diff options
author | Dan Williams <dan.j.williams@intel.com> | 2007-11-14 16:59:35 -0800 |
---|---|---|
committer | Linus Torvalds <torvalds@woody.linux-foundation.org> | 2007-11-14 18:45:39 -0800 |
commit | 6c55be8b962f1bdc592d579e81fc27b11ea53dfc (patch) | |
tree | 3413cc2c8e26afdbc498cbdbd96bc2fa9733b2a6 /drivers/md | |
parent | 5b23dbe8173c212d6a326e35347b038705603d39 (diff) | |
download | kernel_samsung_smdk4412-6c55be8b962f1bdc592d579e81fc27b11ea53dfc.zip kernel_samsung_smdk4412-6c55be8b962f1bdc592d579e81fc27b11ea53dfc.tar.gz kernel_samsung_smdk4412-6c55be8b962f1bdc592d579e81fc27b11ea53dfc.tar.bz2 |
raid5: fix unending write sequence
<debug output from Joel's system>
handling stripe 7629696, state=0x14 cnt=1, pd_idx=2 ops=0:0:0
check 5: state 0x6 toread 0000000000000000 read 0000000000000000 write fffff800ffcffcc0 written 0000000000000000
check 4: state 0x6 toread 0000000000000000 read 0000000000000000 write fffff800fdd4e360 written 0000000000000000
check 3: state 0x1 toread 0000000000000000 read 0000000000000000 write 0000000000000000 written 0000000000000000
check 2: state 0x1 toread 0000000000000000 read 0000000000000000 write 0000000000000000 written 0000000000000000
check 1: state 0x6 toread 0000000000000000 read 0000000000000000 write fffff800ff517e40 written 0000000000000000
check 0: state 0x6 toread 0000000000000000 read 0000000000000000 write fffff800fd4cae60 written 0000000000000000
locked=4 uptodate=2 to_read=0 to_write=4 failed=0 failed_num=0
for sector 7629696, rmw=0 rcw=0
</debug>
These blocks were prepared to be written out, but were never handled in
ops_run_biodrain(), so they remain locked forever. The operations flags
are all clear which means handle_stripe() thinks nothing else needs to be
done.
This state suggests that the STRIPE_OP_PREXOR bit was sampled 'set' when it
should not have been. This patch cleans up cases where the code looks at
sh->ops.pending when it should be looking at the consistent stack-based
snapshot of the operations flags.
Report from Joel:
Resync done. Patch fix this bug.
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Tested-by: Joel Bertrand <joel.bertrand@systella.fr>
Cc: <stable@kernel.org>
Cc: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'drivers/md')
-rw-r--r-- | drivers/md/raid5.c | 16 |
1 files changed, 9 insertions, 7 deletions
diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c index 1cfc984..a5aad8c 100644 --- a/drivers/md/raid5.c +++ b/drivers/md/raid5.c @@ -688,7 +688,8 @@ ops_run_prexor(struct stripe_head *sh, struct dma_async_tx_descriptor *tx) } static struct dma_async_tx_descriptor * -ops_run_biodrain(struct stripe_head *sh, struct dma_async_tx_descriptor *tx) +ops_run_biodrain(struct stripe_head *sh, struct dma_async_tx_descriptor *tx, + unsigned long pending) { int disks = sh->disks; int pd_idx = sh->pd_idx, i; @@ -696,7 +697,7 @@ ops_run_biodrain(struct stripe_head *sh, struct dma_async_tx_descriptor *tx) /* check if prexor is active which means only process blocks * that are part of a read-modify-write (Wantprexor) */ - int prexor = test_bit(STRIPE_OP_PREXOR, &sh->ops.pending); + int prexor = test_bit(STRIPE_OP_PREXOR, &pending); pr_debug("%s: stripe %llu\n", __FUNCTION__, (unsigned long long)sh->sector); @@ -773,7 +774,8 @@ static void ops_complete_write(void *stripe_head_ref) } static void -ops_run_postxor(struct stripe_head *sh, struct dma_async_tx_descriptor *tx) +ops_run_postxor(struct stripe_head *sh, struct dma_async_tx_descriptor *tx, + unsigned long pending) { /* kernel stack size limits the total number of disks */ int disks = sh->disks; @@ -781,7 +783,7 @@ ops_run_postxor(struct stripe_head *sh, struct dma_async_tx_descriptor *tx) int count = 0, pd_idx = sh->pd_idx, i; struct page *xor_dest; - int prexor = test_bit(STRIPE_OP_PREXOR, &sh->ops.pending); + int prexor = test_bit(STRIPE_OP_PREXOR, &pending); unsigned long flags; dma_async_tx_callback callback; @@ -808,7 +810,7 @@ ops_run_postxor(struct stripe_head *sh, struct dma_async_tx_descriptor *tx) } /* check whether this postxor is part of a write */ - callback = test_bit(STRIPE_OP_BIODRAIN, &sh->ops.pending) ? + callback = test_bit(STRIPE_OP_BIODRAIN, &pending) ? ops_complete_write : ops_complete_postxor; /* 1/ if we prexor'd then the dest is reused as a source @@ -896,12 +898,12 @@ static void raid5_run_ops(struct stripe_head *sh, unsigned long pending) tx = ops_run_prexor(sh, tx); if (test_bit(STRIPE_OP_BIODRAIN, &pending)) { - tx = ops_run_biodrain(sh, tx); + tx = ops_run_biodrain(sh, tx, pending); overlap_clear++; } if (test_bit(STRIPE_OP_POSTXOR, &pending)) - ops_run_postxor(sh, tx); + ops_run_postxor(sh, tx, pending); if (test_bit(STRIPE_OP_CHECK, &pending)) ops_run_check(sh); |