Commit 46c7f254 authored by Tao Ma's avatar Tao Ma Committed by Theodore Ts'o
Browse files

ext4: add read support for inline data



Let readpage and readpages handle the case when we want to read an
inlined file.
Signed-off-by: default avatarTao Ma <boyu.mt@taobao.com>
Signed-off-by: default avatar"Theodore Ts'o" <tytso@mit.edu>
parent 67cf5b09
......@@ -454,6 +454,67 @@ static int ext4_destroy_inline_data_nolock(handle_t *handle,
return error;
}
static int ext4_read_inline_page(struct inode *inode, struct page *page)
{
void *kaddr;
int ret = 0;
size_t len;
struct ext4_iloc iloc;
BUG_ON(!PageLocked(page));
BUG_ON(!ext4_has_inline_data(inode));
BUG_ON(page->index);
if (!EXT4_I(inode)->i_inline_off) {
ext4_warning(inode->i_sb, "inode %lu doesn't have inline data.",
inode->i_ino);
goto out;
}
ret = ext4_get_inode_loc(inode, &iloc);
if (ret)
goto out;
len = min_t(size_t, ext4_get_inline_size(inode), i_size_read(inode));
kaddr = kmap_atomic(page);
ret = ext4_read_inline_data(inode, kaddr, len, &iloc);
flush_dcache_page(page);
kunmap_atomic(kaddr);
zero_user_segment(page, len, PAGE_CACHE_SIZE);
SetPageUptodate(page);
brelse(iloc.bh);
out:
return ret;
}
int ext4_readpage_inline(struct inode *inode, struct page *page)
{
int ret = 0;
down_read(&EXT4_I(inode)->xattr_sem);
if (!ext4_has_inline_data(inode)) {
up_read(&EXT4_I(inode)->xattr_sem);
return -EAGAIN;
}
/*
* Current inline data can only exist in the 1st page,
* So for all the other pages, just set them uptodate.
*/
if (!page->index)
ret = ext4_read_inline_page(inode, page);
else if (!PageUptodate(page)) {
zero_user_segment(page, 0, PAGE_CACHE_SIZE);
SetPageUptodate(page);
}
up_read(&EXT4_I(inode)->xattr_sem);
unlock_page(page);
return ret >= 0 ? 0 : ret;
}
int ext4_destroy_inline_data(handle_t *handle, struct inode *inode)
{
int ret;
......
......@@ -649,6 +649,9 @@ static int _ext4_get_block(struct inode *inode, sector_t iblock,
int ret = 0, started = 0;
int dio_credits;
if (ext4_has_inline_data(inode))
return -ERANGE;
map.m_lblk = iblock;
map.m_len = bh->b_size >> inode->i_blkbits;
......@@ -2687,6 +2690,12 @@ static sector_t ext4_bmap(struct address_space *mapping, sector_t block)
journal_t *journal;
int err;
/*
* We can get here for an inline file via the FIBMAP ioctl
*/
if (ext4_has_inline_data(inode))
return 0;
if (mapping_tagged(mapping, PAGECACHE_TAG_DIRTY) &&
test_opt(inode->i_sb, DELALLOC)) {
/*
......@@ -2732,14 +2741,30 @@ static sector_t ext4_bmap(struct address_space *mapping, sector_t block)
static int ext4_readpage(struct file *file, struct page *page)
{
int ret = -EAGAIN;
struct inode *inode = page->mapping->host;
trace_ext4_readpage(page);
return mpage_readpage(page, ext4_get_block);
if (ext4_has_inline_data(inode))
ret = ext4_readpage_inline(inode, page);
if (ret == -EAGAIN)
return mpage_readpage(page, ext4_get_block);
return ret;
}
static int
ext4_readpages(struct file *file, struct address_space *mapping,
struct list_head *pages, unsigned nr_pages)
{
struct inode *inode = mapping->host;
/* If the file has inline data, no need to do readpages. */
if (ext4_has_inline_data(inode))
return 0;
return mpage_readpages(mapping, pages, nr_pages, ext4_get_block);
}
......@@ -3078,6 +3103,10 @@ static ssize_t ext4_direct_IO(int rw, struct kiocb *iocb,
if (ext4_should_journal_data(inode))
return 0;
/* Let buffer I/O handle the inline data case. */
if (ext4_has_inline_data(inode))
return 0;
trace_ext4_direct_IO_enter(inode, offset, iov_length(iov, nr_segs), rw);
if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))
ret = ext4_ext_direct_IO(rw, iocb, iov, offset, nr_segs);
......
......@@ -139,6 +139,8 @@ extern int ext4_prepare_inline_data(handle_t *handle, struct inode *inode,
extern int ext4_init_inline_data(handle_t *handle, struct inode *inode,
unsigned int len);
extern int ext4_destroy_inline_data(handle_t *handle, struct inode *inode);
extern int ext4_readpage_inline(struct inode *inode, struct page *page);
# else /* CONFIG_EXT4_FS_XATTR */
static inline int
......@@ -255,6 +257,11 @@ static inline int ext4_destroy_inline_data(handle_t *handle,
{
return 0;
}
static inline int ext4_readpage_inline(struct inode *inode, struct page *page)
{
return 0;
}
# endif /* CONFIG_EXT4_FS_XATTR */
#ifdef CONFIG_EXT4_FS_SECURITY
......
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