phys_addr, pgprot_t prot,
-			pgtbl_mod_mask *mask)
+			unsigned int max_page_shift, pgtbl_mod_mask *mask)
 {
 	pmd_t *pmd;
 	unsigned long next;
@@ -115,7 +86,7 @@ static int vmap_pmd_range(pud_t *pud, unsigned long addr, unsigned long end,
 	do {
 		next = pmd_addr_end(addr, end);
 
-		if (vmap_try_huge_pmd(pmd, addr, next, phys_addr, prot)) {
+		if (vmap_try_huge_pmd(pmd, addr, next, phys_addr, prot, max_page_shift)) {
 			*mask |= PGTBL_PMD_MODIFIED;
 			continue;
 		}
@@ -127,9 +98,13 @@ static int vmap_pmd_range(pud_t *pud, unsigned long addr, unsigned long end,
 }
 
 static int vmap_try_huge_pud(pud_t *pud, unsigned long addr, unsigned long end,
-			phys_addr_t phys_addr, pgprot_t prot)
+			phys_addr_t phys_addr, pgprot_t prot,
+			unsigned int max_page_shift)
 {
-	if (!ioremap_pud_enabled())
+	if (max_page_shift < PUD_SHIFT)
+		return 0;
+
+	if (!arch_vmap_pud_supported(prot))
 		return 0;
 
 	if ((end - addr) != PUD_SIZE)
@@ -149,7 +124,7 @@ static int vmap_try_huge_pud(pud_t *pud, unsigned long addr, unsigned long end,
 
 static int vmap_pud_range(p4d_t *p4d, unsigned long addr, unsigned long end,
 			phys_addr_t phys_addr, pgprot_t prot,
-			pgtbl_mod_mask *mask)
+			unsigned int max_page_shift, pgtbl_mod_mask *mask)
 {
 	pud_t *pud;
 	unsigned long next;
@@ -160,21 +135,25 @@ static int vmap_pud_range(p4d_t *p4d, unsigned long addr, unsigned long end,
 	do {
 		next = pud_addr_end(addr, end);
 
-		if (vmap_try_huge_pud(pud, addr, next, phys_addr, prot)) {
+		if (vmap_try_huge_pud(pud, addr, next, phys_addr, prot, max_page_shift)) {
 			*mask |= PGTBL_PUD_MODIFIED;
 			continue;
 		}
 
-		if (vmap_pmd_range(pud, addr, next, phys_addr, prot, mask))
+		if (vmap_pmd_range(pud, addr, next, phys_addr, prot, max_page_shift, mask))
 			return -ENOMEM;
 	} while (pud++, phys_addr += (next - addr), addr = next, addr != end);
 	return 0;
 }
 
 static int vmap_try_huge_p4d(p4d_t *p4d, unsigned long addr, unsigned long end,
-			phys_addr_t phys_addr, pgprot_t prot)
+			phys_addr_t phys_addr, pgprot_t prot,
+			unsigned int max_page_shift)
 {
-	if (!ioremap_p4d_enabled())
+	if (max_page_shift < P4D_SHIFT)
+		return 0;
+
+	if (!arch_vmap_p4d_supported(prot))
 		return 0;
 
 	if ((end - addr) != P4D_SIZE)
@@ -194,7 +173,7 @@ static int vmap_try_huge_p4d(p4d_t *p4d, unsigned long addr, unsigned long end,
 
 static int vmap_p4d_range(pgd_t *pgd, unsigned long addr, unsigned long end,
 			phys_addr_t phys_addr, pgprot_t prot,
-			pgtbl_mod_mask *mask)
+			unsigned int max_page_shift, pgtbl_mod_mask *mask)
 {
 	p4d_t *p4d;
 	unsigned long next;
@@ -205,19 +184,20 @@ static int vmap_p4d_range(pgd_t *pgd, unsigned long addr, unsigned long end,
 	do {
 		next = p4d_addr_end(addr, end);
 
-		if (vmap_try_huge_p4d(p4d, addr, next, phys_addr, prot)) {
+		if (vmap_try_huge_p4d(p4d, addr, next, phys_addr, prot, max_page_shift)) {
 			*mask |= PGTBL_P4D_MODIFIED;
 			continue;
 		}
 
