[PATCH V3 02/16] powerpc/vas: Move VAS API to common book3s platform

Haren Myneni
2021-04-17T21:02:46Z

Using the same /dev/crypto/nx-gzip interface for both powerNV and
pseries. So this patch creates platforms/book3s/ and moves VAS API
to that directory. The actual functionality is not changed.

Common interface functions such as open, window open ioctl, mmap
and close are moved to arch/powerpc/platforms/book3s/vas-api.c
Added hooks to call platform specific code, but the underline
powerNV code in these functions is not changed.

Signed-off-by: Haren Myneni <haren@linux.ibm.com>
---
arch/powerpc/include/asm/vas.h | 22 ++++++-
arch/powerpc/platforms/Kconfig | 1 +
arch/powerpc/platforms/Makefile | 1 +
arch/powerpc/platforms/book3s/Kconfig | 15 +++++
arch/powerpc/platforms/book3s/Makefile | 2 +
.../platforms/{powernv => book3s}/vas-api.c | 64 ++++++++++--------
arch/powerpc/platforms/powernv/Kconfig | 14 ----
arch/powerpc/platforms/powernv/Makefile | 2 +-
arch/powerpc/platforms/powernv/vas-window.c | 66 +++++++++++++++++++
9 files changed, 143 insertions(+), 44 deletions(-)
create mode 100644 arch/powerpc/platforms/book3s/Kconfig
create mode 100644 arch/powerpc/platforms/book3s/Makefile
rename arch/powerpc/platforms/{powernv => book3s}/vas-api.c (83%)

diff --git a/arch/powerpc/include/asm/vas.h b/arch/powerpc/include/asm/vas.h
index 41f73fae7ab8..6bbade60d8f4 100644
--- a/arch/powerpc/include/asm/vas.h
+++ b/arch/powerpc/include/asm/vas.h
@@ -5,6 +5,8 @@

#ifndef _ASM_POWERPC_VAS_H
#define _ASM_POWERPC_VAS_H
+#include <uapi/asm/vas-api.h>
+

struct vas_window;

@@ -48,6 +50,16 @@ enum vas_cop_type {
VAS_COP_TYPE_MAX,
};

+/*
+ * User space window operations used for powernv and powerVM
+ */
+struct vas_user_win_ops {
+ struct vas_window * (*open_win)(struct vas_tx_win_open_attr *,
+ enum vas_cop_type);
+ u64 (*paste_addr)(void *);
+ int (*close_win)(void *);
+};
+
/*
* Receive window attributes specified by the (in-kernel) owner of window.
*/
@@ -161,6 +173,9 @@ int vas_copy_crb(void *crb, int offset);
* assumed to be true for NX windows.
*/
int vas_paste_crb(struct vas_window *win, int offset, bool re);
+int vas_register_api_powernv(struct module *mod, enum vas_cop_type cop_type,
+ const char *name);
+void vas_unregister_api_powernv(void);

/*
* Register / unregister coprocessor type to VAS API which will be exported
@@ -170,8 +185,9 @@ int vas_paste_crb(struct vas_window *win, int offset, bool re);
* Only NX GZIP coprocessor type is supported now, but this API can be
* used for others in future.
*/
-int vas_register_api_powernv(struct module *mod, enum vas_cop_type cop_type,
- const char *name);
-void vas_unregister_api_powernv(void);
+int vas_register_coproc_api(struct module *mod, enum vas_cop_type cop_type,
+ const char *name,
+ struct vas_user_win_ops *vops);
+void vas_unregister_coproc_api(void);

#endif /* __ASM_POWERPC_VAS_H */
diff --git a/arch/powerpc/platforms/Kconfig b/arch/powerpc/platforms/Kconfig
index 7a5e8f4541e3..594544a65b02 100644
--- a/arch/powerpc/platforms/Kconfig
+++ b/arch/powerpc/platforms/Kconfig
@@ -20,6 +20,7 @@ source "arch/powerpc/platforms/embedded6xx/Kconfig"
source "arch/powerpc/platforms/44x/Kconfig"
source "arch/powerpc/platforms/40x/Kconfig"
source "arch/powerpc/platforms/amigaone/Kconfig"
+source "arch/powerpc/platforms/book3s/Kconfig"

