Btrfs: use helper to simplify lock/unlock pages

Since we have a helper to set page bits, let lock_delalloc_pages and
__unlock_for_delalloc use it.

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This commit is contained in:
Liu Bo 2017-02-10 16:42:14 +01:00 committed by David Sterba
parent da2c7009f6
commit 76c0021db8

View file

@ -1563,29 +1563,15 @@ static noinline void __unlock_for_delalloc(struct inode *inode,
struct page *locked_page,
u64 start, u64 end)
{
int ret;
struct page *pages[16];
unsigned long index = start >> PAGE_SHIFT;
unsigned long end_index = end >> PAGE_SHIFT;
unsigned long nr_pages = end_index - index + 1;
int i;
ASSERT(locked_page);
if (index == locked_page->index && end_index == index)
return;
while (nr_pages > 0) {
ret = find_get_pages_contig(inode->i_mapping, index,
min_t(unsigned long, nr_pages,
ARRAY_SIZE(pages)), pages);
for (i = 0; i < ret; i++) {
if (pages[i] != locked_page)
unlock_page(pages[i]);
put_page(pages[i]);
}
nr_pages -= ret;
index += ret;
cond_resched();
}
__process_pages_contig(inode->i_mapping, locked_page, index, end_index,
PAGE_UNLOCK, NULL);
}
static noinline int lock_delalloc_pages(struct inode *inode,
@ -1594,59 +1580,19 @@ static noinline int lock_delalloc_pages(struct inode *inode,
u64 delalloc_end)
{
unsigned long index = delalloc_start >> PAGE_SHIFT;
unsigned long start_index = index;
unsigned long index_ret = index;
unsigned long end_index = delalloc_end >> PAGE_SHIFT;
unsigned long pages_locked = 0;
struct page *pages[16];
unsigned long nrpages;
int ret;
int i;
/* the caller is responsible for locking the start index */
ASSERT(locked_page);
if (index == locked_page->index && index == end_index)
return 0;
/* skip the page at the start index */
nrpages = end_index - index + 1;
while (nrpages > 0) {
ret = find_get_pages_contig(inode->i_mapping, index,
min_t(unsigned long,
nrpages, ARRAY_SIZE(pages)), pages);
if (ret == 0) {
ret = -EAGAIN;
goto done;
}
/* now we have an array of pages, lock them all */
for (i = 0; i < ret; i++) {
/*
* the caller is taking responsibility for
* locked_page
*/
if (pages[i] != locked_page) {
lock_page(pages[i]);
if (!PageDirty(pages[i]) ||
pages[i]->mapping != inode->i_mapping) {
ret = -EAGAIN;
unlock_page(pages[i]);
put_page(pages[i]);
goto done;
}
}
put_page(pages[i]);
pages_locked++;
}
nrpages -= ret;
index += ret;
cond_resched();
}
ret = 0;
done:
if (ret && pages_locked) {
__unlock_for_delalloc(inode, locked_page,
delalloc_start,
((u64)(start_index + pages_locked - 1)) <<
PAGE_SHIFT);
}
ret = __process_pages_contig(inode->i_mapping, locked_page, index,
end_index, PAGE_LOCK, &index_ret);
if (ret == -EAGAIN)
__unlock_for_delalloc(inode, locked_page, delalloc_start,
(u64)index_ret << PAGE_SHIFT);
return ret;
}