-		if (vmap_pud_range(p4d, addr, next, phys_addr, prot, mask))
+		if (vmap_pud_range(p4d, addr, next, phys_addr, prot, max_page_shift, mask))
 			return -ENOMEM;
 	} while (p4d++, phys_addr += (next - addr), addr = next, addr != end);
 	return 0;
 }
 
 static int vmap_range(unsigned long addr, unsigned long end,
-			phys_addr_t phys_addr, pgprot_t prot)
+			phys_addr_t phys_addr, pgprot_t prot,
+			unsigned int max_page_shift)
 {
 	pgd_t *pgd;
 	unsigned long start;
@@ -232,7 +212,7 @@ static int vmap_range(unsigned long addr, unsigned long end,
 	pgd = pgd_offset_k(addr);
 	do {
 		next = pgd_addr_end(addr, end);
-		err = vmap_p4d_range(pgd, addr, next, phys_addr, prot, &mask);
+		err = vmap_p4d_range(pgd, addr, next, phys_addr, prot, max_page_shift, &mask);
 		if (err)
 			break;
 	} while (pgd++, phys_addr += (next - addr), addr = next, addr != end);
@@ -248,7 +228,7 @@ static int vmap_range(unsigned long addr, unsigned long end,
 int ioremap_page_range(unsigned long addr,
 		       unsigned long end, phys_addr_t phys_addr, pgprot_t prot)
 {
-	return vmap_range(addr, end, phys_addr, prot);
+	return vmap_range(addr, end, phys_addr, prot, iomap_max_page_shift);
 }
 
 #ifdef CONFIG_GENERIC_IOREMAP
-- 
2.23.0


^ permalink raw reply related

* [PATCH v7 06/12] powerpc: inline huge vmap supported functions
From: Nicholas Piggin @ 2020-08-25 14:57 UTC (permalink / raw)
  To: linux-mm, Andrew Morton
  Cc: linux-arch, linux-kernel, Nicholas Piggin, Christoph Hellwig,
	Zefan Li, Jonathan Cameron, linuxppc-dev
In-Reply-To: <20200825145753.529284-1-npiggin@gmail.com>

This allows unsupported levels to be constant folded away, and so
p4d_free_pud_page can be removed because it's no longer linked to.

Cc: linuxppc-dev@lists.ozlabs.org
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
---

Ack or objection if this goes via the -mm tree? 

 arch/powerpc/include/asm/vmalloc.h       | 19 ++++++++++++++++---
 arch/powerpc/mm/book3s64/radix_pgtable.c | 21 ---------------------
 2 files changed, 16 insertions(+), 24 deletions(-)

diff --git a/arch/powerpc/include/asm/vmalloc.h b/arch/powerpc/include/asm/vmalloc.h
index 105abb73f075..3f0c153befb0 100644
--- a/arch/powerpc/include/asm/vmalloc.h
+++ b/arch/powerpc/include/asm/vmalloc.h
@@ -1,12 +1,25 @@
 #ifndef _ASM_POWERPC_VMALLOC_H
 #define _ASM_POWERPC_VMALLOC_H
 
+#include <asm/mmu.h>
 #include <asm/page.h>
 
 #ifdef CONFIG_HAVE_ARCH_HUGE_VMAP
-bool arch_vmap_p4d_supported(pgprot_t prot);
-bool arch_vmap_pud_supported(pgprot_t prot);
-bool arch_vmap_pmd_supported(pgprot_t prot);
+static inline bool arch_vmap_p4d_supported(pgprot_t prot)
+{
+	return false;
+}
+
+static inline bool arch_vmap_pud_supported(pgprot_t prot)
+{
+	/* HPT does not cope with large pages in the vmalloc area */
+	return radix_enabled();
+}
+
+static inline bool arch_vmap_pmd_supported(pgprot_t prot)
+{
+	return radix_enabled();
+}
 #endif
 
 #endif /* _ASM_POWERPC_VMALLOC_H */
diff --git a/arch/powerpc/mm/book3s64/radix_pgtable.c b/arch/powerpc/mm/book3s64/radix_pgtable.c
index eca83a50bf2e..27f5837cf145 100644
--- a/arch/powerpc/mm/book3s64/radix_pgtable.c
+++ b/arch/powerpc/mm/book3s64/radix_pgtable.c
@@ -1134,22 +1134,6 @@ void radix__ptep_modify_prot_commit(struct vm_area_struct *vma,
 	set_pte_at(mm, addr, ptep, pte);
 }
 
