From: WeiXiong Liao <[email protected]> Support backend for console. To enable console backend, just make console_size be greater than 0 and a multiple of 4096.
Signed-off-by: WeiXiong Liao <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Kees Cook <[email protected]> --- fs/pstore/Kconfig | 12 +++++++ fs/pstore/blk.c | 12 ++++++- fs/pstore/zone.c | 67 +++++++++++++++++++++++++++++++++++-- include/linux/pstore_zone.h | 4 ++- 4 files changed, 90 insertions(+), 5 deletions(-) diff --git a/fs/pstore/Kconfig b/fs/pstore/Kconfig index f18cd126d83f..f1484f751c5e 100644 --- a/fs/pstore/Kconfig +++ b/fs/pstore/Kconfig @@ -236,3 +236,15 @@ config PSTORE_BLK_PMSG_SIZE NOTE that, both Kconfig and module parameters can configure pstore/blk, but module parameters have priority over Kconfig. + +config PSTORE_BLK_CONSOLE_SIZE + int "Size in Kbytes of console to store" + depends on PSTORE_BLK + depends on PSTORE_CONSOLE + default 64 + help + This just sets size of console (console_size) for pstore/blk. The + size is in KB and must be a multiple of 4. + + NOTE that, both Kconfig and module parameters can configure + pstore/blk, but module parameters have priority over Kconfig. diff --git a/fs/pstore/blk.c b/fs/pstore/blk.c index 401e5ba66a5f..813025ea7edd 100644 --- a/fs/pstore/blk.c +++ b/fs/pstore/blk.c @@ -32,6 +32,14 @@ static long pmsg_size = -1; module_param(pmsg_size, long, 0400); MODULE_PARM_DESC(pmsg_size, "pmsg size in kbytes"); +#if IS_ENABLED(CONFIG_PSTORE_CONSOLE) +static long console_size = CONFIG_PSTORE_BLK_CONSOLE_SIZE; +#else +static long console_size = -1; +#endif +module_param(console_size, long, 0400); +MODULE_PARM_DESC(console_size, "console size in kbytes"); + /* * blkdev - The block device to use. * @@ -83,7 +91,8 @@ static struct bdev_info { * whole disk). * On success, the number of bytes should be returned, others * means error. - * @write: The same as @read. + * @write: The same as @read, but the following error number: + * -EBUSY means try to write again later. * @panic_write:The write operation only used for panic case. It's optional * if you do not care panic log. The parameters and return value * are the same as @read. @@ -133,6 +142,7 @@ static int psblk_register_do(struct psblk_device *dev) verify_size(kmsg_size, 4096, dev->flags & PSTORE_FLAGS_DMESG); verify_size(pmsg_size, 4096, dev->flags & PSTORE_FLAGS_PMSG); + verify_size(console_size, 4096, dev->flags & PSTORE_FLAGS_CONSOLE); #undef verify_size pstore_zone_info->total_size = dev->total_size; diff --git a/fs/pstore/zone.c b/fs/pstore/zone.c index f472b06a6c14..0b952eea39fe 100644 --- a/fs/pstore/zone.c +++ b/fs/pstore/zone.c @@ -87,10 +87,12 @@ struct pstore_zone { * * @opszs: oops/panic storage zones * @ppsz: pmsg storage zone + * @cpsz: console storage zone * @oops_max_cnt: max count of @opszs * @oops_read_cnt: counter to read oops zone * @oops_write_cnt: counter to write * @pmsg_read_cnt: counter to read pmsg zone + * @console_read_cnt: counter to read console zone * @oops_counter: counter to oops * @panic_counter: counter to panic * @recovered: whether finish recovering data from storage @@ -102,10 +104,12 @@ struct pstore_zone { struct psz_context { struct