* [PATCH 1/5] bcache: fix memory corruption in bch_cache_accounting_clear()
2020-02-01 14:42 [PATCH 0/5] bcache patches for Linux v5.6-rc1 Coly Li
@ 2020-02-01 14:42 ` Coly Li
2020-02-01 14:42 ` [PATCH 2/5] bcache: explicity type cast in bset_bkey_last() Coly Li
` (4 subsequent siblings)
5 siblings, 0 replies; 7+ messages in thread
From: Coly Li @ 2020-02-01 14:42 UTC (permalink / raw)
To: axboe; +Cc: linux-bcache, linux-block, Coly Li
Commit 83ff9318c44ba ("bcache: not use hard coded memset size in
bch_cache_accounting_clear()") tries to make the code more easy to
understand by removing the hard coded number with following change,
void bch_cache_accounting_clear(...)
{
memset(&acc->total.cache_hits,
0,
- sizeof(unsigned long) * 7);
+ sizeof(struct cache_stats));
}
Unfortunately the change was wrong (it also tells us the original code
was not easy to correctly understand). The hard coded number 7 is used
because in struct cache_stats,
15 struct cache_stats {
16 struct kobject kobj;
17
18 unsigned long cache_hits;
19 unsigned long cache_misses;
20 unsigned long cache_bypass_hits;
21 unsigned long cache_bypass_misses;
22 unsigned long cache_readaheads;
23 unsigned long cache_miss_collisions;
24 unsigned long sectors_bypassed;
25
26 unsigned int rescale;
27 };
only members in LINE 18-24 want to be set to 0. It is wrong to use
'sizeof(struct cache_stats)' to replace 'sizeof(unsigned long) * 7), the
memory objects behind acc->total is staled by this change.
Сорокин Артем Сергеевич reports that by the following steps, kernel
panic will be triggered,
1. Create new set: make-bcache -B /dev/nvme1n1 -C /dev/sda --wipe-bcache
2. Run in /sys/fs/bcache/<uuid>:
echo 1 > clear_stats && cat stats_five_minute/cache_bypass_hits
I can reproduce the panic and get following dmesg with KASAN enabled,
[22613.172742] ==================================================================
[22613.172862] BUG: KASAN: null-ptr-deref in sysfs_kf_seq_show+0x117/0x230
[22613.172864] Read of size 8 at addr 0000000000000000 by task cat/6753
[22613.172870] CPU: 1 PID: 6753 Comm: cat Not tainted 5.5.0-rc7-lp151.28.16-default+ #11
[22613.172872] Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 07/29/2019
[22613.172873] Call Trace:
[22613.172964] dump_stack+0x8b/0xbb
[22613.172968] ? sysfs_kf_seq_show+0x117/0x230
[22613.172970] ? sysfs_kf_seq_show+0x117/0x230
[22613.173031] __kasan_report+0x176/0x192
[22613.173064] ? pr_cont_kernfs_name+0x40/0x60
[22613.173067] ? sysfs_kf_seq_show+0x117/0x230
[22613.173070] kasan_report+0xe/0x20
[22613.173072] sysfs_kf_seq_show+0x117/0x230
[22613.173105] seq_read+0x199/0x6d0
[22613.173110] vfs_read+0xa5/0x1a0
[22613.173113] ksys_read+0x110/0x160
[22613.173115] ? kernel_write+0xb0/0xb0
[22613.173177] do_syscall_64+0x77/0x290
[22613.173238] entry_SYSCALL_64_after_hwframe+0x44/0xa9
[22613.173241] RIP: 0033:0x7fc2c886ac61
[22613.173244] Code: fe ff ff 48 8d 3d c7 a0 09 00 48 83 ec 08 e8 46 03 02 00 66 0f 1f 44 00 00 8b 05 ca fb 2c 00 48 63 ff 85 c0 75 13 31 c0 0f 05 <48> 3d 00 f0 ff ff 77 57 f3 c3 0f 1f 44 00 00 55 53 48 89 d5 48 89
[22613.173245] RSP: 002b:00007ffebe776d68 EFLAGS: 00000246 ORIG_RAX: 0000000000000000
[22613.173248] RAX: ffffffffffffffda RBX: 0000000000020000 RCX: 00007fc2c886ac61
