Skip to content

Commit

Permalink
bcachefs: fix initial page state after falloc
Browse files Browse the repository at this point in the history 
When initializing the page state, set the page sectors state to
that of what exists in the btree. This allows us to check if the
backing extent was already allocated before adding to the inode
i_blocks value.

Signed-off-by: Dan Robertson <[email protected]>
  • Loading branch information
@dlrobertson
dlrobertson committed Jun 27, 2021
1 parent 21578ad commit 3fe6e97
Showing 1 changed file with 112 additions and 19 deletions.
131 changes: 112 additions & 19 deletions fs/bcachefs/fs-io.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -291,9 +291,15 @@ static void bch2_page_state_release(struct page *page)
__bch2_page_state_release(page);
}

/* for newly allocated pages: */
static struct bch_page_state *__bch2_page_state_create(struct page *page,
gfp_t gfp)
/**
* __bch2_page_state_alloc - allocate the bcachefs page state
* @page: page to attach the bcachefs page state to
* @gfp: additional memory allocation flags
*
* Allocate the bcachefs page private data for the given page.
*/
static struct bch_page_state *__bch2_page_state_alloc(struct page *page,
gfp_t gfp)
{
struct bch_page_state *s;

Expand All @@ -306,10 +312,87 @@ static struct bch_page_state *__bch2_page_state_create(struct page *page,
return s;
}

static struct bch_page_state *bch2_page_state_create(struct page *page,
/**
* __bch2_page_state_create - internal create function for bcachefs page state
* @c: bcachefs filesystem of the backing sectors
* @page: page to attach the bcachefs page state to
* @gfp: additional memory allocation flags
*
* Allocate the bcachefs ptge private data for the given page and set the
* page state to that of the corresponding sectors in the btree.
*/
static struct bch_page_state *__bch2_page_state_create(struct bch_fs *c,
struct page *page,
gfp_t gfp)
{
struct bch_inode_info *inode = to_bch_ei(page->mapping->host);
struct bch_page_state *s;
struct btree_iter *iter;
struct btree_trans trans;
struct bkey_s_c k;
loff_t start = page->index << PAGE_SECTOR_SHIFT;
int i, ret;

s = __bch2_page_state_alloc(page, gfp);
if (!s)
return NULL;

/*
* Touching the btree can be expensive. We only want to touch
* the btree if the page is not uptodate and no page state
* currently exists.
*/
if (PageUptodate(page))
return s;

bch2_trans_init(&trans, c, BTREE_ITER_MAX, 0);

iter = bch2_trans_get_iter(&trans, BTREE_ID_extents,
POS(inode->v.i_ino, start),
BTREE_ITER_SLOTS | BTREE_ITER_INTENT);

ret = PTR_ERR_OR_ZERO(iter);

if (ret) {
kfree(s);
return NULL;
}

for (i = 0; i < PAGE_SECTORS; ++i) {
bch2_btree_iter_set_pos(iter, POS(inode->v.i_ino, start + i));
k = bch2_btree_iter_peek_slot(iter);
ret = bkey_err(k);

if (!ret && bkey_extent_is_allocation(k.k)) {
s->s[i].nr_replicas = k.k->type == KEY_TYPE_reflink_v
? 0 : bch2_bkey_nr_ptrs_fully_allocated(k);
s->s[i].state = k.k->type == KEY_TYPE_reservation
? SECTOR_RESERVED
: SECTOR_ALLOCATED;
}
}

bch2_trans_iter_put(&trans, iter);
bch2_trans_exit(&trans);

return s;
}

/**
* bch2_page_state_create - create bcachefs page state if not present
* @c: bcachefs filesystem of the backing sectors
* @page: page to attach the bcachefs page state to
* @gfp: additional memory allocation flags
*
* Allocate the bcachefs patge private data for the given page if no data
* currently exists. If the page state already exists, return the current
* page state.
*/
static struct bch_page_state *bch2_page_state_create(struct bch_fs *c,
struct page *page,
gfp_t gfp)
{
return bch2_page_state(page) ?: __bch2_page_state_create(page, gfp);
return bch2_page_state(page) ?: __bch2_page_state_create(c, page, gfp);
}

