[PATCH 1/8] btrfs: scrub: distinguish scrub_page from regular page

Qu Wenruo
2020-10-26T07:11:43Z

There are several call sites where we declare something like
"struct scrub_page *page".

This is just asking for troubles when read the code, as we also have
scrub_page::page member.

To avoid confusion, use "spage" for scrub_page strcture pointers.

Signed-off-by: Qu Wenruo <wqu@suse.com>
---
fs/btrfs/scrub.c | 102 +++++++++++++++++++++++------------------------
1 file changed, 51 insertions(+), 51 deletions(-)

diff --git a/fs/btrfs/scrub.c b/fs/btrfs/scrub.c
index 806523515d2f..0e25f9391b93 100644
--- a/fs/btrfs/scrub.c
+++ b/fs/btrfs/scrub.c
@@ -256,10 +256,10 @@ static void __scrub_blocked_if_needed(struct btrfs_fs_info *fs_info);
static void scrub_blocked_if_needed(struct btrfs_fs_info *fs_info);
static void scrub_put_ctx(struct scrub_ctx *sctx);

-static inline int scrub_is_page_on_raid56(struct scrub_page *page)
+static inline int scrub_is_page_on_raid56(struct scrub_page *spage)
{
- return page->recover &&
- (page->recover->bbio->map_type & BTRFS_BLOCK_GROUP_RAID56_MASK);
+ return spage->recover &&
+ (spage->recover->bbio->map_type & BTRFS_BLOCK_GROUP_RAID56_MASK);
}

static void scrub_pending_bio_inc(struct scrub_ctx *sctx)
@@ -1092,11 +1092,11 @@ static int scrub_handle_errored_block(struct scrub_block *sblock_to_check)
success = 1;
for (page_num = 0; page_num < sblock_bad->page_count;
page_num++) {
- struct scrub_page *page_bad = sblock_bad->pagev[page_num];
+ struct scrub_page *spage_bad = sblock_bad->pagev[page_num];
struct scrub_block *sblock_other = NULL;

/* skip no-io-error page in scrub */
- if (!page_bad->io_error && !sctx->is_dev_replace)
+ if (!spage_bad->io_error && !sctx->is_dev_replace)
continue;

if (scrub_is_page_on_raid56(sblock_bad->pagev[0])) {
@@ -1108,7 +1108,7 @@ static int scrub_handle_errored_block(struct scrub_block *sblock_to_check)
* sblock_for_recheck array to target device.
*/
sblock_other = NULL;
- } else if (page_bad->io_error) {
+ } else if (spage_bad->io_error) {
/* try to find no-io-error page in mirrors */
for (mirror_index = 0;
mirror_index < BTRFS_MAX_MIRRORS &&
@@ -1147,7 +1147,7 @@ static int scrub_handle_errored_block(struct scrub_block *sblock_to_check)
sblock_other,
page_num, 0);
if (0 == ret)
- page_bad->io_error = 0;
+ spage_bad->io_error = 0;
else
success = 0;
}
@@ -1325,13 +1325,13 @@ static int scrub_setup_recheck_block(struct scrub_block *original_sblock,
for (mirror_index = 0; mirror_index < nmirrors;
mirror_index++) {
struct scrub_block *sblock;
- struct scrub_page *page;
+ struct scrub_page *spage;

sblock = sblocks_for_recheck + mirror_index;
sblock->sctx = sctx;

- page = kzalloc(sizeof(*page), GFP_NOFS);
- if (!page) {
+ spage = kzalloc(sizeof(*spage), GFP_NOFS);
+ if (!spage) {
leave_nomem:
spin_lock(&sctx->stat_lock);
sctx->stat.malloc_errors++;
@@ -1339,15 +1339,15 @@ static int scrub_setup_recheck_block(struct scrub_block *original_sblock,
scrub_put_recover(fs_info, recover);
return -ENOMEM;
}
- scrub_page_get(page);
- sblock->pagev[page_index] = page;
- page->sblock = sblock;
- page->flags = flags;
- page->generation = generation;
- page->logical = logical;
- page->have_csum = have_csum;
+ scrub_page_get(spage);
+ sblock->pagev[page_index] = spage;
+ spage->sblock = sblock;
+ spage->flags = flags;
+ spage->generation = generation;
+ spage->logical = logical;
+ spage->have_csum = have_csum;
if (have_csum)
- memcpy(page->csum,
+ memcpy(spage->csum,
original_sblock->pagev[0]->csum,
sctx->csum_size);

@@ -1360,23 +1360,23 @@ static int scrub_setup_recheck_block(struct scrub_block *original_sblock,
mirror_index,
&stripe_index,
&stripe_offset);
- page->physical = bbio->stripes[stripe_index].physical +
+ spage->physical = bbio->stripes[stripe_index].physical +
stripe_offset;
- page->dev = bbio->stripes[stripe_index].dev;
+ spage->dev = bbio->stripes[stripe_index].dev;