-bool arch_vmap_pud_supported(pgprot_t prot)
-{
-	/* HPT does not cope with large pages in the vmalloc area */
-	return radix_enabled();
-}
-
-bool arch_vmap_pmd_supported(pgprot_t prot)
-{
-	return radix_enabled();
-}
-
-int p4d_free_pud_page(p4d_t *p4d, unsigned long addr)
-{
-	return 0;
-}
-
 int pud_set_huge(pud_t *pud, phys_addr_t addr, pgprot_t prot)
 {
 	pte_t *ptep = (pte_t *)pud;
@@ -1233,8 +1217,3 @@ int pmd_free_pte_page(pmd_t *pmd, unsigned long addr)
 
 	return 1;
 }
-
-bool arch_vmap_p4d_supported(pgprot_t prot)
-{
-	return false;
-}
-- 
2.23.0


^ permalink raw reply related

* [PATCH v7 07/12] arm64: inline huge vmap supported functions
From: Nicholas Piggin @ 2020-08-25 14:57 UTC (permalink / raw)
  To: linux-mm, Andrew Morton
  Cc: linux-arch, Will Deacon, Catalin Marinas, linux-kernel,
	Nicholas Piggin, Christoph Hellwig, Zefan Li, Jonathan Cameron,
	linuxppc-dev, linux-arm-kernel
In-Reply-To: <20200825145753.529284-1-npiggin@gmail.com>

This allows unsupported levels to be constant folded away, and so
p4d_free_pud_page can be removed because it's no longer linked to.

Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: linux-arm-kernel@lists.infradead.org
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
---

Ack or objection if this goes via the -mm tree?

 arch/arm64/include/asm/vmalloc.h | 23 ++++++++++++++++++++---
 arch/arm64/mm/mmu.c              | 26 --------------------------
 2 files changed, 20 insertions(+), 29 deletions(-)

diff --git a/arch/arm64/include/asm/vmalloc.h b/arch/arm64/include/asm/vmalloc.h
index 597b40405319..fc9a12d6cc1a 100644
--- a/arch/arm64/include/asm/vmalloc.h
+++ b/arch/arm64/include/asm/vmalloc.h
@@ -4,9 +4,26 @@
 #include <asm/page.h>
 
 #ifdef CONFIG_HAVE_ARCH_HUGE_VMAP
-bool arch_vmap_p4d_supported(pgprot_t prot);
-bool arch_vmap_pud_supported(pgprot_t prot);
-bool arch_vmap_pmd_supported(pgprot_t prot);
+static inline bool arch_vmap_p4d_supported(pgprot_t prot)
+{
+	return false;
+}
+
+static inline bool arch_vmap_pud_supported(pgprot_t prot)
+{
+	/*
+	 * Only 4k granule supports level 1 block mappings.
+	 * SW table walks can't handle removal of intermediate entries.
+	 */
+	return IS_ENABLED(CONFIG_ARM64_4K_PAGES) &&
+	       !IS_ENABLED(CONFIG_PTDUMP_DEBUGFS);
+}
+
+static inline bool arch_vmap_pmd_supported(pgprot_t prot)
+{
+	/* See arch_vmap_pud_supported() */
+	return !IS_ENABLED(CONFIG_PTDUMP_DEBUGFS);
+}
 #endif
 
 #endif /* _ASM_ARM64_VMALLOC_H */
diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c
index 9df7e0058c78..07093e148957 100644
--- a/arch/arm64/mm/mmu.c
+++ b/arch/arm64/mm/mmu.c
@@ -1304,27 +1304,6 @@ void *__init fixmap_remap_fdt(phys_addr_t dt_phys, int *size, pgprot_t prot)
 	return dt_virt;
 }
 
-bool arch_vmap_p4d_supported(pgprot_t prot)
-{
-	return false;
-}
-
-bool arch_vmap_pud_supported(pgprot_t prot);
-{
-	/*
-	 * Only 4k granule supports level 1 block mappings.
-	 * SW table walks can't handle removal of intermediate entries.
-	 */
-	return IS_ENABLED(CONFIG_ARM64_4K_PAGES) &&
-	       !IS_ENABLED(CONFIG_PTDUMP_DEBUGFS);
-}
-
-bool arch_vmap_pmd_supported(pgprot_t prot)
-{
-	/* See arch_vmap_pud_supported() */
-	return !IS_ENABLED(CONFIG_PTDUMP_DEBUGFS);
-}
-
 int pud_set_huge(pud_t *pudp, phys_addr_t phys, pgprot_t prot)
 {
 	pud_t new_pud = pfn_pud(__phys_to_pfn(phys), mk_pud_sect_prot(prot));
@@ -1416,11 +1395,6 @@ int pud_free_pmd_page(pud_t *pudp, unsigned long addr)
 	return 1;
 }
 