static inline unsigned inode_nr_replicas(struct bch_fs *c, struct bch_inode_info *inode)
Expand All @@ -332,7 +415,7 @@ static int bch2_get_page_disk_reservation(struct bch_fs *c,
struct bch_inode_info *inode,
struct page *page, bool check_enospc)
{
struct bch_page_state *s = bch2_page_state_create(page, 0);
struct bch_page_state *s = bch2_page_state_create(c, page, 0);
unsigned nr_replicas = inode_nr_replicas(c, inode);
struct disk_reservation disk_res = { 0 };
unsigned i, disk_res_sectors = 0;
Expand Down Expand Up @@ -389,7 +472,7 @@ static int bch2_page_reservation_get(struct bch_fs *c,
struct bch2_page_reservation *res,
unsigned offset, unsigned len, bool check_enospc)
{
struct bch_page_state *s = bch2_page_state_create(page, 0);
struct bch_page_state *s = bch2_page_state_create(c, page, 0);
unsigned i, disk_sectors = 0, quota_sectors = 0;
int ret;

Expand Down Expand Up @@ -470,7 +553,7 @@ static void bch2_set_page_dirty(struct bch_fs *c,
unsigned offset, unsigned len)
{
struct bch_page_state *s = bch2_page_state(page);
unsigned i, dirty_sectors = 0;
unsigned int i, unallocated_sectors = 0;

WARN_ON((u64) page_offset(page) + offset + len >
round_up((u64) i_size_read(&inode->v), block_bytes(c)));
Expand All @@ -492,16 +575,26 @@ static void bch2_set_page_dirty(struct bch_fs *c,
s->s[i].replicas_reserved += sectors;
res->disk.sectors -= sectors;

if (s->s[i].state == SECTOR_UNALLOCATED)
dirty_sectors++;

s->s[i].state = max_t(unsigned, s->s[i].state, SECTOR_DIRTY);
switch (s->s[i].state) {
case SECTOR_UNALLOCATED:
unallocated_sectors++;
s->s[i].state = SECTOR_DIRTY;
break;
case SECTOR_RESERVED:
s->s[i].state = SECTOR_ALLOCATED;
break;
case SECTOR_DIRTY:
case SECTOR_ALLOCATED:
continue;
default:
BUG();
}
}

spin_unlock(&s->lock);

if (dirty_sectors)
i_sectors_acct(c, inode, &res->quota, dirty_sectors);
if (unallocated_sectors)
i_sectors_acct(c, inode, &res->quota, unallocated_sectors);

if (!PageDirty(page))
__set_page_dirty_nobuffers(page);
Expand Down Expand Up @@ -687,7 +780,7 @@ static int readpages_iter_init(struct readpages_iter *iter,

nr_pages = __readahead_batch(ractl, iter->pages, nr_pages);
for (i = 0; i < nr_pages; i++) {
__bch2_page_state_create(iter->pages[i], __GFP_NOFAIL);
__bch2_page_state_alloc(iter->pages[i], __GFP_NOFAIL);
put_page(iter->pages[i]);
}

Expand Down Expand Up @@ -767,7 +860,7 @@ static void readpage_bio_extend(struct readpages_iter *iter,
if (!page)
break;

if (!__bch2_page_state_create(page, 0)) {
if (!__bch2_page_state_alloc(page, 0)) {
put_page(page);
break;
}
Expand Down Expand Up @@ -922,7 +1015,7 @@ static void __bchfs_readpage(struct bch_fs *c, struct bch_read_bio *rbio,
struct btree_trans trans;
struct btree_iter *iter;

bch2_page_state_create(page, __GFP_NOFAIL);
bch2_page_state_create(c, page, __GFP_NOFAIL);

bio_set_op_attrs(&rbio->bio, REQ_OP_READ, REQ_SYNC);
rbio->bio.bi_iter.bi_sector =
Expand Down Expand Up @@ -1156,7 +1249,7 @@ static int __bch2_writepage(struct page *page,
*/
zero_user_segment(page, offset, PAGE_SIZE);
do_io:
s = bch2_page_state_create(page, __GFP_NOFAIL);
s = bch2_page_state_create(c, page, __GFP_NOFAIL);

ret = bch2_get_page_disk_reservation(c, inode, page, true);
if (ret) {
Expand Down Expand Up @@ -2199,7 +2292,7 @@ static int __bch2_truncate_page(struct bch_inode_info *inode,
}
}

s = bch2_page_state_create(page, 0);
s = bch2_page_state_create(c, page, 0);
if (!s) {
ret = -ENOMEM;
goto unlock;
Expand Down

0 comments on commit 3fe6e97

Please sign in to comment.