From: WeiXiong Liao <liaoweixiong@xxxxxxxxxxxxxxxxx> Support backend for ftrace. To enable ftrace backend, just make ftrace_size be greater than 0 and a multiple of 4096. Signed-off-by: WeiXiong Liao <liaoweixiong@xxxxxxxxxxxxxxxxx> Link: https://lore.kernel.org/r/1585126506-18635-7-git-send-email-liaoweixiong@xxxxxxxxxxxxxxxxx Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx> --- fs/pstore/Kconfig | 12 ++++ fs/pstore/blk.c | 9 +++ fs/pstore/zone.c | 113 +++++++++++++++++++++++++++++++++++- include/linux/pstore_zone.h | 2 + 4 files changed, 135 insertions(+), 1 deletion(-) diff --git a/fs/pstore/Kconfig b/fs/pstore/Kconfig index 126aa6c3ecf2..c2237984b407 100644 --- a/fs/pstore/Kconfig +++ b/fs/pstore/Kconfig @@ -248,3 +248,15 @@ config PSTORE_BLK_CONSOLE_SIZE NOTE that, both Kconfig and module parameters can configure pstore/blk, but module parameters have priority over Kconfig. + +config PSTORE_BLK_FTRACE_SIZE + int "Size in Kbytes of ftrace log to store" + depends on PSTORE_BLK + depends on PSTORE_FTRACE + default 64 + help + This just sets size of ftrace log (ftrace_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 0b88c0bcd36c..9f1f0d5b3795 100644 --- a/fs/pstore/blk.c +++ b/fs/pstore/blk.c @@ -43,6 +43,14 @@ static long console_size = -1; module_param(console_size, long, 0400); MODULE_PARM_DESC(console_size, "console size in kbytes"); +#if IS_ENABLED(CONFIG_PSTORE_FTRACE) +static long ftrace_size = CONFIG_PSTORE_BLK_FTRACE_SIZE; +#else +static long ftrace_size = -1; +#endif +module_param(ftrace_size, long, 0400); +MODULE_PARM_DESC(ftrace_size, "ftrace size in kbytes"); + /* * blkdev - the block device to use for pstore storage * @@ -152,6 +160,7 @@ static int psblk_register_do(struct pstore_device_info *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); + verify_size(ftrace_size, 4096, dev->flags & PSTORE_FLAGS_FTRACE); #undef verify_size pstore_zone_info->total_size = dev->total_size; diff --git a/fs/pstore/zone.c b/fs/pstore/zone.c index 33c99dc5f980..d83b24f3cdd9 100644 --- a/fs/pstore/zone.c +++ b/fs/pstore/zone.c @@ -92,11 +92,14 @@ struct pstore_zone { * @kpszs: kmsg dump storage zones * @ppsz: pmsg storage zone * @cpsz: console storage zone + * @fpszs: ftrace storage zones * @kmsg_max_cnt: max count of @kpszs * @kmsg_read_cnt: counter of total read kmsg dumps * @kmsg_write_cnt: counter of total kmsg dump writes * @pmsg_read_cnt: counter of total read pmsg zone * @console_read_cnt: counter of total read console zone + * @ftrace_max_cnt: max count of @fpszs + * @ftrace_read_cnt: counter of max read ftrace zone * @oops_counter: counter of oops dumps * @panic_counter: counter of panic dumps * @recovered: whether finished recovering data from storage @@ -109,11 +112,14 @@ struct psz_context { struct pstore_zone **kpszs; struct pstore_zone *ppsz; struct pstore_zone *cpsz; + struct pstore_zone **fpszs; unsigned int kmsg_max_cnt; unsigned int kmsg_read_cnt; unsigned int kmsg_write_cnt; unsigned int pmsg_read_cnt; unsigned int console_read_cnt; + unsigned int ftrace_max_cnt; + unsigned int ftrace_read_cnt; /* * These counters should be calculated during recovery. * It records the oops/panic times after crashes rather than boots. @@ -314,6 +320,8 @@ static void psz_flush_all_dirty_zones(struct work_struct *work) ret |= psz_flush_dirty_zone(cxt->cpsz); if (cxt->kpszs) ret |= psz_flush_dirty_zones(cxt->kpszs, cxt->kmsg_max_cnt); + if (cxt->fpszs) + ret |= psz_flush_dirty_zones(cxt->fpszs, cxt->ftrace_max_cnt); if (ret && cxt->pstore_zone_info) schedule_delayed_work(&psz_cleaner, msecs_to_jiffies(1000)); } @@ -550,6 +558,31 @@ static int psz_recover_zone(struct psz_context *cxt, struct pstore_zone *zone) return ret; } +static int psz_recover_zones(struct psz_context *cxt, + struct pstore_zone **zones, unsigned int cnt) +{ + int ret; + unsigned int i; + struct pstore_zone *zone; + + if (!zones) + return 0; + + for (i = 0; i < cnt; i++) { + zone = zones[i]; + if (unlikely(!zone)) + continue; + ret = psz_recover_zone(cxt, zone); + if (ret) + goto recover_fail; + } + + return 0; +recover_fail: + pr_debug("recover %s[%u] failed\n", zone->name, i); + return ret; +} + /** * psz_recovery() - recover data from storage * @cxt: the context of pstore/zone @@ -577,6 +610,10 @@ static inline int psz_recovery(struct psz_context *cxt) if (ret) goto recover_fail; + ret = psz_recover_zones(cxt, cxt->fpszs, cxt->ftrace_max_cnt); + if (ret) + goto recover_fail; + pr_debug("recover end!\n"); atomic_set(&cxt->recovered, 1); return 0; @@ -593,6 +630,7 @@ static int psz_pstore_open(struct pstore_info *psi) cxt->kmsg_read_cnt = 0; cxt->pmsg_read_cnt = 0; cxt->console_read_cnt = 0; + cxt->ftrace_read_cnt = 0; return 0; } @@ -659,6 +697,10 @@ static int psz_pstore_erase(struct pstore_record *record) return psz_record_erase(cxt, cxt->ppsz); case PSTORE_TYPE_CONSOLE: return psz_record_erase(cxt, cxt->cpsz); + case PSTORE_TYPE_FTRACE: + if (record->id >= cxt->ftrace_max_cnt) + return -EINVAL; + return psz_record_erase(cxt, cxt->fpszs[record->id]); default: return -EINVAL; } } @@ -801,6 +843,13 @@ static int notrace psz_pstore_write(struct pstore_record *record) return psz_record_write(cxt->cpsz, record); case PSTORE_TYPE_PMSG: return psz_record_write(cxt->ppsz, record); + case PSTORE_TYPE_FTRACE: { + int zonenum = smp_processor_id(); + + if (!cxt->fpszs) + return -ENOSPC; + return psz_record_write(cxt->fpszs[zonenum], record); + } default: return -EINVAL; } @@ -816,6 +865,14 @@ static struct pstore_zone *psz_read_next_zone(struct psz_context *cxt) return zone; } + if (cxt->ftrace_read_cnt < cxt->ftrace_max_cnt) + /* + * No need psz_old_ok(). Let psz_ftrace_read() do so for + * combination. psz_ftrace_read() should traverse over + * all zones in case of some zone without data. + */ + return cxt->fpszs[cxt->ftrace_read_cnt++]; + if (cxt->pmsg_read_cnt == 0) { cxt->pmsg_read_cnt++; zone = cxt->ppsz; @@ -890,6 +947,37 @@ static ssize_t psz_kmsg_read(struct pstore_zone *zone, return size + hlen; } +/* try to combine all ftrace zones */ +static ssize_t psz_ftrace_read(struct pstore_zone *zone, + struct pstore_record *record) +{ + struct psz_context *cxt = record->psi->data; + struct psz_buffer *buf; + int ret; + + if (!zone || !record) + return -ENOSPC; + + if (!psz_old_ok(zone)) + goto out; + + buf = (struct psz_buffer *)zone->oldbuf; + if (!buf) + return -ENOMSG; + + ret = pstore_ftrace_combine_log(&record->buf, &record->size, + (char *)buf->data, atomic_read(&buf->datalen)); + if (unlikely(ret)) + return ret; + +out: + if (cxt->ftrace_read_cnt < cxt->ftrace_max_cnt) + /* then, read next ftrace zone */ + return -ENOMSG; + record->id = 0; + return record->size ? record->size : -ENOMSG; +} + static ssize_t psz_record_read(struct pstore_zone *zone, struct pstore_record *record) { @@ -940,6 +1028,9 @@ static ssize_t psz_pstore_read(struct pstore_record *record) readop = psz_kmsg_read; record->id = cxt->kmsg_read_cnt - 1; break; + case PSTORE_TYPE_FTRACE: + readop = psz_ftrace_read; + break; case PSTORE_TYPE_CONSOLE: fallthrough; case PSTORE_TYPE_PMSG: @@ -1004,6 +1095,8 @@ static void psz_free_all_zones(struct psz_context *cxt) psz_free_zone(&cxt->ppsz); if (cxt->cpsz) psz_free_zone(&cxt->cpsz); + if (cxt->fpszs) + psz_free_zones(&cxt->fpszs, &cxt->ftrace_max_cnt); } static struct pstore_zone *psz_init_zone(enum pstore_type_id type, @@ -1114,6 +1207,17 @@ static int psz_alloc_zones(struct psz_context *cxt) goto free_out; } + off_size += info->ftrace_size; + cxt->fpszs = psz_init_zones(PSTORE_TYPE_FTRACE, &off, + info->ftrace_size, + info->ftrace_size / nr_cpu_ids, + &cxt->ftrace_max_cnt); + if (IS_ERR(cxt->fpszs)) { + err = PTR_ERR(cxt->fpszs); + cxt->fpszs = NULL; + goto free_out; + } + cxt->kpszs = psz_init_zones(PSTORE_TYPE_DMESG, &off, info->total_size - off_size, info->kmsg_size, &cxt->kmsg_max_cnt); @@ -1148,7 +1252,8 @@ int register_pstore_zone(struct pstore_zone_info *info) return -EINVAL; } - if (!info->kmsg_size && !info->pmsg_size && !info->console_size) { + if (!info->kmsg_size && !info->pmsg_size && !info->console_size && + !info->ftrace_size) { pr_warn("at least one record size must be non-zero\n"); return -EINVAL; } @@ -1172,6 +1277,7 @@ int register_pstore_zone(struct pstore_zone_info *info) check_size(kmsg_size, SECTOR_SIZE); check_size(pmsg_size, SECTOR_SIZE); check_size(console_size, SECTOR_SIZE); + check_size(ftrace_size, SECTOR_SIZE); #undef check_size @@ -1199,6 +1305,7 @@ int register_pstore_zone(struct pstore_zone_info *info) pr_debug("\tkmsg 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); + pr_debug("\tftrace size : %ld Bytes\n", info->ftrace_size); err = psz_alloc_zones(cxt); if (err) { @@ -1236,6 +1343,10 @@ int register_pstore_zone(struct pstore_zone_info *info) cxt->pstore.flags |= PSTORE_FLAGS_CONSOLE; pr_cont(" console"); } + if (info->ftrace_size) { + cxt->pstore.flags |= PSTORE_FLAGS_FTRACE; + pr_cont(" ftrace"); + } pr_cont("\n"); err = pstore_register(&cxt->pstore); diff --git a/include/linux/pstore_zone.h b/include/linux/pstore_zone.h index 904ee67f4ba2..6f16b0dd834a 100644 --- a/include/linux/pstore_zone.h +++ b/include/linux/pstore_zone.h @@ -19,6 +19,7 @@ typedef ssize_t (*pstore_zone_write_op)(const char *, size_t, loff_t); * @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. + * @ftrace_size:The size of ftrace 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 @@ -37,6 +38,7 @@ struct pstore_zone_info { int max_reason; unsigned long pmsg_size; unsigned long console_size; + unsigned long ftrace_size; pstore_zone_read_op read; pstore_zone_write_op write; pstore_zone_write_op panic_write; -- 2.20.1