-int p4d_free_pud_page(p4d_t *p4d, unsigned long addr)
-{
-	return 0;	/* Don't attempt a block mapping */
-}
-
 #ifdef CONFIG_MEMORY_HOTPLUG
 static void __remove_pgd_mapping(pgd_t *pgdir, unsigned long start, u64 size)
 {
-- 
2.23.0


^ permalink raw reply related

* [PATCH v7 08/12] x86: inline huge vmap supported functions
From: Nicholas Piggin @ 2020-08-25 14:57 UTC (permalink / raw)
  To: linux-mm, Andrew Morton
  Cc: linux-arch, H. Peter Anvin, x86, linux-kernel, Nicholas Piggin,
	Christoph Hellwig, Zefan Li, Borislav Petkov, Jonathan Cameron,
	Thomas Gleixner, linuxppc-dev, Ingo Molnar
In-Reply-To: <20200825145753.529284-1-npiggin@gmail.com>

This allows unsupported levels to be constant folded away, and so
p4d_free_pud_page can be removed because it's no longer linked to.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: x86@kernel.org
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
---

Ack or objection if this goes via the -mm tree?

 arch/x86/include/asm/vmalloc.h | 22 +++++++++++++++++++---
 arch/x86/mm/ioremap.c          | 19 -------------------
 arch/x86/mm/pgtable.c          | 13 -------------
 3 files changed, 19 insertions(+), 35 deletions(-)

diff --git a/arch/x86/include/asm/vmalloc.h b/arch/x86/include/asm/vmalloc.h
index 094ea2b565f3..e714b00fc0ca 100644
--- a/arch/x86/include/asm/vmalloc.h
+++ b/arch/x86/include/asm/vmalloc.h
@@ -1,13 +1,29 @@
 #ifndef _ASM_X86_VMALLOC_H
 #define _ASM_X86_VMALLOC_H
 
+#include <asm/cpufeature.h>
 #include <asm/page.h>
 #include <asm/pgtable_areas.h>
 
 #ifdef CONFIG_HAVE_ARCH_HUGE_VMAP
-bool arch_vmap_p4d_supported(pgprot_t prot);
-bool arch_vmap_pud_supported(pgprot_t prot);
-bool arch_vmap_pmd_supported(pgprot_t prot);
+static inline bool arch_vmap_p4d_supported(pgprot_t prot)
+{
+	return false;
+}
+
+static inline bool arch_vmap_pud_supported(pgprot_t prot)
+{
+#ifdef CONFIG_X86_64
+	return boot_cpu_has(X86_FEATURE_GBPAGES);
+#else
+	return false;
+#endif
+}
+
+static inline bool arch_vmap_pmd_supported(pgprot_t prot)
+{
+	return boot_cpu_has(X86_FEATURE_PSE);
+}
 #endif
 
 #endif /* _ASM_X86_VMALLOC_H */
diff --git a/arch/x86/mm/ioremap.c b/arch/x86/mm/ioremap.c
index 159bfca757b9..1465a22a9bfb 100644
--- a/arch/x86/mm/ioremap.c
+++ b/arch/x86/mm/ioremap.c
@@ -481,25 +481,6 @@ void iounmap(volatile void __iomem *addr)
 }
 EXPORT_SYMBOL(iounmap);
 
-bool arch_vmap_p4d_supported(pgprot_t prot)
-{
-	return false;
-}
-
-bool arch_vmap_pud_supported(pgprot_t prot)
-{
-#ifdef CONFIG_X86_64
-	return boot_cpu_has(X86_FEATURE_GBPAGES);
-#else
-	return false;
-#endif
-}
-
-bool arch_vmap_pmd_supported(pgprot_t prot)
-{
-	return boot_cpu_has(X86_FEATURE_PSE);
-}
-
 /*
  * Convert a physical pointer to a virtual kernel pointer for /dev/mem
  * access
diff --git a/arch/x86/mm/pgtable.c b/arch/x86/mm/pgtable.c
index dfd82f51ba66..801c418ee97d 100644
--- a/arch/x86/mm/pgtable.c
+++ b/arch/x86/mm/pgtable.c
@@ -780,14 +780,6 @@ int pmd_clear_huge(pmd_t *pmd)
 	return 0;
 }
 