config KVM_GUEST
bool "KVM Guest support"
diff --git a/arch/powerpc/platforms/Makefile b/arch/powerpc/platforms/Makefile
index 143d4417f6cc..0e75d7df387b 100644
--- a/arch/powerpc/platforms/Makefile
+++ b/arch/powerpc/platforms/Makefile
@@ -22,3 +22,4 @@ obj-$(CONFIG_PPC_CELL) += cell/
obj-$(CONFIG_PPC_PS3) += ps3/
obj-$(CONFIG_EMBEDDED6xx) += embedded6xx/
obj-$(CONFIG_AMIGAONE) += amigaone/
+obj-$(CONFIG_PPC_BOOK3S) += book3s/
diff --git a/arch/powerpc/platforms/book3s/Kconfig b/arch/powerpc/platforms/book3s/Kconfig
new file mode 100644
index 000000000000..51e14db83a79
--- /dev/null
+++ b/arch/powerpc/platforms/book3s/Kconfig
@@ -0,0 +1,15 @@
+# SPDX-License-Identifier: GPL-2.0
+config PPC_VAS
+ bool "IBM Virtual Accelerator Switchboard (VAS)"
+ depends on PPC_POWERNV && PPC_64K_PAGES
+ default y
+ help
+ This enables support for IBM Virtual Accelerator Switchboard (VAS).
+
+ VAS allows accelerators in co-processors like NX-GZIP and NX-842
+ to be accessible to kernel subsystems and user processes.
+ VAS adapters are found in POWER9 and later based systems.
+ The user mode NX-GZIP support is added on P9 for powerNV and on
+ P10 for powerVM.
+
+ If unsure, say "N".
diff --git a/arch/powerpc/platforms/book3s/Makefile b/arch/powerpc/platforms/book3s/Makefile
new file mode 100644
index 000000000000..e790f1910f61
--- /dev/null
+++ b/arch/powerpc/platforms/book3s/Makefile
@@ -0,0 +1,2 @@
+# SPDX-License-Identifier: GPL-2.0-only
+obj-$(CONFIG_PPC_VAS) += vas-api.o
diff --git a/arch/powerpc/platforms/powernv/vas-api.c b/arch/powerpc/platforms/book3s/vas-api.c
similarity index 83%
rename from arch/powerpc/platforms/powernv/vas-api.c
rename to arch/powerpc/platforms/book3s/vas-api.c
index 72d8ce39e56c..05d7b99acf41 100644
--- a/arch/powerpc/platforms/powernv/vas-api.c
+++ b/arch/powerpc/platforms/book3s/vas-api.c
@@ -4,15 +4,20 @@
* Copyright (C) 2019 Haren Myneni, IBM Corp
*/

+#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/device.h>
#include <linux/cdev.h>
#include <linux/fs.h>
#include <linux/slab.h>
#include <linux/uaccess.h>
+#include <linux/kthread.h>
+#include <linux/sched/signal.h>
+#include <linux/sched/mm.h>
+#include <linux/mmu_context.h>
#include <asm/vas.h>
+#include <asm/icswx.h>
#include <uapi/asm/vas-api.h>
-#include "vas.h"

/*
* The driver creates the device node that can be used as follows:
@@ -42,6 +47,7 @@ static struct coproc_dev {
dev_t devt;
struct class *class;
enum vas_cop_type cop_type;
+ struct vas_user_win_ops *vops;
} coproc_device;

struct coproc_instance {
@@ -72,11 +78,10 @@ static int coproc_open(struct inode *inode, struct file *fp)
static int coproc_ioc_tx_win_open(struct file *fp, unsigned long arg)
{
void __user *uptr = (void __user *)arg;
- struct vas_tx_win_attr txattr = {};
struct vas_tx_win_open_attr uattr;
struct coproc_instance *cp_inst;
struct vas_window *txwin;
- int rc, vasid;
+ int rc;

cp_inst = fp->private_data;

@@ -93,27 +98,20 @@ static int coproc_ioc_tx_win_open(struct file *fp, unsigned long arg)
}

if (uattr.version != 1) {
- pr_err("Invalid version\n");
+ pr_err("Invalid window open API version\n");
return -EINVAL;
}

- vasid = uattr.vas_id;
-
- vas_init_tx_win_attr(&txattr, cp_inst->coproc->cop_type);
-
- txattr.lpid = mfspr(SPRN_LPID);
- txattr.pidr = mfspr(SPRN_PID);
- txattr.user_win = true;
- txattr.rsvd_txbuf_count = false;
- txattr.pswid = false;
-
- pr_devel("Pid %d: Opening txwin, PIDR %ld\n", txattr.pidr,
- mfspr(SPRN_PID));
+ if (!cp_inst->coproc->vops && !cp_inst->coproc->vops->open_win) {
+ pr_err("VAS API is not registered\n");
+ return -EACCES;
+ }

