summaryrefslogtreecommitdiff
path: root/fs/pstore/zone.c
diff options
context:
space:
mode:
authorWeiXiong Liao <liaoweixiong@allwinnertech.com>2020-03-25 11:55:00 +0300
committerKees Cook <keescook@chromium.org>2020-05-30 20:34:03 +0300
commitcc9c4d1b5597167f8e8c92f6b61e1cda6d01884d (patch)
treee85923479c50fbc727359bd5add5bfd5581ab040 /fs/pstore/zone.c
parent0dc068265a1c5923ffebf40388fbe93050a77ad1 (diff)
downloadlinux-cc9c4d1b5597167f8e8c92f6b61e1cda6d01884d.tar.xz
pstore/zone,blk: Add console frontend support
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 <liaoweixiong@allwinnertech.com> Link: https://lore.kernel.org/lkml/20200511233229.27745-5-keescook@chromium.org/ Signed-off-by: Kees Cook <keescook@chromium.org>
Diffstat (limited to 'fs/pstore/zone.c')
-rw-r--r--fs/pstore/zone.c81
1 files changed, 76 insertions, 5 deletions
diff --git a/fs/pstore/zone.c b/fs/pstore/zone.c
index 2f8e3b349edb..ee0b64da410d 100644
--- a/fs/pstore/zone.c
+++ b/fs/pstore/zone.c
@@ -91,10 +91,12 @@ struct pstore_zone {
*
* @kpszs: kmsg dump storage zones
* @ppsz: pmsg storage zone
+ * @cpsz: console storage zone
* @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
* @oops_counter: counter of oops dumps
* @panic_counter: counter of panic dumps
* @recovered: whether finished recovering data from storage
@@ -106,10 +108,12 @@ struct pstore_zone {
struct psz_context {
struct pstore_zone **kpszs;
struct pstore_zone *ppsz;
+ struct pstore_zone *cpsz;
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;
/*
* These counters should be calculated during recovery.
* It records the oops/panic times after crashes rather than boots.
@@ -129,6 +133,9 @@ struct psz_context {
};
static struct psz_context pstore_zone_cxt;
+static void psz_flush_all_dirty_zones(struct work_struct *);
+static DECLARE_DELAYED_WORK(psz_cleaner, psz_flush_all_dirty_zones);
+
/**
* enum psz_flush_mode - flush mode for psz_zone_write()
*
@@ -237,6 +244,9 @@ 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_delayed_work(&psz_cleaner, msecs_to_jiffies(500));
return -EBUSY;
}
@@ -293,6 +303,21 @@ 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 = &pstore_zone_cxt;
+ int ret = 0;
+
+ if (cxt->ppsz)
+ ret |= psz_flush_dirty_zone(cxt->ppsz);
+ if (cxt->cpsz)
+ ret |= psz_flush_dirty_zone(cxt->cpsz);
+ if (cxt->kpszs)
+ ret |= psz_flush_dirty_zones(cxt->kpszs, cxt->kmsg_max_cnt);
+ if (ret && cxt->pstore_zone_info)
+ schedule_delayed_work(&psz_cleaner, msecs_to_jiffies(1000));
+}
+
static int psz_kmsg_recover_data(struct psz_context *cxt)
{
struct pstore_zone_info *info = cxt->pstore_zone_info;
@@ -545,6 +570,10 @@ static inline int psz_recovery(struct psz_context *cxt)
goto out;
ret = psz_recover_zone(cxt, cxt->ppsz);
+ if (ret)
+ goto out;
+
+ ret = psz_recover_zone(cxt, cxt->cpsz);
out:
if (unlikely(ret))
@@ -562,6 +591,7 @@ static int psz_pstore_open(struct pstore_info *psi)
cxt->kmsg_read_cnt = 0;
cxt->pmsg_read_cnt = 0;
+ cxt->console_read_cnt = 0;
return 0;
}
@@ -626,8 +656,9 @@ static int psz_pstore_erase(struct pstore_record *record)
return psz_kmsg_erase(cxt, cxt->kpszs[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;
}
}
@@ -690,9 +721,10 @@ static int notrace psz_kmsg_write(struct psz_context *cxt,
return -ENOSPC;
ret = psz_kmsg_write_record(cxt, record);
- if (!ret) {
+ if (!ret && is_on_panic()) {
+ /* ensure all data are flushed to storage when panic */
pr_debug("try to flush other dirty zones\n");
- psz_flush_dirty_zones(cxt->kpszs, cxt->kmsg_max_cnt);
+ psz_flush_all_dirty_zones(NULL);
}
/* always return 0 as we had handled it on buffer */
@@ -756,9 +788,18 @@ 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_kmsg_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:
@@ -783,6 +824,13 @@ 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;
}
@@ -893,6 +941,8 @@ next_zone:
readop = psz_kmsg_read;
record->id = cxt->kmsg_read_cnt - 1;
break;
+ case PSTORE_TYPE_CONSOLE:
+ fallthrough;
case PSTORE_TYPE_PMSG:
readop = psz_record_read;
break;
@@ -953,6 +1003,8 @@ static void psz_free_all_zones(struct psz_context *cxt)
psz_free_zones(&cxt->kpszs, &cxt->kmsg_max_cnt);
if (cxt->ppsz)
psz_free_zone(&cxt->ppsz);
+ if (cxt->cpsz)
+ psz_free_zone(&cxt->cpsz);
}
static struct pstore_zone *psz_init_zone(enum pstore_type_id type,
@@ -1054,6 +1106,15 @@ 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);
+ cxt->cpsz = 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);
@@ -1088,7 +1149,7 @@ 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 record size must be non-zero\n");
return -EINVAL;
}
@@ -1111,6 +1172,7 @@ 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
@@ -1137,6 +1199,7 @@ int register_pstore_zone(struct pstore_zone_info *info)
pr_debug("\ttotal size : %ld Bytes\n", info->total_size);
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);
err = psz_alloc_zones(cxt);
if (err) {
@@ -1170,6 +1233,10 @@ 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);
@@ -1211,6 +1278,10 @@ void unregister_pstore_zone(struct pstore_zone_info *info)
/* Stop incoming writes from pstore. */
pstore_unregister(&cxt->pstore);
+ /* Flush any pending writes. */
+ psz_flush_all_dirty_zones(NULL);
+ flush_delayed_work(&psz_cleaner);
+
/* Clean up allocations. */
kfree(cxt->pstore.buf);
cxt->pstore.buf = NULL;