f2fs: split find_data_page according to specific purposes

This patch splits find_data_page as follows.

1. f2fs_gc
 - use get_read_data_page() with read only

2. find_in_level
 - use find_data_page without locked page

3. truncate_partial_page
 - In the case cache_only mode, just drop cached page.
 - Ohterwise, use get_lock_data_page() and guarantee to truncate

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This commit is contained in:
Jaegeuk Kim 2015-04-30 17:00:33 -07:00
parent 2fb2c95496
commit 43f3eae1d3
5 changed files with 68 additions and 95 deletions

View File

@ -917,7 +917,7 @@ void f2fs_update_extent_cache(struct dnode_of_data *dn)
sync_inode_page(dn);
}
struct page *find_data_page(struct inode *inode, pgoff_t index, bool sync)
struct page *get_read_data_page(struct inode *inode, pgoff_t index, int rw)
{
struct address_space *mapping = inode->i_mapping;
struct dnode_of_data dn;
@ -927,84 +927,9 @@ struct page *find_data_page(struct inode *inode, pgoff_t index, bool sync)
struct f2fs_io_info fio = {
.sbi = F2FS_I_SB(inode),
.type = DATA,
.rw = sync ? READ_SYNC : READA,
.rw = rw,
};
/*
* If sync is false, it needs to check its block allocation.
* This is need and triggered by two flows:
* gc and truncate_partial_data_page.
*/
if (!sync)
goto search;
page = find_get_page(mapping, index);
if (page && PageUptodate(page))
return page;
f2fs_put_page(page, 0);
search:
if (f2fs_lookup_extent_cache(inode, index, &ei)) {
dn.data_blkaddr = ei.blk + index - ei.fofs;
goto got_it;
}
set_new_dnode(&dn, inode, NULL, NULL, 0);
err = get_dnode_of_data(&dn, index, LOOKUP_NODE);
if (err)
return ERR_PTR(err);
f2fs_put_dnode(&dn);
if (dn.data_blkaddr == NULL_ADDR)
return ERR_PTR(-ENOENT);
/* By fallocate(), there is no cached page, but with NEW_ADDR */
if (unlikely(dn.data_blkaddr == NEW_ADDR))
return ERR_PTR(-EINVAL);
got_it:
page = grab_cache_page(mapping, index);
if (!page)
return ERR_PTR(-ENOMEM);
if (PageUptodate(page)) {
unlock_page(page);
return page;
}
fio.blk_addr = dn.data_blkaddr;
fio.page = page;
err = f2fs_submit_page_bio(&fio);
if (err)
return ERR_PTR(err);
if (sync) {
wait_on_page_locked(page);
if (unlikely(!PageUptodate(page))) {
f2fs_put_page(page, 0);
return ERR_PTR(-EIO);
}
}
return page;
}
/*
* If it tries to access a hole, return an error.
* Because, the callers, functions in dir.c and GC, should be able to know
* whether this page exists or not.
*/
struct page *get_lock_data_page(struct inode *inode, pgoff_t index)
{
struct address_space *mapping = inode->i_mapping;
struct dnode_of_data dn;
struct page *page;
struct extent_info ei;
int err;
struct f2fs_io_info fio = {
.sbi = F2FS_I_SB(inode),
.type = DATA,
.rw = READ_SYNC,
};
repeat:
page = grab_cache_page(mapping, index);
if (!page)
return ERR_PTR(-ENOMEM);
@ -1026,10 +951,11 @@ struct page *get_lock_data_page(struct inode *inode, pgoff_t index)
f2fs_put_page(page, 1);
return ERR_PTR(-ENOENT);
}
got_it:
if (PageUptodate(page))
if (PageUptodate(page)) {
unlock_page(page);
return page;
}
/*
* A new dentry page is allocated but not able to be written, since its
@ -1040,6 +966,7 @@ struct page *get_lock_data_page(struct inode *inode, pgoff_t index)
if (dn.data_blkaddr == NEW_ADDR) {
zero_user_segment(page, 0, PAGE_CACHE_SIZE);
SetPageUptodate(page);
unlock_page(page);
return page;
}
@ -1048,7 +975,49 @@ struct page *get_lock_data_page(struct inode *inode, pgoff_t index)
err = f2fs_submit_page_bio(&fio);
if (err)
return ERR_PTR(err);
return page;
}
struct page *find_data_page(struct inode *inode, pgoff_t index)
{
struct address_space *mapping = inode->i_mapping;
struct page *page;
page = find_get_page(mapping, index);
if (page && PageUptodate(page))
return page;
f2fs_put_page(page, 0);
page = get_read_data_page(inode, index, READ_SYNC);
if (IS_ERR(page))
return page;
if (PageUptodate(page))
return page;
wait_on_page_locked(page);
if (unlikely(!PageUptodate(page))) {
f2fs_put_page(page, 0);
return ERR_PTR(-EIO);
}
return page;
}
/*
* If it tries to access a hole, return an error.
* Because, the callers, functions in dir.c and GC, should be able to know
* whether this page exists or not.
*/
struct page *get_lock_data_page(struct inode *inode, pgoff_t index)
{
struct address_space *mapping = inode->i_mapping;
struct page *page;
repeat:
page = get_read_data_page(inode, index, READ_SYNC);
if (IS_ERR(page))
return page;
/* wait for read completion */
lock_page(page);
if (unlikely(!PageUptodate(page))) {
f2fs_put_page(page, 1);