-/*
- * Until we support 512GB pages, skip them in the vmap area.
- */
-int p4d_free_pud_page(p4d_t *p4d, unsigned long addr)
-{
-	return 0;
-}
-
 #ifdef CONFIG_X86_64
 /**
  * pud_free_pmd_page - Clear pud entry and free pmd page.
@@ -859,11 +851,6 @@ int pmd_free_pte_page(pmd_t *pmd, unsigned long addr)
 
 #else /* !CONFIG_X86_64 */
 
-int pud_free_pmd_page(pud_t *pud, unsigned long addr)
-{
-	return pud_none(*pud);
-}
-
 /*
  * Disable free page handling on x86-PAE. This assures that ioremap()
  * does not update sync'd pmd entries. See vmalloc_sync_one().
-- 
2.23.0


^ permalink raw reply related

* [PATCH v7 09/12] mm: Move vmap_range from mm/ioremap.c to mm/vmalloc.c
From: Nicholas Piggin @ 2020-08-25 14:57 UTC (permalink / raw)
  To: linux-mm, Andrew Morton
  Cc: linux-arch, linux-kernel, Nicholas Piggin, Christoph Hellwig,
	Zefan Li, Jonathan Cameron, linuxppc-dev
In-Reply-To: <20200825145753.529284-1-npiggin@gmail.com>

This is a generic kernel virtual memory mapper, not specific to ioremap.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
---
 include/linux/vmalloc.h |   3 +
 mm/ioremap.c            | 197 ----------------------------------------
 mm/vmalloc.c            | 196 +++++++++++++++++++++++++++++++++++++++
 3 files changed, 199 insertions(+), 197 deletions(-)

diff --git a/include/linux/vmalloc.h b/include/linux/vmalloc.h
index 3f6bba4cc9bc..15adb9a14fb6 100644
--- a/include/linux/vmalloc.h
+++ b/include/linux/vmalloc.h
@@ -177,6 +177,9 @@ extern struct vm_struct *remove_vm_area(const void *addr);
 extern struct vm_struct *find_vm_area(const void *addr);
 
 #ifdef CONFIG_MMU
+int vmap_range(unsigned long addr, unsigned long end,
+			phys_addr_t phys_addr, pgprot_t prot,
+			unsigned int max_page_shift);
 extern int map_kernel_range_noflush(unsigned long start, unsigned long size,
 				    pgprot_t prot, struct page **pages);
 int map_kernel_range(unsigned long start, unsigned long size, pgprot_t prot,
diff --git a/mm/ioremap.c b/mm/ioremap.c
index c67f91164401..d1dcc7e744ac 100644
--- a/mm/ioremap.c
+++ b/mm/ioremap.c
@@ -28,203 +28,6 @@ early_param("nohugeiomap", set_nohugeiomap);
 static const bool iomap_max_page_shift = PAGE_SHIFT;
 #endif	/* CONFIG_HAVE_ARCH_HUGE_VMAP */
 
