From 755d4fe46529018ae45bc7c86df682de45ace764 Mon Sep 17 00:00:00 2001 From: Seiji Aguchi Date: Mon, 26 Nov 2012 16:07:44 -0800 Subject: [PATCH] efi_pstore: Add a sequence counter to a variable name [Issue] Currently, a variable name, which identifies each entry, consists of type, id and ctime. But if multiple events happens in a short time, a second/third event may fail to log because efi_pstore can't distinguish each event with current variable name. [Solution] A reasonable way to identify all events precisely is introducing a sequence counter to the variable name. The sequence counter has already supported in a pstore layer with "oopscount". So, this patch adds it to a variable name. Also, it is passed to read/erase callbacks of platform drivers in accordance with the modification of the variable name. a variable name of first event: dump-type0-1-12345678 a variable name of second event: dump-type0-1-12345678 type:0 id:1 ctime:12345678 If multiple events happen in a short time, efi_pstore can't distinguish them because variable names are same among them. it can be distinguishable by adding a sequence counter as follows. a variable name of first event: dump-type0-1-1-12345678 a variable name of Second event: dump-type0-1-2-12345678 type:0 id:1 sequence counter: 1(first event), 2(second event) ctime:12345678 In case of a write callback executed in pstore_console_write(), "0" is added to an argument of the write callback because it just logs all kernel messages and doesn't need to care about multiple events. Signed-off-by: Seiji Aguchi Acked-by: Rafael J. Wysocki Acked-by: Mike Waychison Signed-off-by: Tony Luck --- drivers/acpi/apei/erst.c | 12 ++++++------ drivers/firmware/efivars.c | 23 ++++++++++++++--------- fs/pstore/inode.c | 8 +++++--- fs/pstore/internal.h | 2 +- fs/pstore/platform.c | 13 +++++++------ fs/pstore/ram.c | 7 +++---- include/linux/pstore.h | 8 +++++--- 7 files changed, 41 insertions(+), 32 deletions(-) diff --git a/drivers/acpi/apei/erst.c b/drivers/acpi/apei/erst.c index 0bd6ae4a899f..6d894bfd8b8f 100644 --- a/drivers/acpi/apei/erst.c +++ b/drivers/acpi/apei/erst.c @@ -931,13 +931,13 @@ static int erst_check_table(struct acpi_table_erst *erst_tab) 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, +static ssize_t erst_reader(u64 *id, enum pstore_type_id *type, int *count, struct timespec *time, char **buf, struct pstore_info *psi); static int erst_writer(enum pstore_type_id type, enum kmsg_dump_reason reason, - u64 *id, unsigned int part, + u64 *id, unsigned int part, int count, size_t size, struct pstore_info *psi); -static int erst_clearer(enum pstore_type_id type, u64 id, +static int erst_clearer(enum pstore_type_id type, u64 id, int count, struct timespec time, struct pstore_info *psi); static struct pstore_info erst_info = { @@ -987,7 +987,7 @@ static int erst_close_pstore(struct pstore_info *psi) return 0; } -static ssize_t erst_reader(u64 *id, enum pstore_type_id *type, +static ssize_t erst_reader(u64 *id, enum pstore_type_id *type, int *count, struct timespec *time, char **buf, struct pstore_info *psi) { @@ -1055,7 +1055,7 @@ out: } static int erst_writer(enum pstore_type_id type, enum kmsg_dump_reason reason, - u64 *id, unsigned int part, + u64 *id, unsigned int part, int count, size_t size, struct pstore_info *psi) { struct cper_pstore_record *rcd = (struct cper_pstore_record *) @@ -1101,7 +1101,7 @@ static int erst_writer(enum pstore_type_id type, enum kmsg_dump_reason reason, return ret; } -static int erst_clearer(enum pstore_type_id type, u64 id, +static int erst_clearer(enum pstore_type_id type, u64 id, int count, struct timespec time, struct pstore_info *psi) { return erst_clear(id); diff --git a/drivers/firmware/efivars.c b/drivers/firmware/efivars.c index 3803621c0d45..7ad3aae6e085 100644 --- a/drivers/firmware/efivars.c +++ b/drivers/firmware/efivars.c @@ -658,13 +658,14 @@ static int efi_pstore_close(struct pstore_info *psi) } static ssize_t efi_pstore_read(u64 *id, enum pstore_type_id *type, - struct timespec *timespec, + int *count, struct timespec *timespec, char **buf, struct pstore_info *psi) { efi_guid_t vendor = LINUX_EFI_CRASH_GUID; struct efivars *efivars = psi->data; char name[DUMP_NAME_LEN]; int i; + int cnt; unsigned int part, size; unsigned long time; @@ -674,8 +675,10 @@ static ssize_t efi_pstore_read(u64 *id, enum pstore_type_id *type, for (i = 0; i < DUMP_NAME_LEN; i++) { name[i] = efivars->walk_entry->var.VariableName[i]; } - if (sscanf(name, "dump-type%u-%u-%lu", type, &part, &time) == 3) { + if (sscanf(name, "dump-type%u-%u-%d-%lu", + type, &part, &cnt, &time) == 4) { *id = part; + *count = cnt; timespec->tv_sec = time; timespec->tv_nsec = 0; get_var_data_locked(efivars, &efivars->walk_entry->var); @@ -698,7 +701,8 @@ static ssize_t efi_pstore_read(u64 *id, enum pstore_type_id *type, static int efi_pstore_write(enum pstore_type_id type, enum kmsg_dump_reason reason, u64 *id, - unsigned int part, size_t size, struct pstore_info *psi) + unsigned int part, int count, size_t size, + struct pstore_info *psi) { char name[DUMP_NAME_LEN]; efi_char16_t efi_name[DUMP_NAME_LEN]; @@ -725,7 +729,7 @@ static int efi_pstore_write(enum pstore_type_id type, return -ENOSPC; } - sprintf(name, "dump-type%u-%u-%lu", type, part, + sprintf(name, "dump-type%u-%u-%d-%lu", type, part, count, get_seconds()); for (i = 0; i < DUMP_NAME_LEN; i++) @@ -746,7 +750,7 @@ static int efi_pstore_write(enum pstore_type_id type, return ret; }; -static int efi_pstore_erase(enum pstore_type_id type, u64 id, +static int efi_pstore_erase(enum pstore_type_id type, u64 id, int count, struct timespec time, struct pstore_info *psi) { char name[DUMP_NAME_LEN]; @@ -756,7 +760,7 @@ static int efi_pstore_erase(enum pstore_type_id type, u64 id, struct efivar_entry *entry, *found = NULL; int i; - sprintf(name, "dump-type%u-%u-%lu", type, (unsigned int)id, + sprintf(name, "dump-type%u-%u-%d-%lu", type, (unsigned int)id, count, time.tv_sec); spin_lock(&efivars->lock); @@ -807,7 +811,7 @@ static int efi_pstore_close(struct pstore_info *psi) return 0; } -static ssize_t efi_pstore_read(u64 *id, enum pstore_type_id *type, +static ssize_t efi_pstore_read(u64 *id, enum pstore_type_id *type, int *count, struct timespec *timespec, char **buf, struct pstore_info *psi) { @@ -816,12 +820,13 @@ static ssize_t efi_pstore_read(u64 *id, enum pstore_type_id *type, static int efi_pstore_write(enum pstore_type_id type, enum kmsg_dump_reason reason, u64 *id, - unsigned int part, size_t size, struct pstore_info *psi) + unsigned int part, int count, size_t size, + struct pstore_info *psi) { return 0; } -static int efi_pstore_erase(enum pstore_type_id type, u64 id, +static int efi_pstore_erase(enum pstore_type_id type, u64 id, int count, struct timespec time, struct pstore_info *psi) { return 0; diff --git a/fs/pstore/inode.c b/fs/pstore/inode.c index 4300af654710..ed1d8c7212da 100644 --- a/fs/pstore/inode.c +++ b/fs/pstore/inode.c @@ -49,6 +49,7 @@ struct pstore_private { struct pstore_info *psi; enum pstore_type_id type; u64 id; + int count; ssize_t size; char data[]; }; @@ -175,8 +176,8 @@ static int pstore_unlink(struct inode *dir, struct dentry *dentry) struct pstore_private *p = dentry->d_inode->i_private; if (p->psi->erase) - p->psi->erase(p->type, p->id, dentry->d_inode->i_ctime, - p->psi); + p->psi->erase(p->type, p->id, p->count, + dentry->d_inode->i_ctime, p->psi); return simple_unlink(dir, dentry); } @@ -271,7 +272,7 @@ int pstore_is_mounted(void) * Load it up with "size" bytes of data from "buf". * Set the mtime & ctime to the date that this record was originally stored. */ -int pstore_mkfile(enum pstore_type_id type, char *psname, u64 id, +int pstore_mkfile(enum pstore_type_id type, char *psname, u64 id, int count, char *data, size_t size, struct timespec time, struct pstore_info *psi) { @@ -307,6 +308,7 @@ int pstore_mkfile(enum pstore_type_id type, char *psname, u64 id, goto fail_alloc; private->type = type; private->id = id; + private->count = count; private->psi = psi; switch (type) { diff --git a/fs/pstore/internal.h