From 638c1fd3033c76778e6d9975ad8a4a9cdd5b96d9 Mon Sep 17 00:00:00 2001 From: Matthew Garrett Date: Thu, 21 Jul 2011 16:57:52 -0400 Subject: pstore: Extend API for more flexibility in new backends Some pstore implementations may not have a static context, so extend the API to pass the pstore_info struct to all calls and allow for a context pointer. Signed-off-by: Matthew Garrett Signed-off-by: Tony Luck --- fs/pstore/platform.c | 13 +++++++------ 1 file changed, 7 insertions(+), 6 deletions(-) (limited to 'fs/pstore/platform.c') diff --git a/fs/pstore/platform.c b/fs/pstore/platform.c index f2c3ff20ea68..221c04e5e333 100644 --- a/fs/pstore/platform.c +++ b/fs/pstore/platform.c @@ -94,11 +94,12 @@ static void pstore_dump(struct kmsg_dumper *dumper, memcpy(dst, s1 + s1_start, l1_cpy); memcpy(dst + l1_cpy, s2 + s2_start, l2_cpy); - id = psinfo->write(PSTORE_TYPE_DMESG, hsize + l1_cpy + l2_cpy); + id = psinfo->write(PSTORE_TYPE_DMESG, hsize + l1_cpy + l2_cpy, + psinfo); if (reason == KMSG_DUMP_OOPS && pstore_is_mounted()) pstore_mkfile(PSTORE_TYPE_DMESG, psinfo->name, id, psinfo->buf, hsize + l1_cpy + l2_cpy, - CURRENT_TIME, psinfo->erase); + CURRENT_TIME, psinfo); l1 -= l1_cpy; l2 -= l2_cpy; total += l1_cpy + l2_cpy; @@ -166,9 +167,9 @@ void pstore_get_records(void) if (rc) goto out; - while ((size = psi->read(&id, &type, &time)) > 0) { + while ((size = psi->read(&id, &type, &time, psi)) > 0) { if (pstore_mkfile(type, psi->name, id, psi->buf, (size_t)size, - time, psi->erase)) + time, psi)) failed++; } psi->close(psi); @@ -196,10 +197,10 @@ int pstore_write(enum pstore_type_id type, char *buf, size_t size) mutex_lock(&psinfo->buf_mutex); memcpy(psinfo->buf, buf, size); - id = psinfo->write(type, size); + id = psinfo->write(type, size, psinfo); if (pstore_is_mounted()) pstore_mkfile(PSTORE_TYPE_DMESG, psinfo->name, id, psinfo->buf, - size, CURRENT_TIME, psinfo->erase); + size, CURRENT_TIME, psinfo); mutex_unlock(&psinfo->buf_mutex); return 0; -- cgit v1.2.3 From 56280682ceeef74b692b3e21d1872049eea7c887 Mon Sep 17 00:00:00 2001 From: Matthew Garrett Date: Thu, 21 Jul 2011 16:57:53 -0400 Subject: pstore: Add extra context for writes and erases EFI only provides small amounts of individual storage, and conventionally puts metadata in the storage variable name. Rather than add a metadata header to the (already limited) variable storage, it's easier for us to modify pstore to pass all the information we need to construct a unique variable name to the appropriate functions. Signed-off-by: Matthew Garrett Signed-off-by: Tony Luck --- drivers/acpi/apei/erst.c | 10 ++++++---- fs/pstore/inode.c | 6 ++++-- fs/pstore/platform.c | 9 +++++---- include/linux/pstore.h | 5 +++-- 4 files changed, 18 insertions(+), 12 deletions(-) (limited to 'fs/pstore/platform.c') diff --git a/drivers/acpi/apei/erst.c b/drivers/acpi/apei/erst.c index de3ae92adaa5..d842ac4f8cfe 100644 --- a/drivers/acpi/apei/erst.c +++ b/drivers/acpi/apei/erst.c @@ -933,9 +933,10 @@ static int erst_open_pstore(struct pstore_info *psi); static int erst_close_pstore(struct pstore_info *psi); static ssize_t erst_reader(u64 *id, enum pstore_type_id *type, struct timespec *time, struct pstore_info *psi); -static u64 erst_writer(enum pstore_type_id type, size_t size, +static u64 erst_writer(enum pstore_type_id type, int part, size_t size, struct pstore_info *psi); -static int erst_clearer(u64 id, struct pstore_info *psi); +static int erst_clearer(enum pstore_type_id type, u64 id, + struct pstore_info *psi); static struct pstore_info erst_info = { .owner = THIS_MODULE, @@ -1039,7 +1040,7 @@ out: return (rc < 0) ? rc : (len - sizeof(*rcd)); } -static u64 erst_writer(enum pstore_type_id type, size_t size, +static u64 erst_writer(enum pstore_type_id type, int part, size_t size, struct pstore_info *psi) { struct cper_pstore_record *rcd = (struct cper_pstore_record *) @@ -1083,7 +1084,8 @@ static u64 erst_writer(enum pstore_type_id type, size_t size, return rcd->hdr.record_id; } -static int erst_clearer(u64 id, struct pstore_info *psi) +static int erst_clearer(enum pstore_type_id type, u64 id, + struct pstore_info *psi) { return erst_clear(id); } diff --git a/fs/pstore/inode.c b/fs/pstore/inode.c index b19884a1ba77..893b961dcfd8 100644 --- a/fs/pstore/inode.c +++ b/fs/pstore/inode.c @@ -39,8 +39,9 @@ #define PSTORE_NAMELEN 64 struct pstore_private { - u64 id; struct pstore_info *psi; + enum pstore_type_id type; + u64 id; ssize_t size; char data[]; }; @@ -73,7 +74,7 @@ static int pstore_unlink(struct inode *dir, struct dentry *dentry) { struct pstore_private *p = dentry->d_inode->i_private; - p->psi->erase(p->id, p->psi); + p->psi->erase(p->type, p->id, p->psi); return simple_unlink(dir, dentry); } @@ -192,6 +193,7 @@ int pstore_mkfile(enum pstore_type_id type, char *psname, u64 id, private = kmalloc(sizeof *private + size, GFP_KERNEL); if (!private) goto fail_alloc; + private->type = type; private->id = id; private->psi = psi; diff --git a/fs/pstore/platform.c b/fs/pstore/platform.c index 221c04e5e333..163bb40511e7 100644 --- a/fs/pstore/platform.c +++ b/fs/pstore/platform.c @@ -78,7 +78,7 @@ static void pstore_dump(struct kmsg_dumper *dumper, oopscount++; while (total < kmsg_bytes) { dst = psinfo->buf; - hsize = sprintf(dst, "%s#%d Part%d\n", why, oopscount, part++); + hsize = sprintf(dst, "%s#%d Part%d\n", why, oopscount, part); size = psinfo->bufsize - hsize; dst += hsize; @@ -94,8 +94,8 @@ static void pstore_dump(struct kmsg_dumper *dumper, memcpy(dst, s1 + s1_start, l1_cpy); memcpy(dst + l1_cpy, s2 + s2_start, l2_cpy); - id = psinfo->write(PSTORE_TYPE_DMESG, hsize + l1_cpy + l2_cpy, - psinfo); + id = psinfo->write(PSTORE_TYPE_DMESG, part, + hsize + l1_cpy + l2_cpy, psinfo); if (reason == KMSG_DUMP_OOPS && pstore_is_mounted()) pstore_mkfile(PSTORE_TYPE_DMESG, psinfo->name, id, psinfo->buf, hsize + l1_cpy + l2_cpy, @@ -103,6 +103,7 @@ static void pstore_dump(struct kmsg_dumper *dumper, l1 -= l1_cpy; l2 -= l2_cpy; total += l1_cpy + l2_cpy; + part++; } mutex_unlock(&psinfo->buf_mutex); } @@ -197,7 +198,7 @@ int pstore_write(enum pstore_type_id type, char *buf, size_t size) mutex_lock(&psinfo->buf_mutex); memcpy(psinfo->buf, buf, size); - id = psinfo->write(type, size, psinfo); + id = psinfo->write(type, 0, size, psinfo); if (pstore_is_mounted()) pstore_mkfile(PSTORE_TYPE_DMESG, psinfo->name, id, psinfo->buf, size, CURRENT_TIME, psinfo); diff --git a/include/linux/pstore.h b/include/linux/pstore.h index b2f1d97f6909..12be8f193d09 100644 --- a/include/linux/pstore.h +++ b/include/linux/pstore.h @@ -39,9 +39,10 @@ struct pstore_info { int (*close)(struct pstore_info *psi); ssize_t (*read)(u64 *id, enum pstore_type_id *type, struct timespec *time, struct pstore_info *psi); - u64 (*write)(enum pstore_type_id type, size_t size, + u64 (*write)(enum pstore_type_id type, int part, + size_t size, struct pstore_info *psi); + int (*erase)(enum pstore_type_id type, u64 id, struct pstore_info *psi); - int (*erase)(u64 id, struct pstore_info *psi); void *data; }; -- cgit v1.2.3 From b94fdd077eef5e6cab56836bf62695b497946716 Mon Sep 17 00:00:00 2001 From: Matthew Garrett Date: Thu, 21 Jul 2011 16:57:54 -0400 Subject: pstore: Make "part" unsigned We'll never have a negative part, so just make this an unsigned int. Signed-off-by: Matthew Garrett Signed-off-by: Tony Luck --- drivers/acpi/apei/erst.c | 8 ++++---- fs/pstore/platform.c | 3 ++- include/linux/pstore.h | 2 +- 3 files changed, 7 insertions(+), 6 deletions(-) (limited to 'fs/pstore/platform.c') diff --git a/drivers/acpi/apei/erst.c b/drivers/acpi/apei/erst.c index d842ac4f8cfe..6053f4780df9 100644 --- a/drivers/acpi/apei/erst.c +++ b/drivers/acpi/apei/erst.c @@ -933,8 +933,8 @@ static int erst_open_pstore(struct pstore_info *psi); static int erst_close_pstore(struct pstore_info *psi); static ssize_t erst_reader(u64 *id, enum pstore_type_id *type, struct timespec *time, struct pstore_info *psi); -static u64 erst_writer(enum pstore_type_id type, int part, size_t size, - struct pstore_info *psi); +static u64 erst_writer(enum pstore_type_id type, unsigned int