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btrfs: Fix calculate typo caused by ambiguous meaning of logic_end

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For example, in scrub_raid56_parity(), following lines are used
to judge is all data processed:
 place1: if (key.objectid > logic_end) ...
 place2: if (logic_start >= logic_end) ...
 ...
 (place2 is typo, is should be ">", it is copied from other
  place, where logic_end's meaning is different, long story...)

We can fix above typo directly, but the root reason is ambiguous
meaning of logic_end in scrub raid56 parity.

In other place, XXX_end is pointed to data which is not included,
and we need to process segment of [XXX_start, XXX_end).

But for scrub raid56 parity, logic_end is pointed to lattest data
need to process, and introduced many "+ 1" and "- 1" in code as
below:
 length = sparity->logic_end - sparity->logic_start + 1
 logic_end - logic_start + 1
 stripe_logical + increment - 1

This patch changed logic_end's meaning to make it in normal understanding
in raid56 parity functions and data struct alone with above bugfix.

Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
This commit is contained in:
Zhao Lei 2015-07-21 15:42:26 +08:00 committed by Chris Mason
parent 6fa96d72f7
commit a0dd59de3c
1 changed files with 5 additions and 5 deletions
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10
fs/btrfs/scrub.c
View file

@ -2702,7 +2702,7 @@ static void scrub_parity_check_and_repair(struct scrub_parity *sparity)
sparity->nsectors))
goto out;
length = sparity->logic_end - sparity->logic_start + 1;
length = sparity->logic_end - sparity->logic_start;
ret = btrfs_map_sblock(sctx->dev_root->fs_info, WRITE,
sparity->logic_start,
&length, &bbio, 0, 1);
@ -2868,7 +2868,7 @@ static noinline_for_stack int scrub_raid56_parity(struct scrub_ctx *sctx,
key.type != BTRFS_METADATA_ITEM_KEY)
goto next;
if (key.objectid > logic_end) {
if (key.objectid >= logic_end) {
stop_loop = 1;
break;
}
@ -2958,7 +2958,7 @@ static noinline_for_stack int scrub_raid56_parity(struct scrub_ctx *sctx,
out:
if (ret < 0)
scrub_parity_mark_sectors_error(sparity, logic_start,
logic_end - logic_start + 1);
logic_end - logic_start);
scrub_parity_put(sparity);
scrub_submit(sctx);
mutex_lock(&sctx->wr_ctx.wr_lock);
@ -3139,7 +3139,7 @@ static noinline_for_stack int scrub_stripe(struct scrub_ctx *sctx,
logical += base;
if (ret) {
stripe_logical += base;
stripe_end = stripe_logical + increment - 1;
stripe_end = stripe_logical + increment;
ret = scrub_raid56_parity(sctx, map, scrub_dev,
ppath, stripe_logical,
stripe_end);
@ -3287,7 +3287,7 @@ static noinline_for_stack int scrub_stripe(struct scrub_ctx *sctx,
if (ret && physical < physical_end) {
stripe_logical += base;
stripe_end = stripe_logical +
increment - 1;
increment;
ret = scrub_raid56_parity(sctx,
map, scrub_dev, ppath,
stripe_logical,