pstore_zone **opszs; struct pstore_zone *ppsz; + struct pstore_zone *cpsz; unsigned int oops_max_cnt; unsigned int oops_read_cnt; unsigned int oops_write_cnt; unsigned int pmsg_read_cnt; + unsigned int console_read_cnt; /* * the counter should be recovered when recover. * It records the oops/panic times after burning rather than booting. @@ -125,6 +129,9 @@ struct psz_context { }; static struct psz_context psz_cxt; +static void psz_flush_all_dirty_zones(struct work_struct *); +static DECLARE_WORK(psz_cleaner, psz_flush_all_dirty_zones); + /** * enum psz_flush_mode - flush mode for psz_zone_write() * @@ -235,6 +242,9 @@ static int psz_zone_write(struct pstore_zone *zone, return 0; dirty: atomic_set(&zone->dirty, true); + /* flush dirty zones nicely */ + if (wcnt == -EBUSY && !is_on_panic()) + schedule_work(&psz_cleaner); return -EBUSY; } @@ -291,6 +301,15 @@ static int psz_move_zone(struct pstore_zone *old, struct pstore_zone *new) return 0; } +static void psz_flush_all_dirty_zones(struct work_struct *work) +{ + struct psz_context *cxt = &psz_cxt; + + psz_flush_dirty_zone(cxt->ppsz); + psz_flush_dirty_zone(cxt->cpsz); + psz_flush_dirty_zones(cxt->opszs, cxt->oops_max_cnt); +} + static int psz_recover_oops_data(struct psz_context *cxt) { struct pstore_zone_info *info = cxt->pstore_zone_info; @@ -546,6 +565,10 @@ static inline int psz_recovery(struct psz_context *cxt) if (ret) goto recover_fail; + ret = psz_recover_zone(cxt, cxt->cpsz); + if (ret) + goto recover_fail; + pr_debug("recover end!\n"); atomic_set(&cxt->recovered, 1); return 0; @@ -561,6 +584,7 @@ static int psz_pstore_open(struct pstore_info *psi) cxt->oops_read_cnt = 0; cxt->pmsg_read_cnt = 0; + cxt->console_read_cnt = 0; return 0; } @@ -625,8 +649,9 @@ static int psz_pstore_erase(struct pstore_record *record) return psz_oops_erase(cxt, cxt->opszs[record->id], record); case PSTORE_TYPE_PMSG: return psz_record_erase(cxt, cxt->ppsz); - default: - return -EINVAL; + case PSTORE_TYPE_CONSOLE: + return psz_record_erase(cxt, cxt->cpsz); + default: return -EINVAL; } } @@ -753,9 +778,18 @@ static int notrace psz_pstore_write(struct pstore_record *record) record->reason == KMSG_DUMP_PANIC) atomic_set(&cxt->on_panic, 1); + /* + * if on panic, do not write except panic records + * Fix case that panic_write prints log which wakes up console backend. + */ + if (is_on_panic() && record->type != PSTORE_TYPE_DMESG) + return -EBUSY; + switch (record->type) { case PSTORE_TYPE_DMESG: return psz_oops_write(cxt, record); + case PSTORE_TYPE_CONSOLE: + return psz_record_write(cxt->cpsz, record); case PSTORE_TYPE_PMSG: return psz_record_write(cxt->ppsz, record); default: @@ -780,6 +814,13 @@ static struct pstore_zone *psz_read_next_zone(struct psz_context *cxt) return zone; } + if (cxt->console_read_cnt == 0) { + cxt->console_read_cnt++; + zone = cxt->cpsz; + if (psz_old_ok(zone)) + return zone; + } + return NULL; } @@ -890,6 +931,8 @@ static ssize_t psz_pstore_read(struct pstore_record *record) readop = psz_oops_read; record->id = cxt->oops_read_cnt - 1; break; + case PSTORE_TYPE_CONSOLE: + fallthrough; case PSTORE_TYPE_PMSG: readop = psz_record_read; break; @@ -1037,6 +1080,8 @@ static void psz_free_all_zones(struct