[22613.173249] RDX: 0000000000020000 RSI: 00007fc2c8cca000 RDI: 0000000000000003
[22613.173250] RBP: 0000000000020000 R08: ffffffffffffffff R09: 0000000000000000
[22613.173251] R10: 000000000000038c R11: 0000000000000246 R12: 00007fc2c8cca000
[22613.173253] R13: 0000000000000003 R14: 00007fc2c8cca00f R15: 0000000000020000
[22613.173255] ==================================================================
[22613.173256] Disabling lock debugging due to kernel taint
[22613.173350] BUG: kernel NULL pointer dereference, address: 0000000000000000
[22613.178380] #PF: supervisor read access in kernel mode
[22613.180959] #PF: error_code(0x0000) - not-present page
[22613.183444] PGD 0 P4D 0
[22613.184867] Oops: 0000 [#1] SMP KASAN PTI
[22613.186797] CPU: 1 PID: 6753 Comm: cat Tainted: G B 5.5.0-rc7-lp151.28.16-default+ #11
[22613.191253] Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 07/29/2019
[22613.196706] RIP: 0010:sysfs_kf_seq_show+0x117/0x230
[22613.199097] Code: ff 48 8b 0b 48 8b 44 24 08 48 01 e9 eb a6 31 f6 48 89 cf ba 00 10 00 00 48 89 4c 24 10 e8 b1 e6 e9 ff 4c 89 ff e8 19 07 ea ff <49> 8b 07 48 85 c0 48 89 44 24 08 0f 84 91 00 00 00 49 8b 6d 00 48
[22613.208016] RSP: 0018:ffff8881d4f8fd78 EFLAGS: 00010246
[22613.210448] RAX: 0000000000000000 RBX: ffff8881eb99b180 RCX: ffffffff810d9ef6
[22613.213691] RDX: 0000000000000001 RSI: 0000000000000246 RDI: 0000000000000246
[22613.216893] RBP: 0000000000001000 R08: fffffbfff072ddcd R09: fffffbfff072ddcd
[22613.220075] R10: 0000000000000001 R11: fffffbfff072ddcc R12: ffff8881de5c0200
[22613.223256] R13: ffff8881ed175500 R14: ffff8881eb99b198 R15: 0000000000000000
[22613.226290] FS: 00007fc2c8d3d500(0000) GS:ffff8881f2a80000(0000) knlGS:0000000000000000
[22613.229637] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[22613.231993] CR2: 0000000000000000 CR3: 00000001ec89a004 CR4: 00000000003606e0
[22613.234909] Call Trace:
[22613.235931] seq_read+0x199/0x6d0
[22613.237259] vfs_read+0xa5/0x1a0
[22613.239229] ksys_read+0x110/0x160
[22613.240590] ? kernel_write+0xb0/0xb0
[22613.242040] do_syscall_64+0x77/0x290
[22613.243625] entry_SYSCALL_64_after_hwframe+0x44/0xa9
[22613.245450] RIP: 0033:0x7fc2c886ac61
[22613.246706] Code: fe ff ff 48 8d 3d c7 a0 09 00 48 83 ec 08 e8 46 03 02 00 66 0f 1f 44 00 00 8b 05 ca fb 2c 00 48 63 ff 85 c0 75 13 31 c0 0f 05 <48> 3d 00 f0 ff ff 77 57 f3 c3 0f 1f 44 00 00 55 53 48 89 d5 48 89
[22613.253296] RSP: 002b:00007ffebe776d68 EFLAGS: 00000246 ORIG_RAX: 0000000000000000
[22613.255835] RAX: ffffffffffffffda RBX: 0000000000020000 RCX: 00007fc2c886ac61
[22613.258472] RDX: 0000000000020000 RSI: 00007fc2c8cca000 RDI: 0000000000000003
[22613.260807] RBP: 0000000000020000 R08: ffffffffffffffff R09: 0000000000000000
[22613.263188] R10: 000000000000038c R11: 0000000000000246 R12: 00007fc2c8cca000
[22613.265598] R13: 0000000000000003 R14: 00007fc2c8cca00f R15: 0000000000020000
[22613.268729] Modules linked in: scsi_transport_iscsi af_packet iscsi_ibft iscsi_boot_sysfs vmw_vsock_vmci_transport vsock fuse bnep kvm_intel kvm irqbypass crc32_pclmul crc32c_intel ghash_clmulni_intel snd_ens1371 snd_ac97_codec ac97_bus bcache snd_pcm btusb btrtl btbcm btintel crc64 aesni_intel glue_helper crypto_simd vmw_balloon cryptd bluetooth snd_timer snd_rawmidi snd joydev pcspkr e1000 rfkill vmw_vmci soundcore ecdh_generic ecc gameport i2c_piix4 mptctl ac button hid_generic usbhid sr_mod cdrom ata_generic ehci_pci vmwgfx uhci_hcd drm_kms_helper syscopyarea serio_raw sysfillrect sysimgblt fb_sys_fops ttm ehci_hcd mptspi scsi_transport_spi mptscsih ata_piix mptbase ahci usbcore libahci drm sg dm_multipath dm_mod scsi_dh_rdac scsi_dh_emc scsi_dh_alua