-static int vmap_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end,
-			phys_addr_t phys_addr, pgprot_t prot,
-			pgtbl_mod_mask *mask)
-{
-	pte_t *pte;
-	u64 pfn;
-
-	pfn = phys_addr >> PAGE_SHIFT;
-	pte = pte_alloc_kernel_track(pmd, addr, mask);
-	if (!pte)
-		return -ENOMEM;
-	do {
-		BUG_ON(!pte_none(*pte));
-		set_pte_at(&init_mm, addr, pte, pfn_pte(pfn, prot));
-		pfn++;
-	} while (pte++, addr += PAGE_SIZE, addr != end);
-	*mask |= PGTBL_PTE_MODIFIED;
-	return 0;
-}
-
-static int vmap_try_huge_pmd(pmd_t *pmd, unsigned long addr, unsigned long end,
-			phys_addr_t phys_addr, pgprot_t prot,
-			unsigned int max_page_shift)
-{
-	if (max_page_shift < PMD_SHIFT)
-		return 0;
-
-	if (!arch_vmap_pmd_supported(prot))
-		return 0;
-
-	if ((end - addr) != PMD_SIZE)
-		return 0;
-
-	if (!IS_ALIGNED(addr, PMD_SIZE))
-		return 0;
-
-	if (!IS_ALIGNED(phys_addr, PMD_SIZE))
-		return 0;
-
-	if (pmd_present(*pmd) && !pmd_free_pte_page(pmd, addr))
-		return 0;
-
-	return pmd_set_huge(pmd, phys_addr, prot);
-}
-
-static int vmap_pmd_range(pud_t *pud, unsigned long addr, unsigned long end,
-			phys_addr_t phys_addr, pgprot_t prot,
-			unsigned int max_page_shift, pgtbl_mod_mask *mask)
-{
-	pmd_t *pmd;
-	unsigned long next;
-
-	pmd = pmd_alloc_track(&init_mm, pud, addr, mask);
-	if (!pmd)
-		return -ENOMEM;
-	do {
-		next = pmd_addr_end(addr, end);
-
-		if (vmap_try_huge_pmd(pmd, addr, next, phys_addr, prot, max_page_shift)) {
-			*mask |= PGTBL_PMD_MODIFIED;
-			continue;
-		}
-
-		if (vmap_pte_range(pmd, addr, next, phys_addr, prot, mask))
-			return -ENOMEM;
-	} while (pmd++, phys_addr += (next - addr), addr = next, addr != end);
-	return 0;
-}
-
-static int vmap_try_huge_pud(pud_t *pud, unsigned long addr, unsigned long end,
-			phys_addr_t phys_addr, pgprot_t prot,
-			unsigned int max_page_shift)
-{
-	if (max_page_shift < PUD_SHIFT)
-		return 0;
-
-	if (!arch_vmap_pud_supported(prot))
-		return 0;
-
-	if ((end - addr) != PUD_SIZE)
-		return 0;
-
-	if (!IS_ALIGNED(addr, PUD_SIZE))
-		return 0;
-
-	if (!IS_ALIGNED(phys_addr, PUD_SIZE))
-		return 0;
-
-	if (pud_present(*pud) && !pud_free_pmd_page(pud, addr))
-		return 0;
-
-	return pud_set_huge(pud, phys_addr, prot);
-}
-
-static int vmap_pud_range(p4d_t *p4d, unsigned long addr, unsigned long end,
-			phys_addr_t phys_addr, pgprot_t prot,
-			unsigned int max_page_shift, pgtbl_mod_mask *mask)
-{
-	pud_t *pud;
-	unsigned long next;
-
-	pud = pud_alloc_track(&init_mm, p4d, addr, mask);
-	if (!pud)
-		return -ENOMEM;
-	do {