b/fs/pstore/internal.h index 4847f588b7d5..937d820f273c 100644 --- a/fs/pstore/internal.h +++ b/fs/pstore/internal.h @@ -50,7 +50,7 @@ extern struct pstore_info *psinfo; extern void pstore_set_kmsg_bytes(int); extern void pstore_get_records(int); extern int pstore_mkfile(enum pstore_type_id, char *psname, u64 id, - char *data, size_t size, + int count, char *data, size_t size, struct timespec time, struct pstore_info *psi); extern int pstore_is_mounted(void); diff --git a/fs/pstore/platform.c b/fs/pstore/platform.c index 947fbe06c3b1..5ea2e77ff023 100644 --- a/fs/pstore/platform.c +++ b/fs/pstore/platform.c @@ -136,7 +136,7 @@ static void pstore_dump(struct kmsg_dumper *dumper, break; ret = psinfo->write(PSTORE_TYPE_DMESG, reason, &id, part, - hsize + len, psinfo); + oopscount, hsize + len, psinfo); if (ret == 0 && reason == KMSG_DUMP_OOPS && pstore_is_mounted()) pstore_new_entry = 1; @@ -173,7 +173,7 @@ static void pstore_console_write(struct console *con, const char *s, unsigned c) spin_lock_irqsave(&psinfo->buf_lock, flags); } memcpy(psinfo->buf, s, c); - psinfo->write(PSTORE_TYPE_CONSOLE, 0, &id, 0, c, psinfo); + psinfo->write(PSTORE_TYPE_CONSOLE, 0, &id, 0, 0, c, psinfo); spin_unlock_irqrestore(&psinfo->buf_lock, flags); s += c; c = e - s; @@ -197,7 +197,7 @@ static void pstore_register_console(void) {} static int pstore_write_compat(enum pstore_type_id type, enum kmsg_dump_reason reason, - u64 *id, unsigned int part, + u64 *id, unsigned int part, int count, size_t size, struct pstore_info *psi) { return psi->write_buf(type, reason, id, part, psinfo->buf, size, psi); @@ -267,6 +267,7 @@ void pstore_get_records(int quiet) char *buf = NULL; ssize_t size; u64 id; + int count; enum pstore_type_id type; struct timespec time; int failed = 0, rc; @@ -278,9 +279,9 @@ void pstore_get_records(int quiet) if (psi->open && psi->open(psi)) goto out; - while ((size = psi->read(&id, &type, &time, &buf, psi)) > 0) { - rc = pstore_mkfile(type, psi->name, id, buf, (size_t)size, - time, psi); + while ((size = psi->read(&id, &type, &count, &time, &buf, psi)) > 0) { + rc = pstore_mkfile(type, psi->name, id, count, buf, + (size_t)size, time, psi); kfree(buf); buf = NULL; if (rc && (rc != -EEXIST || !quiet)) diff --git a/fs/pstore/ram.c b/fs/pstore/ram.c index 749693fcb75a..2bfa36e0ffe8 100644 --- a/fs/pstore/ram.c +++ b/fs/pstore/ram.c @@ -132,9 +132,8 @@ ramoops_get_next_prz(struct persistent_ram_zone *przs[], uint *c, uint max, } static ssize_t ramoops_pstore_read(u64 *id, enum pstore_type_id *type, - struct timespec *time, - char **buf, - struct pstore_info *psi) + int *count, struct timespec *time, + char **buf, struct pstore_info *psi) { ssize_t size; struct ramoops_context *cxt = psi->data; @@ -236,7 +235,7 @@ static int notrace ramoops_pstore_write_buf(enum pstore_type_id type, return 0; } -static int ramoops_pstore_erase(enum pstore_type_id type, u64 id, +static int ramoops_pstore_erase(enum pstore_type_id type, u64 id, int count, struct timespec time, struct pstore_info *psi) { struct ramoops_context *cxt = psi->data; diff --git a/include/linux/pstore.h b/include/linux/pstore.h index f6e93362d259..1788909d9a99 100644 --- a/include/linux/pstore.h +++ b/include/linux/pstore.h @@ -50,17 +50,19 @@ struct pstore_info { int (*open)(struct pstore_info *psi); int (*close)(struct pstore_info *psi); ssize_t (*read)(u64 *id, enum pstore_type_id *type, - struct timespec *time, char **buf, + int *count, struct timespec *time, char **buf, struct pstore_info *psi); int (*write)(enum pstore_type_id type, enum kmsg_dump_reason reason, u64 *id, - unsigned int part, size_t size, struct pstore_info *psi); + unsigned int part, int count, size_t size, + struct pstore_info *psi); int (*write_buf)(enum pstore_type_id type, enum kmsg_dump_reason reason, u64 *id, unsigned int part, const char *buf, size_t size, struct pstore_info *psi); int (*erase)(enum pstore_type_id type, u64 id, - struct timespec time, struct pstore_info *psi); + int count, struct timespec time, + struct pstore_info *psi); void *data; };