[22613.292429] CR2: 0000000000000000
[22613.293563] ---[ end trace a074b26a8508f378 ]---
[22613.295138] RIP: 0010:sysfs_kf_seq_show+0x117/0x230
[22613.296769] Code: ff 48 8b 0b 48 8b 44 24 08 48 01 e9 eb a6 31 f6 48 89 cf ba 00 10 00 00 48 89 4c 24 10 e8 b1 e6 e9 ff 4c 89 ff e8 19 07 ea ff <49> 8b 07 48 85 c0 48 89 44 24 08 0f 84 91 00 00 00 49 8b 6d 00 48
[22613.303553] RSP: 0018:ffff8881d4f8fd78 EFLAGS: 00010246
[22613.305280] RAX: 0000000000000000 RBX: ffff8881eb99b180 RCX: ffffffff810d9ef6
[22613.307924] RDX: 0000000000000001 RSI: 0000000000000246 RDI: 0000000000000246
[22613.310272] RBP: 0000000000001000 R08: fffffbfff072ddcd R09: fffffbfff072ddcd
[22613.312685] R10: 0000000000000001 R11: fffffbfff072ddcc R12: ffff8881de5c0200
[22613.315076] R13: ffff8881ed175500 R14: ffff8881eb99b198 R15: 0000000000000000
[22613.318116] FS: 00007fc2c8d3d500(0000) GS:ffff8881f2a80000(0000) knlGS:0000000000000000
[22613.320743] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[22613.322628] CR2: 0000000000000000 CR3: 00000001ec89a004 CR4: 00000000003606e0
Here this patch fixes the following problem by explicity set all the 7
members to 0 in bch_cache_accounting_clear().
Reported-by: Сорокин Артем Сергеевич <a.sorokin@bank-hlynov.ru>
Signed-off-by: Coly Li <colyli@suse.de>
---
drivers/md/bcache/stats.c | 10 +++++++---
1 file changed, 7 insertions(+), 3 deletions(-)
diff --git a/drivers/md/bcache/stats.c b/drivers/md/bcache/stats.c
index ba1c93791d8d..503aafe188dc 100644
--- a/drivers/md/bcache/stats.c
+++ b/drivers/md/bcache/stats.c
@@ -109,9 +109,13 @@ int bch_cache_accounting_add_kobjs(struct cache_accounting *acc,
void bch_cache_accounting_clear(struct cache_accounting *acc)
{
- memset(&acc->total.cache_hits,
- 0,
- sizeof(struct cache_stats));
+ acc->total.cache_hits = 0;
+ acc->total.cache_misses = 0;
+ acc->total.cache_bypass_hits = 0;
+ acc->total.cache_bypass_misses = 0;
+ acc->total.cache_readaheads = 0;
+ acc->total.cache_miss_collisions = 0;
+ acc->total.sectors_bypassed = 0;
}
void bch_cache_accounting_destroy(struct cache_accounting *acc)
--
2.16.4
^ permalink raw reply related [flat|nested] 7+ messages in thread* [PATCH 2/5] bcache: explicity type cast in bset_bkey_last()
2020-02-01 14:42 [PATCH 0/5] bcache patches for Linux v5.6-rc1 Coly Li
2020-02-01 14:42 ` [PATCH 1/5] bcache: fix memory corruption in bch_cache_accounting_clear() Coly Li
@ 2020-02-01 14:42 ` Coly Li
2020-02-01 14:42 ` [PATCH 3/5] bcache: add readahead cache policy options via sysfs interface Coly Li
` (3 subsequent siblings)
5 siblings, 0 replies; 7+ messages in thread
From: Coly Li @ 2020-02-01 14:42 UTC (permalink / raw)
To: axboe; +Cc: linux-bcache, linux-block, Coly Li
In bset.h, macro bset_bkey_last() is defined as,
bkey_idx((struct bkey *) (i)->d, (i)->keys)
Parameter i can be variable type of data structure, the macro always
works once the type of struct i has member 'd' and 'keys'.