- txwin = vas_tx_win_open(vasid, cp_inst->coproc->cop_type, &txattr);
+ txwin = cp_inst->coproc->vops->open_win(&uattr,
+ cp_inst->coproc->cop_type);
if (IS_ERR(txwin)) {
- pr_err("%s() vas_tx_win_open() failed, %ld\n", __func__,
- PTR_ERR(txwin));
+ pr_err("%s() VAS window open failed, %ld\n", __func__,
+ PTR_ERR(txwin));
return PTR_ERR(txwin);
}

@@ -125,9 +123,14 @@ static int coproc_ioc_tx_win_open(struct file *fp, unsigned long arg)
static int coproc_release(struct inode *inode, struct file *fp)
{
struct coproc_instance *cp_inst = fp->private_data;
+ int rc = 0;

if (cp_inst->txwin) {
- vas_win_close(cp_inst->txwin);
+ if (cp_inst->coproc->vops && cp_inst->coproc->vops->close_win) {
+ rc = cp_inst->coproc->vops->close_win(cp_inst->txwin);
+ if (rc)
+ return rc;
+ }
cp_inst->txwin = NULL;
}

@@ -168,7 +171,17 @@ static int coproc_mmap(struct file *fp, struct vm_area_struct *vma)
return -EINVAL;
}

- vas_win_paste_addr(txwin, &paste_addr, NULL);
+ if (!cp_inst->coproc->vops && !cp_inst->coproc->vops->paste_addr) {
+ pr_err("%s(): VAS API is not registered\n", __func__);
+ return -EACCES;
+ }
+
+ paste_addr = cp_inst->coproc->vops->paste_addr(txwin);
+ if (!paste_addr) {
+ pr_err("%s(): Window paste address failed\n", __func__);
+ return -EINVAL;
+ }
+
pfn = paste_addr >> PAGE_SHIFT;

/* flags, page_prot from cxl_mmap(), except we want cachable */
@@ -207,8 +220,8 @@ static struct file_operations coproc_fops = {
* Supporting only nx-gzip coprocessor type now, but this API code
* extended to other coprocessor types later.
*/
-int vas_register_api_powernv(struct module *mod, enum vas_cop_type cop_type,
- const char *name)
+int vas_register_coproc_api(struct module *mod, enum vas_cop_type cop_type,
+ const char *name, struct vas_user_win_ops *vops)
{
int rc = -EINVAL;
dev_t devno;
@@ -230,6 +243,7 @@ int vas_register_api_powernv(struct module *mod, enum vas_cop_type cop_type,
}
coproc_device.class->devnode = coproc_devnode;
coproc_device.cop_type = cop_type;
+ coproc_device.vops = vops;

coproc_fops.owner = mod;
cdev_init(&coproc_device.cdev, &coproc_fops);
@@ -262,9 +276,8 @@ int vas_register_api_powernv(struct module *mod, enum vas_cop_type cop_type,
unregister_chrdev_region(coproc_device.devt, 1);
return rc;
}
-EXPORT_SYMBOL_GPL(vas_register_api_powernv);

-void vas_unregister_api_powernv(void)
+void vas_unregister_coproc_api(void)
{
dev_t devno;

@@ -275,4 +288,3 @@ void vas_unregister_api_powernv(void)
class_destroy(coproc_device.class);
unregister_chrdev_region(coproc_device.devt, 1);
}
-EXPORT_SYMBOL_GPL(vas_unregister_api_powernv);
diff --git a/arch/powerpc/platforms/powernv/Kconfig b/arch/powerpc/platforms/powernv/Kconfig
index 619b093a0657..043eefbbdd28 100644
--- a/arch/powerpc/platforms/powernv/Kconfig
+++ b/arch/powerpc/platforms/powernv/Kconfig
@@ -33,20 +33,6 @@ config PPC_MEMTRACE
Enabling this option allows for runtime allocation of memory (RAM)
for hardware tracing.

