diff options
-rw-r--r-- | fs/ext4/ext4.h | 2 | ||||
-rw-r--r-- | fs/ext4/inode.c | 14 |
2 files changed, 16 insertions, 0 deletions
diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h index a743b1e3b89e..797bc572d6fb 100644 --- a/fs/ext4/ext4.h +++ b/fs/ext4/ext4.h @@ -673,6 +673,8 @@ enum { /* Caller will submit data before dropping transaction handle. This * allows jbd2 to avoid submitting data before commit. */ #define EXT4_GET_BLOCKS_IO_SUBMIT 0x0400 + /* Caller is in the atomic contex, find extent if it has been cached */ +#define EXT4_GET_BLOCKS_CACHED_NOWAIT 0x0800 /* * The bit position of these flags must not overlap with any of the diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c index 15165c87c915..f7b4787d6679 100644 --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -545,12 +545,21 @@ int ext4_map_blocks(handle_t *handle, struct inode *inode, } else { BUG(); } + + if (flags & EXT4_GET_BLOCKS_CACHED_NOWAIT) + return retval; #ifdef ES_AGGRESSIVE_TEST ext4_map_blocks_es_recheck(handle, inode, map, &orig_map, flags); #endif goto found; } + /* + * In the query cache no-wait mode, nothing we can do more if we + * cannot find extent in the cache. + */ + if (flags & EXT4_GET_BLOCKS_CACHED_NOWAIT) + return 0; /* * Try to see if we can get the block without requesting a new @@ -837,10 +846,12 @@ struct buffer_head *ext4_getblk(handle_t *handle, struct inode *inode, struct ext4_map_blocks map; struct buffer_head *bh; int create = map_flags & EXT4_GET_BLOCKS_CREATE; + bool nowait = map_flags & EXT4_GET_BLOCKS_CACHED_NOWAIT; int err; ASSERT((EXT4_SB(inode->i_sb)->s_mount_state & EXT4_FC_REPLAY) || handle != NULL || create == 0); + ASSERT(create == 0 || !nowait); map.m_lblk = block; map.m_len = 1; @@ -851,6 +862,9 @@ struct buffer_head *ext4_getblk(handle_t *handle, struct inode *inode, if (err < 0) return ERR_PTR(err); + if (nowait) + return sb_find_get_block(inode->i_sb, map.m_pblk); + bh = sb_getblk(inode->i_sb, map.m_pblk); if (unlikely(!bh)) return ERR_PTR(-ENOMEM); |