bset_bkey_last() is also used in macro csum_set() to calculate the
checksum of a on-disk data structure. When csum_set() is used to
calculate checksum of on-disk bcache super block, the parameter 'i'
data type is struct cache_sb_disk. Inside struct cache_sb_disk (also in
struct cache_sb) the member keys is __u16 type. But bkey_idx() expects
unsigned int (a 32bit width), so there is problem when sending
parameters via stack to call bkey_idx().
Sparse tool from Intel 0day kbuild system reports this incompatible
problem. bkey_idx() is part of user space API, so the simplest fix is
to cast the (i)->keys to unsigned int type in macro bset_bkey_last().
Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Coly Li <colyli@suse.de>
---
drivers/md/bcache/bset.h | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/md/bcache/bset.h b/drivers/md/bcache/bset.h
index c71365e7c1fa..a50dcfda656f 100644
--- a/drivers/md/bcache/bset.h
+++ b/drivers/md/bcache/bset.h
@@ -397,7 +397,8 @@ void bch_btree_keys_stats(struct btree_keys *b, struct bset_stats *state);
/* Bkey utility code */
-#define bset_bkey_last(i) bkey_idx((struct bkey *) (i)->d, (i)->keys)
+#define bset_bkey_last(i) bkey_idx((struct bkey *) (i)->d, \
+ (unsigned int)(i)->keys)
static inline struct bkey *bset_bkey_idx(struct bset *i, unsigned int idx)
{
--
2.16.4
^ permalink raw reply related [flat|nested] 7+ messages in thread* [PATCH 3/5] bcache: add readahead cache policy options via sysfs interface
2020-02-01 14:42 [PATCH 0/5] bcache patches for Linux v5.6-rc1 Coly Li
2020-02-01 14:42 ` [PATCH 1/5] bcache: fix memory corruption in bch_cache_accounting_clear() Coly Li
2020-02-01 14:42 ` [PATCH 2/5] bcache: explicity type cast in bset_bkey_last() Coly Li
@ 2020-02-01 14:42 ` Coly Li
2020-02-01 14:42 ` [PATCH 4/5] bcache: fix incorrect data type usage in btree_flush_write() Coly Li
` (2 subsequent siblings)
5 siblings, 0 replies; 7+ messages in thread
From: Coly Li @ 2020-02-01 14:42 UTC (permalink / raw)
To: axboe; +Cc: linux-bcache, linux-block, Coly Li, stable, Michael Lyle
In year 2007 high performance SSD was still expensive, in order to
save more space for real workload or meta data, the readahead I/Os
for non-meta data was bypassed and not cached on SSD.
In now days, SSD price drops a lot and people can find larger size
SSD with more comfortable price. It is unncessary to alway bypass
normal readahead I/Os to save SSD space for now.
This patch adds options for readahead data cache policies via sysfs
file /sys/block/bcache<N>/readahead_cache_policy, the options are,
- "all": cache all readahead data I/Os.
- "meta-only": only cache meta data, and bypass other regular I/Os.
If users want to make bcache continue to only cache readahead request
for metadata and bypass regular data readahead, please set "meta-only"
to this sysfs file. By default, bcache will back to cache all read-
ahead requests now.