-		next = pud_addr_end(addr, end);
-
-		if (vmap_try_huge_pud(pud, addr, next, phys_addr, prot, max_page_shift)) {
-			*mask |= PGTBL_PUD_MODIFIED;
-			continue;
-		}
-
-		if (vmap_pmd_range(pud, addr, next, phys_addr, prot, max_page_shift, mask))
-			return -ENOMEM;
-	} while (pud++, phys_addr += (next - addr), addr = next, addr != end);
-	return 0;
-}
-
-static int vmap_try_huge_p4d(p4d_t *p4d, unsigned long addr, unsigned long end,
-			phys_addr_t phys_addr, pgprot_t prot,
-			unsigned int max_page_shift)
-{
-	if (max_page_shift < P4D_SHIFT)
-		return 0;
-
-	if (!arch_vmap_p4d_supported(prot))
-		return 0;
-
-	if ((end - addr) != P4D_SIZE)
-		return 0;
-
-	if (!IS_ALIGNED(addr, P4D_SIZE))
-		return 0;
-
-	if (!IS_ALIGNED(phys_addr, P4D_SIZE))
-		return 0;
-
-	if (p4d_present(*p4d) && !p4d_free_pud_page(p4d, addr))
-		return 0;
-
-	return p4d_set_huge(p4d, phys_addr, prot);
-}
-
-static int vmap_p4d_range(pgd_t *pgd, unsigned long addr, unsigned long end,
-			phys_addr_t phys_addr, pgprot_t prot,
-			unsigned int max_page_shift, pgtbl_mod_mask *mask)
-{
-	p4d_t *p4d;
-	unsigned long next;
-
-	p4d = p4d_alloc_track(&init_mm, pgd, addr, mask);
-	if (!p4d)
-		return -ENOMEM;
-	do {
-		next = p4d_addr_end(addr, end);
-
-		if (vmap_try_huge_p4d(p4d, addr, next, phys_addr, prot, max_page_shift)) {
-			*mask |= PGTBL_P4D_MODIFIED;
-			continue;
-		}
-
-		if (vmap_pud_range(p4d, addr, next, phys_addr, prot, max_page_shift, mask))
-			return -ENOMEM;
-	} while (p4d++, phys_addr += (next - addr), addr = next, addr != end);
-	return 0;
-}
-
-static int vmap_range(unsigned long addr, unsigned long end,
-			phys_addr_t phys_addr, pgprot_t prot,
-			unsigned int max_page_shift)
-{
-	pgd_t *pgd;
-	unsigned long start;
-	unsigned long next;
-	int err;
-	pgtbl_mod_mask mask = 0;
-
-	might_sleep();
-	BUG_ON(addr >= end);
-
-	start = addr;
-	pgd = pgd_offset_k(addr);
-	do {
-		next = pgd_addr_end(addr, end);
-		err = vmap_p4d_range(pgd, addr, next, phys_addr, prot, max_page_shift, &mask);
-		if (err)
-			break;
-	} while (pgd++, phys_addr += (next - addr), addr = next, addr != end);
-
-	flush_cache_vmap(start, end);
-
-	if (mask & ARCH_PAGE_TABLE_SYNC_MASK)
-		arch_sync_kernel_mappings(start, end);
-
-	return err;
-}
-
 int ioremap_page_range(unsigned long addr,
 		       unsigned long end, phys_addr_t phys_addr, pgprot_t prot)
 {
diff --git a/mm/vmalloc.c b/mm/vmalloc.c
index 45cd80ec7eeb..256554d598e6 100644
--- a/mm/vmalloc.c
+++ b/mm/vmalloc.c
@@ -70,6 +70,202 @@ static void free_work(struct work_struct *w)
 }
 
