pstore/zone,blk: Add ftrace frontend support

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@allwinnertech.com>
Link: https://lore.kernel.org/lkml/20200511233229.27745-6-keescook@chromium.org/
Co-developed-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Link: https://lore.kernel.org/lkml/20200512170719.221514-1-colin.king@canonical.com
Signed-off-by: Kees Cook <keescook@chromium.org>
This commit is contained in:
WeiXiong Liao 2020-03-25 16:55:01 +08:00 committed by Kees Cook
parent cc9c4d1b55
commit 34327e9fd2
4 changed files with 136 additions and 1 deletions

View File

@ -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.

View File

@ -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;

View File

@ -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 @@ free_oldbuf:
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
@ -574,6 +607,10 @@ static inline int psz_recovery(struct psz_context *cxt)
goto out;
ret = psz_recover_zone(cxt, cxt->cpsz);
if (ret)
goto out;
ret = psz_recover_zones(cxt, cxt->fpszs, cxt->ftrace_max_cnt);
out:
if (unlikely(ret))
@ -592,6 +629,7 @@ 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;
}
@ -658,6 +696,10 @@ 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;
}
}
@ -802,6 +844,13 @@ 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;
}
@ -817,6 +866,14 @@ 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;
@ -891,6 +948,38 @@ 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;
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:
cxt = record->psi->data;
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)
{
@ -941,6 +1030,9 @@ next_zone:
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:
@ -1005,6 +1097,8 @@ 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,
@ -1115,6 +1209,17 @@ 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);
@ -1149,7 +1254,8 @@ 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;
}
@ -1173,6 +1279,7 @@ 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
@ -1200,6 +1307,7 @@ 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) {
@ -1237,6 +1345,10 @@ 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);

View File

@ -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;