diff options
Diffstat (limited to 'fs/ext4')
| -rw-r--r-- | fs/ext4/ext4.h | 3 | ||||
| -rw-r--r-- | fs/ext4/inode.c | 42 | ||||
| -rw-r--r-- | fs/ext4/ioctl.c | 14 |
3 files changed, 59 insertions, 0 deletions
diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h index 096456c8559b..b0ea70cc94db 100644 --- a/fs/ext4/ext4.h +++ b/fs/ext4/ext4.h @@ -317,7 +317,9 @@ struct ext4_new_group_data { #define EXT4_IOC_GROUP_EXTEND _IOW('f', 7, unsigned long) #define EXT4_IOC_GROUP_ADD _IOW('f', 8, struct ext4_new_group_input) #define EXT4_IOC_MIGRATE _IO('f', 9) + /* note ioctl 10 reserved for an early version of the FIEMAP ioctl */ /* note ioctl 11 reserved for filesystem-independent FIEMAP ioctl */ +#define EXT4_IOC_ALLOC_DA_BLKS _IO('f', 12) /* * ioctl commands in 32 bit emulation @@ -1094,6 +1096,7 @@ extern int ext4_can_truncate(struct inode *inode); extern void ext4_truncate(struct inode *); extern void ext4_set_inode_flags(struct inode *); extern void ext4_get_inode_flags(struct ext4_inode_info *); +extern int ext4_alloc_da_blocks(struct inode *inode); extern void ext4_set_aops(struct inode *inode); extern int ext4_writepage_trans_blocks(struct inode *); extern int ext4_meta_trans_blocks(struct inode *, int nrblocks, int idxblocks); diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c index 24d0f9d2b320..8dd3d5de5861 100644 --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -2837,6 +2837,48 @@ out: return; } +/* + * Force all delayed allocation blocks to be allocated for a given inode. + */ +int ext4_alloc_da_blocks(struct inode *inode) +{ + if (!EXT4_I(inode)->i_reserved_data_blocks && + !EXT4_I(inode)->i_reserved_meta_blocks) + return 0; + + /* + * We do something simple for now. The filemap_flush() will + * also start triggering a write of the data blocks, which is + * not strictly speaking necessary (and for users of + * laptop_mode, not even desirable). However, to do otherwise + * would require replicating code paths in: + * + * ext4_da_writepages() -> + * write_cache_pages() ---> (via passed in callback function) + * __mpage_da_writepage() --> + * mpage_add_bh_to_extent() + * mpage_da_map_blocks() + * + * The problem is that write_cache_pages(), located in + * mm/page-writeback.c, marks pages clean in preparation for + * doing I/O, which is not desirable if we're not planning on + * doing I/O at all. + * + * We could call write_cache_pages(), and then redirty all of + * the pages by calling redirty_page_for_writeback() but that + * would be ugly in the extreme. So instead we would need to + * replicate parts of the code in the above functions, + * simplifying them becuase we wouldn't actually intend to + * write out the pages, but rather only collect contiguous + * logical block extents, call the multi-block allocator, and + * then update the buffer heads with the block allocations. + * + * For now, though, we'll cheat by calling filemap_flush(), + * which will map the blocks, and start the I/O, but not + * actually wait for the I/O to complete. + */ + return filemap_flush(inode->i_mapping); +} /* * bmap() is special. It gets used by applications such as lilo and by diff --git a/fs/ext4/ioctl.c b/fs/ext4/ioctl.c index 22dd29f3ebc9..91e75f7a9e73 100644 --- a/fs/ext4/ioctl.c +++ b/fs/ext4/ioctl.c @@ -262,6 +262,20 @@ setversion_out: return err; } + case EXT4_IOC_ALLOC_DA_BLKS: + { + int err; + if (!is_owner_or_cap(inode)) + return -EACCES; + + err = mnt_want_write(filp->f_path.mnt); + if (err) + return err; + err = ext4_alloc_da_blocks(inode); + mnt_drop_write(filp->f_path.mnt); + return err; + } + default: return -ENOTTY; } |