-config PPC_VAS
- bool "IBM Virtual Accelerator Switchboard (VAS)"
- depends on PPC_POWERNV && PPC_64K_PAGES
- default y
- help
- This enables support for IBM Virtual Accelerator Switchboard (VAS).
-
- VAS allows accelerators in co-processors like NX-GZIP and NX-842
- to be accessible to kernel subsystems and user processes.
-
- VAS adapters are found in POWER9 based systems.
-
- If unsure, say N.
-
config SCOM_DEBUGFS
bool "Expose SCOM controllers via debugfs"
depends on DEBUG_FS
diff --git a/arch/powerpc/platforms/powernv/Makefile b/arch/powerpc/platforms/powernv/Makefile
index 2eb6ae150d1f..c747a1f1d25b 100644
--- a/arch/powerpc/platforms/powernv/Makefile
+++ b/arch/powerpc/platforms/powernv/Makefile
@@ -18,7 +18,7 @@ obj-$(CONFIG_MEMORY_FAILURE) += opal-memory-errors.o
obj-$(CONFIG_OPAL_PRD) += opal-prd.o
obj-$(CONFIG_PERF_EVENTS) += opal-imc.o
obj-$(CONFIG_PPC_MEMTRACE) += memtrace.o
-obj-$(CONFIG_PPC_VAS) += vas.o vas-window.o vas-debug.o vas-fault.o vas-api.o
+obj-$(CONFIG_PPC_VAS) += vas.o vas-window.o vas-debug.o vas-fault.o
obj-$(CONFIG_OCXL_BASE) += ocxl.o
obj-$(CONFIG_SCOM_DEBUGFS) += opal-xscom.o
obj-$(CONFIG_PPC_SECURE_BOOT) += opal-secvar.o
diff --git a/arch/powerpc/platforms/powernv/vas-window.c b/arch/powerpc/platforms/powernv/vas-window.c
index 5f5fe63a3d1c..b973dd574b47 100644
--- a/arch/powerpc/platforms/powernv/vas-window.c
+++ b/arch/powerpc/platforms/powernv/vas-window.c
@@ -16,6 +16,8 @@
#include <linux/mmu_context.h>
#include <asm/switch_to.h>
#include <asm/ppc-opcode.h>
+#include <asm/vas.h>
+#include <uapi/asm/vas-api.h>
#include "vas.h"
#include "copy-paste.h"

@@ -1441,3 +1443,67 @@ struct vas_window *vas_pswid_to_window(struct vas_instance *vinst,

return window;
}
+
+static struct vas_window *vas_user_win_open(struct vas_tx_win_open_attr *uattr,
+ enum vas_cop_type cop_type)
+{
+ struct vas_tx_win_attr txattr = {};
+
+ vas_init_tx_win_attr(&txattr, cop_type);
+
+ txattr.lpid = mfspr(SPRN_LPID);
+ txattr.pidr = mfspr(SPRN_PID);
+ txattr.user_win = true;
+ txattr.rsvd_txbuf_count = false;
+ txattr.pswid = false;
+
+ pr_devel("Pid %d: Opening txwin, PIDR %ld\n", txattr.pidr,
+ mfspr(SPRN_PID));
+
+ return vas_tx_win_open(uattr->vas_id, cop_type, &txattr);
+}
+
+static u64 vas_user_win_paste_addr(void *addr)
+{
+ u64 paste_addr;
+
+ vas_win_paste_addr((struct vas_window *)addr, &paste_addr, NULL);
+
+ return paste_addr;
+}
+
+static int vas_user_win_close(void *addr)
+{
+ struct vas_window *txwin = addr;
+
+ vas_win_close(txwin);
+
+ return 0;
+}
+
+static struct vas_user_win_ops vops = {
+ .open_win = vas_user_win_open,
+ .paste_addr = vas_user_win_paste_addr,
+ .close_win = vas_user_win_close,
+};
+
+/*
+ * Supporting only nx-gzip coprocessor type now, but this API code
+ * extended to other coprocessor types later.
+ */
+int vas_register_api_powernv(struct module *mod, enum vas_cop_type cop_type,
+ const char *name)
+{
+ int rc;
+
+ rc = vas_register_coproc_api(mod, cop_type, name, &vops);
+
+ return rc;
+}
+EXPORT_SYMBOL_GPL(vas_register_api_powernv);
+
+void vas_unregister_api_powernv(void)
+{
+ vas_unregister_coproc_api();
+}
+EXPORT_SYMBOL_GPL(vas_unregister_api_powernv);
--
2.18.2