 /*** Page table manipulation functions ***/
+static int vmap_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end,
+			phys_addr_t phys_addr, pgprot_t prot,
+			pgtbl_mod_mask *mask)
+{
+	pte_t *pte;
+	u64 pfn;
+
+	pfn = phys_addr >> PAGE_SHIFT;
+	pte = pte_alloc_kernel_track(pmd, addr, mask);
+	if (!pte)
+		return -ENOMEM;
+	do {
+		BUG_ON(!pte_none(*pte));
+		set_pte_at(&init_mm, addr, pte, pfn_pte(pfn, prot));
+		pfn++;
+	} while (pte++, addr += PAGE_SIZE, addr != end);
+	*mask |= PGTBL_PTE_MODIFIED;
+	return 0;
+}
+
+static int vmap_try_huge_pmd(pmd_t *pmd, unsigned long addr, unsigned long end,
+			phys_addr_t phys_addr, pgprot_t prot,
+			unsigned int max_page_shift)
+{
+	if (max_page_shift < PMD_SHIFT)
+		return 0;
+
+	if (!arch_vmap_pmd_supported(prot))
+		return 0;
+
+	if ((end - addr) != PMD_SIZE)
+		return 0;
+
+	if (!IS_ALIGNED(addr, PMD_SIZE))
+		return 0;
+
+	if (!IS_ALIGNED(phys_addr, PMD_SIZE))
+		return 0;
+
+	if (pmd_present(*pmd) && !pmd_free_pte_page(pmd, addr))
+		return 0;
+
+	return pmd_set_huge(pmd, phys_addr, prot);
+}
+
+static int vmap_pmd_range(pud_t *pud, unsigned long addr, unsigned long end,
+			phys_addr_t phys_addr, pgprot_t prot,
+			unsigned int max_page_shift, pgtbl_mod_mask *mask)
+{
+	pmd_t *pmd;
+	unsigned long next;
+
+	pmd = pmd_alloc_track(&init_mm, pud, addr, mask);
+	if (!pmd)
+		return -ENOMEM;
+	do {
+		next = pmd_addr_end(addr, end);
+
+		if (vmap_try_huge_pmd(pmd, addr, next, phys_addr, prot, max_page_shift)) {
+			*mask |= PGTBL_PMD_MODIFIED;
+			continue;
+		}
+
+		if (vmap_pte_range(pmd, addr, next, phys_addr, prot, mask))
+			return -ENOMEM;
+	} while (pmd++, phys_addr += (next - addr), addr = next, addr != end);
+	return 0;
+}
+
+static int vmap_try_huge_pud(pud_t *pud, unsigned long addr, unsigned long end,
+			phys_addr_t phys_addr, pgprot_t prot,
+			unsigned int max_page_shift)
+{
+	if (max_page_shift < PUD_SHIFT)
+		return 0;
+
+	if (!arch_vmap_pud_supported(prot))
+		return 0;
+
+	if ((end - addr) != PUD_SIZE)
+		return 0;
+
+	if (!IS_ALIGNED(addr, PUD_SIZE))
+		return 0;
+
+	if (!IS_ALIGNED(phys_addr, PUD_SIZE))
+		return 0;
+
+	if (pud_present(*pud) && !pud_free_pmd_page(pud, addr))
+		return 0;
+
+	return pud_set_huge(pud, phys_addr, prot);
+}
+
+static int vmap_pud_range(p4d_t *p4d, unsigned long addr, unsigned long end,
+			phys_addr_t phys_addr, pgprot_t prot,
+			unsigned int max_page_shift, pgtbl_mod_mask *mask)
+{
+	pud_t *pud;
+	unsigned long next;
+
+	pud = pud_alloc_track(&init_mm, p4d, addr, mask);
+	if (!pud)
+		return -ENOMEM;
+	do {
+		next = pud_addr_end(addr, end);
+
+		if (vmap_try_huge_pud(pud, addr, next, phys_addr, prot, max_page_shift)) {
+			*mask |= PGTBL_PUD_MODIFIED;
+			continue;
+		}
+
+		if (vmap_pmd_range(pud, addr, next, phys_addr, prot, max_page_shift, mask))
+			return -ENOMEM;
+	} while (pud++, phys_addr += (next - addr), addr = next, addr != end);
+	return 0;
+}
+
+static int vmap_try_huge_p4d(p4d_t *p4d, unsigned long addr, unsigned long end,
+			phys_addr_t phys_addr, pgprot_t prot,
+			unsigned int max_page_shift)
+{
+	if (max_page_shift < P4D_SHIFT)
+		return 0;
+
+	if (!arch_vmap_p4d_supported(prot))
+		return 0;
+
+	if ((end - addr) != P4D_SIZE)
+		return 0;
+
+	if (!IS_ALIGNED(addr, P4D_SIZE))
+		return 0;
+
+	if (!IS_ALIGNED(phys_addr, P4D_SIZE))
+		return 0;
+
+	if (p4d_present(*p4d) && !p4d_free_pud_page(p4d, addr))
+		return 0;
+
+	return p4d_set_huge(p4d, phys_addr, prot);
+}
+
+static int vmap_p4d_range(pgd_t *pgd, unsigned long addr, unsigned long end,
+			phys_addr_t phys_addr, pgprot_t prot,
+			unsigned int max_page_shift, pgtbl_mod_mask *mask)
+{
+	p4d_t *p4d;
+	unsigned long next;
+
+	p4d = p4d_alloc_track(&init_mm, pgd, addr, mask);
+	if (!p4d)
+		return -ENOMEM;
+	do {
+		next = p4d_addr_end(addr, end);
+
+		if (vmap_try_huge_p4d(p4d, addr, next, phys_addr, prot, max_page_shift)) {
+			*mask |= PGTBL_P4D_MODIFIED;
+			continue;
+		}
+
+		if (vmap_pud_range(p4d, addr, next, phys_addr, prot, max_page_shift, mask))
+			return -ENOMEM;
+	} while (p4d++, phys_addr += (next - addr), addr = next, addr != end);
+	return 0;
+}
+
+int vmap_range(unsigned long addr, unsigned long end,
+			phys_addr_t phys_addr, pgprot_t prot,
+			unsigned int max_page_shift)
+{
+	pgd_t *pgd;
+	unsigned long start;
+	unsigned long next;
+	int err;
+	pgtbl_mod_mask mask = 0;
+
+	might_sleep();
+	BUG_ON(addr >= end);
+
+	start = addr;
+	pgd = pgd_offset_k(addr);
+	do {
+		next = pgd_addr_end(addr, end);
+		err = vmap_p4d_range(pgd, addr, next, phys_addr, prot, max_page_shift, &mask);
+		if (err)
+			break;
+	} while (pgd++, phys_addr += (next - addr), addr = next, addr != end);
+
+	flush_cache_vmap(start, end);
+
+	if (mask & ARCH_PAGE_TABLE_SYNC_MASK)
+		arch_sync_kernel_mappings(start, end);
+
+	return err;
+}
 
 static void vunmap_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end,
 			     pgtbl_mod_mask *mask)
-- 
2.23.0


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