Cc: stable@vger.kernel.org
Signed-off-by: Coly Li <colyli@suse.de>
Acked-by: Eric Wheeler <bcache@linux.ewheeler.net>
Cc: Michael Lyle <mlyle@lyle.org>
---
drivers/md/bcache/bcache.h | 3 +++
drivers/md/bcache/request.c | 17 ++++++++++++-----
drivers/md/bcache/sysfs.c | 22 ++++++++++++++++++++++
3 files changed, 37 insertions(+), 5 deletions(-)
diff --git a/drivers/md/bcache/bcache.h b/drivers/md/bcache/bcache.h
index adf26a21fcd1..74a9849ea164 100644
--- a/drivers/md/bcache/bcache.h
+++ b/drivers/md/bcache/bcache.h
@@ -330,6 +330,9 @@ struct cached_dev {
*/
atomic_t has_dirty;
+#define BCH_CACHE_READA_ALL 0
+#define BCH_CACHE_READA_META_ONLY 1
+ unsigned int cache_readahead_policy;
struct bch_ratelimit writeback_rate;
struct delayed_work writeback_rate_update;
diff --git a/drivers/md/bcache/request.c b/drivers/md/bcache/request.c
index 73478a91a342..820d8402a1dc 100644
--- a/drivers/md/bcache/request.c
+++ b/drivers/md/bcache/request.c
@@ -379,13 +379,20 @@ static bool check_should_bypass(struct cached_dev *dc, struct bio *bio)
goto skip;
/*
- * Flag for bypass if the IO is for read-ahead or background,
- * unless the read-ahead request is for metadata
+ * If the bio is for read-ahead or background IO, bypass it or
+ * not depends on the following situations,
+ * - If the IO is for meta data, always cache it and no bypass
+ * - If the IO is not meta data, check dc->cache_reada_policy,
+ * BCH_CACHE_READA_ALL: cache it and not bypass
+ * BCH_CACHE_READA_META_ONLY: not cache it and bypass
+ * That is, read-ahead request for metadata always get cached
* (eg, for gfs2 or xfs).
*/
- if (bio->bi_opf & (REQ_RAHEAD|REQ_BACKGROUND) &&
- !(bio->bi_opf & (REQ_META|REQ_PRIO)))
- goto skip;
+ if ((bio->bi_opf & (REQ_RAHEAD|REQ_BACKGROUND))) {
+ if (!(bio->bi_opf & (REQ_META|REQ_PRIO)) &&
+ (dc->cache_readahead_policy != BCH_CACHE_READA_ALL))
+ goto skip;
+ }
if (bio->bi_iter.bi_sector & (c->sb.block_size - 1) ||
bio_sectors(bio) & (c->sb.block_size - 1)) {
diff --git a/drivers/md/bcache/sysfs.c b/drivers/md/bcache/sysfs.c
index 733e2ddf3c78..3470fae4eabc 100644
--- a/drivers/md/bcache/sysfs.c
+++ b/drivers/md/bcache/sysfs.c
@@ -27,6 +27,12 @@ static const char * const bch_cache_modes[] = {
NULL
};
+static const char * const bch_reada_cache_policies[] = {
+ "all",
+ "meta-only",
+ NULL
+};
+
/* Default is 0 ("auto") */
static const char * const bch_stop_on_failure_modes[] = {
"auto",
@@ -100,6 +106,7 @@ rw_attribute(congested_write_threshold_us);
rw_attribute(sequential_cutoff);
rw_attribute(data_csum);
rw_attribute(cache_mode);
+rw_attribute(readahead_cache_policy);
rw_attribute(stop_when_cache_set_failed);
rw_attribute(writeback_metadata);
rw_attribute(writeback_running);
@@ -168,6 +175,11 @@ SHOW(__bch_cached_dev)
bch_cache_modes,
BDEV_CACHE_MODE(&dc->sb));
+ if (attr == &sysfs_readahead_cache_policy)
+ return bch_snprint_string_list(buf, PAGE_SIZE,
+ bch_reada_cache_policies,
+ dc->cache_readahead_policy);
+
if (attr == &sysfs_stop_when_cache_set_failed)
return bch_snprint_string_list(buf, PAGE_SIZE,
bch_stop_on_failure_modes,
@@ -353,6 +365,15 @@ STORE(__cached_dev)
}
}
+ if (attr == &sysfs_readahead_cache_policy) {
+ v = __sysfs_match_string(bch_reada_cache_policies, -1, buf);
+ if (v < 0)
+ return v;
+
+ if ((unsigned int) v != dc->cache_readahead_policy)
+ dc->cache_readahead_policy = v;
+ }
+
if (attr == &sysfs_stop_when_cache_set_failed) {
v = __sysfs_match_string(bch_stop_on_failure_modes, -1, buf);
if (v < 0)
@@ -467,6 +488,7 @@ static struct attribute *bch_cached_dev_files[] = {
&sysfs_data_csum,
#endif
&sysfs_cache_mode,
+ &sysfs_readahead_cache_policy,
&sysfs_stop_when_cache_set_failed,
&sysfs_writeback_metadata,
&sysfs_writeback_running,
--
2.16.4
^ permalink raw reply related [flat|nested] 7+ messages in thread* [PATCH 4/5] bcache: fix incorrect data type usage in btree_flush_write()
2020-02-01 14:42 [PATCH 0/5] bcache patches for Linux v5.6-rc1 Coly Li
` (2 preceding siblings ...)