part, + size_t size, struct pstore_info *psi); static int erst_clearer(enum pstore_type_id type, u64 id, struct pstore_info *psi); @@ -1040,8 +1040,8 @@ out: return (rc < 0) ? rc : (len - sizeof(*rcd)); } -static u64 erst_writer(enum pstore_type_id type, int part, size_t size, - struct pstore_info *psi) +static u64 erst_writer(enum pstore_type_id type, unsigned int part, + size_t size, struct pstore_info *psi) { struct cper_pstore_record *rcd = (struct cper_pstore_record *) (erst_info.buf - sizeof(*rcd)); diff --git a/fs/pstore/platform.c b/fs/pstore/platform.c index 163bb40511e7..49ff1de2178a 100644 --- a/fs/pstore/platform.c +++ b/fs/pstore/platform.c @@ -67,7 +67,8 @@ static void pstore_dump(struct kmsg_dumper *dumper, unsigned long size, total = 0; char *dst, *why; u64 id; - int hsize, part = 1; + int hsize; + unsigned int part = 1; if (reason < ARRAY_SIZE(reason_str)) why = reason_str[reason]; diff --git a/include/linux/pstore.h b/include/linux/pstore.h index 12be8f193d09..cc03bbf5c4b8 100644 --- a/include/linux/pstore.h +++ b/include/linux/pstore.h @@ -39,7 +39,7 @@ struct pstore_info { int (*close)(struct pstore_info *psi); ssize_t (*read)(u64 *id, enum pstore_type_id *type, struct timespec *time, struct pstore_info *psi); - u64 (*write)(enum pstore_type_id type, int part, + u64 (*write)(enum pstore_type_id type, unsigned int part, size_t size, struct pstore_info *psi); int (*erase)(enum pstore_type_id type, u64 id, struct pstore_info *psi); -- cgit v1.2.3 From dee28e72b619b48ec80a9e5509db458dbe66f71f Mon Sep 17 00:00:00 2001 From: Matthew Garrett Date: Thu, 21 Jul 2011 16:57:55 -0400 Subject: pstore: Allow the user to explicitly choose a backend pstore only allows one backend to be registered at present, but the system may provide several. Add a parameter to allow the user to choose which backend will be used rather than just relying on load order. Signed-off-by: Matthew Garrett Signed-off-by: Tony Luck --- Documentation/ABI/testing/pstore | 6 ++++++ Documentation/kernel-parameters.txt | 2 ++ fs/pstore/platform.c | 11 +++++++++++ 3 files changed, 19 insertions(+) (limited to 'fs/pstore/platform.c') diff --git a/Documentation/ABI/testing/pstore b/Documentation/ABI/testing/pstore index ddf451ee2a08..ff1df4e3b059 100644 --- a/Documentation/ABI/testing/pstore +++ b/Documentation/ABI/testing/pstore @@ -39,3 +39,9 @@ Description: Generic interface to platform dependent persistent storage. multiple) files based on the record size of the underlying persistent storage until at least this amount is reached. Default is 10 Kbytes. + + Pstore only supports one backend at a time. If multiple + backends are available, the preferred backend may be + set by passing the pstore.backend= argument to the kernel at + boot time. + diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index aa47be71df4c..8789d0c9291a 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -2151,6 +2151,8 @@ bytes respectively. Such letter suffixes can also be entirely omitted. [HW,MOUSE] Controls Logitech smartscroll autorepeat. 0 = disabled, 1 = enabled (default). + pstore.backend= Specify the name of the pstore backend to use + pt. [PARIDE] See Documentation/blockdev/paride.txt. diff --git a/fs/pstore/platform.c b/fs/pstore/platform.c index 49ff1de2178a..c5300ec31696 100644 --- a/fs/pstore/platform.c +++ b/fs/pstore/platform.c @@ -37,6 +37,8 @@ static DEFINE_SPINLOCK(pstore_lock); static struct pstore_info *psinfo; +static char *backend; + /* How much of the console log to snapshot */ static unsigned long kmsg_bytes = 10240; @@ -131,6 +133,12 @@ int pstore_register(struct pstore_info *psi) spin_unlock(&pstore_lock); return -EBUSY; } + + if (backend && strcmp(backend, psi->name)) { + spin_unlock(&pstore_lock); + return -EINVAL; + } + psinfo = psi; spin_unlock(&pstore_lock); @@ -208,3 +216,6 @@ int pstore_write(enum pstore_type_id type, char *buf, size_t size) return 0; } EXPORT_SYMBOL_GPL(pstore_write); + +module_param(backend, charp, 0444); +MODULE_PARM_DESC(backend, "Pstore backend to use"); -- cgit v1.2.3