View File

@ -177,7 +177,7 @@ static struct f2fs_dir_entry *find_in_level(struct inode *dir,
for (; bidx < end_block; bidx++) {
/* no need to allocate new dentry pages to all the indices */
dentry_page = find_data_page(dir, bidx, true);
dentry_page = find_data_page(dir, bidx);
if (IS_ERR(dentry_page)) {
room = true;
continue;

View File

@ -1675,7 +1675,8 @@ void f2fs_destroy_extent_tree(struct inode *);
void f2fs_init_extent_cache(struct inode *, struct f2fs_extent *);
void f2fs_update_extent_cache(struct dnode_of_data *);
void f2fs_preserve_extent_tree(struct inode *);
struct page *find_data_page(struct inode *, pgoff_t, bool);
struct page *get_read_data_page(struct inode *, pgoff_t, int);
struct page *find_data_page(struct inode *, pgoff_t);
struct page *get_lock_data_page(struct inode *, pgoff_t);
struct page *get_new_data_page(struct inode *, struct page *, pgoff_t, bool);
int do_write_data_page(struct f2fs_io_info *);

View File

@ -461,28 +461,32 @@ void truncate_data_blocks(struct dnode_of_data *dn)
}
static int truncate_partial_data_page(struct inode *inode, u64 from,
bool force)
bool cache_only)
{
unsigned offset = from & (PAGE_CACHE_SIZE - 1);
pgoff_t index = from >> PAGE_CACHE_SHIFT;
struct address_space *mapping = inode->i_mapping;
struct page *page;
if (!offset && !force)
if (!offset && !cache_only)
return 0;
page = find_data_page(inode, from >> PAGE_CACHE_SHIFT, force);
if (cache_only) {
page = grab_cache_page(mapping, index);
if (page && PageUptodate(page))
goto truncate_out;
f2fs_put_page(page, 1);
return 0;
}
page = get_lock_data_page(inode, index);
if (IS_ERR(page))
return 0;
lock_page(page);
if (unlikely(!PageUptodate(page) ||
page->mapping != inode->i_mapping))
goto out;
truncate_out:
f2fs_wait_on_page_writeback(page, DATA);
zero_user(page, offset, PAGE_CACHE_SIZE - offset);
if (!force)
if (!cache_only)
set_page_dirty(page);
out:
f2fs_put_page(page, 1);
return 0;
}

View File

@ -607,9 +607,8 @@ static void gc_data_segment(struct f2fs_sb_info *sbi, struct f2fs_summary *sum,
continue;
start_bidx = start_bidx_of_node(nofs, F2FS_I(inode));
data_page = find_data_page(inode,
start_bidx + ofs_in_node, false);
data_page = get_read_data_page(inode,
start_bidx + ofs_in_node, READA);
if (IS_ERR(data_page)) {
iput(inode);
continue;