2020-02-01 14:42 ` [PATCH 3/5] bcache: add readahead cache policy options via sysfs interface Coly Li
@ 2020-02-01 14:42 ` Coly Li
2020-02-01 14:42 ` [PATCH 5/5] bcache: check return value of prio_read() Coly Li
2020-02-01 14:58 ` [PATCH 0/5] bcache patches for Linux v5.6-rc1 Jens Axboe
5 siblings, 0 replies; 7+ messages in thread
From: Coly Li @ 2020-02-01 14:42 UTC (permalink / raw)
To: axboe; +Cc: linux-bcache, linux-block, Coly Li
Dan Carpenter points out that from commit 2aa8c529387c ("bcache: avoid
unnecessary btree nodes flushing in btree_flush_write()"), there is a
incorrect data type usage which leads to the following static checker
warning:
drivers/md/bcache/journal.c:444 btree_flush_write()
warn: 'ref_nr' unsigned <= 0
drivers/md/bcache/journal.c
422 static void btree_flush_write(struct cache_set *c)
423 {
424 struct btree *b, *t, *btree_nodes[BTREE_FLUSH_NR];
425 unsigned int i, nr, ref_nr;
^^^^^^
426 atomic_t *fifo_front_p, *now_fifo_front_p;
427 size_t mask;
428
429 if (c->journal.btree_flushing)
430 return;
431
432 spin_lock(&c->journal.flush_write_lock);
433 if (c->journal.btree_flushing) {
434 spin_unlock(&c->journal.flush_write_lock);
435 return;
436 }
437 c->journal.btree_flushing = true;
438 spin_unlock(&c->journal.flush_write_lock);
439
440 /* get the oldest journal entry and check its refcount */
441 spin_lock(&c->journal.lock);
442 fifo_front_p = &fifo_front(&c->journal.pin);
443 ref_nr = atomic_read(fifo_front_p);
444 if (ref_nr <= 0) {
^^^^^^^^^^^
Unsigned can't be less than zero.
445 /*
446 * do nothing if no btree node references
447 * the oldest journal entry
448 */
449 spin_unlock(&c->journal.lock);
450 goto out;
451 }
452 spin_unlock(&c->journal.lock);
As the warning information indicates, local varaible ref_nr in unsigned
int type is wrong, which does not matche atomic_read() and the "<= 0"
checking.
This patch fixes the above error by defining local variable ref_nr as
int type.
Fixes: 2aa8c529387c ("bcache: avoid unnecessary btree nodes flushing in btree_flush_write()")
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Coly Li <colyli@suse.de>
---
drivers/md/bcache/journal.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/md/bcache/journal.c b/drivers/md/bcache/journal.c
index 33ddc5269e8d..6730820780b0 100644
--- a/drivers/md/bcache/journal.c
+++ b/drivers/md/bcache/journal.c
@@ -422,7 +422,8 @@ int bch_journal_replay(struct cache_set *s, struct list_head *list)
static void btree_flush_write(struct cache_set *c)
{
struct btree *b, *t, *btree_nodes[BTREE_FLUSH_NR];
- unsigned int i, nr, ref_nr;
+ unsigned int i, nr;
+ int ref_nr;
atomic_t *fifo_front_p, *now_fifo_front_p;
size_t mask;
--
2.16.4
^ permalink raw reply related [flat|nested] 7+ messages in thread* [PATCH 5/5] bcache: check return value of prio_read()
2020-02-01 14:42 [PATCH 0/5] bcache patches for Linux v5.6-rc1 Coly Li
` (3 preceding siblings ...)