BUG_ON(page_index >= original_sblock->page_count);
- page->physical_for_dev_replace =
+ spage->physical_for_dev_replace =
original_sblock->pagev[page_index]->
physical_for_dev_replace;
/* for missing devices, dev->bdev is NULL */
- page->mirror_num = mirror_index + 1;
+ spage->mirror_num = mirror_index + 1;
sblock->page_count++;
- page->page = alloc_page(GFP_NOFS);
- if (!page->page)
+ spage->page = alloc_page(GFP_NOFS);
+ if (!spage->page)
goto leave_nomem;

scrub_get_recover(recover);
- page->recover = recover;
+ spage->recover = recover;
}
scrub_put_recover(fs_info, recover);
length -= sublen;
@@ -1394,19 +1394,19 @@ static void scrub_bio_wait_endio(struct bio *bio)

static int scrub_submit_raid56_bio_wait(struct btrfs_fs_info *fs_info,
struct bio *bio,
- struct scrub_page *page)
+ struct scrub_page *spage)
{
DECLARE_COMPLETION_ONSTACK(done);
int ret;
int mirror_num;

- bio->bi_iter.bi_sector = page->logical >> 9;
+ bio->bi_iter.bi_sector = spage->logical >> 9;
bio->bi_private = &done;
bio->bi_end_io = scrub_bio_wait_endio;

- mirror_num = page->sblock->pagev[0]->mirror_num;
- ret = raid56_parity_recover(fs_info, bio, page->recover->bbio,
- page->recover->map_length,
+ mirror_num = spage->sblock->pagev[0]->mirror_num;
+ ret = raid56_parity_recover(fs_info, bio, spage->recover->bbio,
+ spage->recover->map_length,
mirror_num, 0);
if (ret)
return ret;
@@ -1431,10 +1431,10 @@ static void scrub_recheck_block_on_raid56(struct btrfs_fs_info *fs_info,
bio_set_dev(bio, first_page->dev->bdev);

for (page_num = 0; page_num < sblock->page_count; page_num++) {
- struct scrub_page *page = sblock->pagev[page_num];
+ struct scrub_page *spage = sblock->pagev[page_num];

- WARN_ON(!page->page);
- bio_add_page(bio, page->page, PAGE_SIZE, 0);
+ WARN_ON(!spage->page);
+ bio_add_page(bio, spage->page, PAGE_SIZE, 0);
}

if (scrub_submit_raid56_bio_wait(fs_info, bio, first_page)) {
@@ -1475,24 +1475,24 @@ static void scrub_recheck_block(struct btrfs_fs_info *fs_info,

for (page_num = 0; page_num < sblock->page_count; page_num++) {
struct bio *bio;
- struct scrub_page *page = sblock->pagev[page_num];
+ struct scrub_page *spage = sblock->pagev[page_num];

- if (page->dev->bdev == NULL) {
- page->io_error = 1;
+ if (spage->dev->bdev == NULL) {
+ spage->io_error = 1;
sblock->no_io_error_seen = 0;
continue;
}

- WARN_ON(!page->page);
+ WARN_ON(!spage->page);
bio = btrfs_io_bio_alloc(1);
- bio_set_dev(bio, page->dev->bdev);
+ bio_set_dev(bio, spage->dev->bdev);

- bio_add_page(bio, page->page, PAGE_SIZE, 0);
- bio->bi_iter.bi_sector = page->physical >> 9;
+ bio_add_page(bio, spage->page, PAGE_SIZE, 0);
+ bio->bi_iter.bi_sector = spage->physical >> 9;
bio->bi_opf = REQ_OP_READ;

if (btrfsic_submit_bio_wait(bio)) {
- page->io_error = 1;
+ spage->io_error = 1;
sblock->no_io_error_seen = 0;
}

@@ -1548,36 +1548,36 @@ static int scrub_repair_page_from_good_copy(struct scrub_block *sblock_bad,
struct scrub_block *sblock_good,
int page_num, int force_write)
{
- struct scrub_page *page_bad = sblock_bad->pagev[page_num];
- struct scrub_page *page_good = sblock_good->pagev[page_num];
+ struct scrub_page *spage_bad = sblock_bad->pagev[page_num];
+ struct scrub_page *spage_good = sblock_good->pagev[page_num];
struct btrfs_fs_info *fs_info = sblock_bad->sctx->fs_info;

- BUG_ON(page_bad->page == NULL);
- BUG_ON(page_good->page == NULL);
+ BUG_ON(spage_bad->page == NULL);
+ BUG_ON(spage_good->page == NULL);
if (force_write || sblock_bad->header_error ||
- sblock_bad->checksum_error || page_bad->io_error) {
+ sblock_bad->checksum_error || spage_bad->io_error) {
struct bio *bio;
int ret;

- if (!page_bad->dev->bdev) {
+ if (!spage_bad->dev->bdev) {
btrfs_warn_rl(fs_info,
"scrub_repair_page_from_good_copy(bdev == NULL) is unexpected");
return -EIO;
}

bio = btrfs_io_bio_alloc(1);
- bio_set_dev(bio, page_bad->dev->bdev);
- bio->bi_iter.bi_sector = page_bad->physical >> 9;
+ bio_set_dev(bio, spage_bad->dev->bdev);
+ bio->bi_iter.bi_sector = spage_bad->physical >> 9;
bio->bi_opf = REQ_OP_WRITE;

- ret = bio_add_page(bio, page_good->page, PAGE_SIZE, 0);
+ ret = bio_add_page(bio, spage_good->page, PAGE_SIZE, 0);
if (PAGE_SIZE != ret) {
bio_put(bio);
return -EIO;
}

if (btrfsic_submit_bio_wait(bio)) {
- btrfs_dev_stat_inc_and_print(page_bad->dev,
+ btrfs_dev_stat_inc_and_print(spage_bad->dev,
BTRFS_DEV_STAT_WRITE_ERRS);
atomic64_inc(&fs_info->dev_replace.num_write_errors);
bio_put(bio);
--
2.29.0