psz_context *cxt) psz_free_zones(&cxt->opszs, &cxt->oops_max_cnt); if (cxt->ppsz) psz_free_zone(&cxt->ppsz); + if (cxt->cpsz) + psz_free_zone(&cxt->cpsz); } static int psz_alloc_zones(struct psz_context *cxt) @@ -1053,6 +1098,14 @@ static int psz_alloc_zones(struct psz_context *cxt) goto free_out; } + off_size += info->console_size; + cxt->cpsz = psz_init_zone(PSTORE_TYPE_CONSOLE, &off, + info->console_size); + if (IS_ERR(cxt->cpsz)) { + err = PTR_ERR(cxt->cpsz); + goto free_out; + } + cxt->opszs = psz_init_zones(PSTORE_TYPE_DMESG, &off, info->total_size - off_size, info->kmsg_size, &cxt->oops_max_cnt); @@ -1086,7 +1139,7 @@ int register_pstore_zone(struct pstore_zone_info *info) return -EINVAL; } - if (!info->kmsg_size && !info->pmsg_size) { + if (!info->kmsg_size && !info->pmsg_size && !info->console_size) { pr_warn("at least one of the records be non-zero\n"); return -EINVAL; } @@ -1114,6 +1167,7 @@ int register_pstore_zone(struct pstore_zone_info *info) check_size(total_size, 4096); check_size(kmsg_size, SECTOR_SIZE); check_size(pmsg_size, SECTOR_SIZE); + check_size(console_size, SECTOR_SIZE); #undef check_size @@ -1141,6 +1195,7 @@ int register_pstore_zone(struct pstore_zone_info *info) pr_debug("\ttotal size : %ld Bytes\n", info->total_size); pr_debug("\toops size : %ld Bytes\n", info->kmsg_size); pr_debug("\tpmsg size : %ld Bytes\n", info->pmsg_size); + pr_debug("\tconsole size : %ld Bytes\n", info->console_size); err = psz_alloc_zones(cxt); if (err) { @@ -1173,6 +1228,10 @@ int register_pstore_zone(struct pstore_zone_info *info) cxt->pstore.flags |= PSTORE_FLAGS_PMSG; pr_cont(" pmsg"); } + if (info->console_size) { + cxt->pstore.flags |= PSTORE_FLAGS_CONSOLE; + pr_cont(" console"); + } pr_cont("\n"); err = pstore_register(&cxt->pstore); @@ -1204,6 +1263,8 @@ void unregister_pstore_zone(struct pstore_zone_info *info) { struct psz_context *cxt = &psz_cxt; + flush_work(&psz_cleaner); + pstore_unregister(&cxt->pstore); kfree(cxt->pstore.buf); cxt->pstore.bufsize = 0; diff --git a/include/linux/pstore_zone.h b/include/linux/pstore_zone.h index 39c2cb944123..da294e6d7661 100644 --- a/include/linux/pstore_zone.h +++ b/include/linux/pstore_zone.h @@ -18,11 +18,12 @@ typedef ssize_t (*psz_write_op)(const char *, size_t, loff_t); * it must be multiple of SECTOR_SIZE(512 Bytes). * @max_reason: Maximum kmsg dump reason to store. * @pmsg_size: The size of pmsg zone which is the same as @kmsg_size. + * @console_size:The size of console zone which is the same as @kmsg_size. * @read: The general read operation. Both of the function parameters * @size and @offset are relative value to storage. * On success, the number of bytes should be returned, others * means error. - * @write: The same as @read. + * @write: The same as @read, but -EBUSY means try to write again later. * @panic_write:The write operation only used for panic case. It's optional * if you do not care panic log. The parameters and return value * are the same as @read. @@ -35,6 +36,7 @@ struct pstore_zone_info { unsigned long kmsg_size; int max_reason; unsigned long pmsg_size; + unsigned long console_size; psz_read_op read; psz_write_op write; psz_write_op panic_write; -- 2.20.1