2020-02-01 14:42 ` [PATCH 4/5] bcache: fix incorrect data type usage in btree_flush_write() Coly Li
@ 2020-02-01 14:42 ` Coly Li
2020-02-01 14:58 ` [PATCH 0/5] bcache patches for Linux v5.6-rc1 Jens Axboe
5 siblings, 0 replies; 7+ messages in thread
From: Coly Li @ 2020-02-01 14:42 UTC (permalink / raw)
To: axboe; +Cc: linux-bcache, linux-block, Coly Li
Now if prio_read() failed during starting a cache set, we can print
out error message in run_cache_set() and handle the failure properly.
Signed-off-by: Coly Li <colyli@suse.de>
---
drivers/md/bcache/super.c | 21 ++++++++++++++++-----
1 file changed, 16 insertions(+), 5 deletions(-)
diff --git a/drivers/md/bcache/super.c b/drivers/md/bcache/super.c
index 3dea1d5acd5c..2749daf09724 100644
--- a/drivers/md/bcache/super.c
+++ b/drivers/md/bcache/super.c
@@ -609,12 +609,13 @@ int bch_prio_write(struct cache *ca, bool wait)
return 0;
}
-static void prio_read(struct cache *ca, uint64_t bucket)
+static int prio_read(struct cache *ca, uint64_t bucket)
{
struct prio_set *p = ca->disk_buckets;
struct bucket_disk *d = p->data + prios_per_bucket(ca), *end = d;
struct bucket *b;
unsigned int bucket_nr = 0;
+ int ret = -EIO;
for (b = ca->buckets;
b < ca->buckets + ca->sb.nbuckets;
@@ -627,11 +628,15 @@ static void prio_read(struct cache *ca, uint64_t bucket)
prio_io(ca, bucket, REQ_OP_READ, 0);
if (p->csum !=
- bch_crc64(&p->magic, bucket_bytes(ca) - 8))
+ bch_crc64(&p->magic, bucket_bytes(ca) - 8)) {
pr_warn("bad csum reading priorities");
+ goto out;
+ }
- if (p->magic != pset_magic(&ca->sb))
+ if (p->magic != pset_magic(&ca->sb)) {
pr_warn("bad magic reading priorities");
+ goto out;
+ }
bucket = p->next_bucket;
d = p->data;
@@ -640,6 +645,10 @@ static void prio_read(struct cache *ca, uint64_t bucket)
b->prio = le16_to_cpu(d->prio);
b->gen = b->last_gc = d->gen;
}
+
+ ret = 0;
+out:
+ return ret;
}
/* Bcache device */
@@ -1873,8 +1882,10 @@ static int run_cache_set(struct cache_set *c)
j = &list_entry(journal.prev, struct journal_replay, list)->j;
err = "IO error reading priorities";
- for_each_cache(ca, c, i)
- prio_read(ca, j->prio_bucket[ca->sb.nr_this_dev]);
+ for_each_cache(ca, c, i) {
+ if (prio_read(ca, j->prio_bucket[ca->sb.nr_this_dev]))
+ goto err;
+ }
/*
* If prio_read() fails it'll call cache_set_error and we'll
--
2.16.4
^ permalink raw reply related [flat|nested] 7+ messages in thread* Re: [PATCH 0/5] bcache patches for Linux v5.6-rc1
2020-02-01 14:42 [PATCH 0/5] bcache patches for Linux v5.6-rc1 Coly Li
` (4 preceding siblings ...)
2020-02-01 14:42 ` [PATCH 5/5] bcache: check return value of prio_read() Coly Li
@ 2020-02-01 14:58 ` Jens Axboe
5 siblings, 0 replies; 7+ messages in thread
From: Jens Axboe @ 2020-02-01 14:58 UTC (permalink / raw)
To: Coly Li; +Cc: linux-bcache, linux-block
On 2/1/20 7:42 AM, Coly Li wrote:
> Hi Jens,
>
> Here are the bcache patches for Linux v5.6-rc1. All the patches are
> tested and survived my I/O pressure tests for 24+ hours intotal.
>
> Please take them. Thank you in advance.
Applied for 5.6, thanks.
--
Jens Axboe
^ permalink raw reply [flat|nested] 7+ messages in thread