From 2e9ee850355593e311d9a26542290fe51e152f74 Mon Sep 17 00:00:00 2001 From: "Aneesh Kumar K.V" Date: Fri, 11 Jul 2008 19:27:31 -0400 Subject: ext4: Use page_mkwrite vma_operations to get mmap write notification. We would like to get notified when we are doing a write on mmap section. This is needed with respect to preallocated area. We split the preallocated area into initialzed extent and uninitialzed extent in the call back. This let us handle ENOSPC better. Otherwise we get ENOSPC in the writepage and that would result in data loss. The changes are also needed to handle ENOSPC when writing to an mmap section of files with holes. Acked-by: Jan Kara Signed-off-by: Aneesh Kumar K.V Signed-off-by: Mingming Cao Signed-off-by: "Theodore Ts'o" --- fs/ext4/file.c | 19 ++++++++++++++++++- 1 file changed, 18 insertions(+), 1 deletion(-) (limited to 'fs/ext4/file.c') diff --git a/fs/ext4/file.c b/fs/ext4/file.c index 4159be6366a..b9510ba66a2 100644 --- a/fs/ext4/file.c +++ b/fs/ext4/file.c @@ -123,6 +123,23 @@ force_commit: return ret; } +static struct vm_operations_struct ext4_file_vm_ops = { + .fault = filemap_fault, + .page_mkwrite = ext4_page_mkwrite, +}; + +static int ext4_file_mmap(struct file *file, struct vm_area_struct *vma) +{ + struct address_space *mapping = file->f_mapping; + + if (!mapping->a_ops->readpage) + return -ENOEXEC; + file_accessed(file); + vma->vm_ops = &ext4_file_vm_ops; + vma->vm_flags |= VM_CAN_NONLINEAR; + return 0; +} + const struct file_operations ext4_file_operations = { .llseek = generic_file_llseek, .read = do_sync_read, @@ -133,7 +150,7 @@ const struct file_operations ext4_file_operations = { #ifdef CONFIG_COMPAT .compat_ioctl = ext4_compat_ioctl, #endif - .mmap = generic_file_mmap, + .mmap = ext4_file_mmap, .open = generic_file_open, .release = ext4_release_file, .fsync = ext4_sync_file, -- cgit v1.2.3-70-g09d2 From 3e3398a08d6e516675d5af853d625dc7dd90eab1 Mon Sep 17 00:00:00 2001 From: Mingming Cao Date: Fri, 11 Jul 2008 19:27:31 -0400 Subject: ext4: delayed allocation i_blocks fix for stat Right now i_blocks is not getting updated until the blocks are actually allocaed on disk. This means with delayed allocation, right after files are copied, "ls -sF" shoes the file as taking 0 blocks on disk. "du" also shows the files taking zero space, which is highly confusing to the user. Since delayed allocation already keeps track of per-inode total number of blocks that are subject to delayed allocation, this patch fix this by using that to adjust the value returned by stat(2). When real block allocation is done, the i_blocks will get updated. Since the reserved blocks for delayed allocation will be decreased, this will be keep value returned by stat(2) consistent. Signed-off-by: Mingming Cao Signed-off-by: "Theodore Ts'o" --- fs/ext4/ext4.h | 2 ++ fs/ext4/file.c | 1 + fs/ext4/inode.c | 26 ++++++++++++++++++++++++++ 3 files changed, 29 insertions(+) (limited to 'fs/ext4/file.c') diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h index 0962f4e2657..303e41cf7b1 100644 --- a/fs/ext4/ext4.h +++ b/fs/ext4/ext4.h @@ -1059,6 +1059,8 @@ int ext4_get_blocks_handle(handle_t *handle, struct inode *inode, extern struct inode *ext4_iget(struct super_block *, unsigned long); extern int ext4_write_inode (struct inode *, int); extern int ext4_setattr (struct dentry *, struct iattr *); +extern int ext4_getattr(struct vfsmount *mnt, struct dentry *dentry, + struct kstat *stat); extern void ext4_delete_inode (struct inode *); extern int ext4_sync_inode (handle_t *, struct inode *); extern void ext4_discard_reservation (struct inode *); diff --git a/fs/ext4/file.c b/fs/ext4/file.c index b9510ba66a2..430eb7978db 100644 --- a/fs/ext4/file.c +++ b/fs/ext4/file.c @@ -161,6 +161,7 @@ const struct file_operations ext4_file_operations = { const struct inode_operations ext4_file_inode_operations = { .truncate = ext4_truncate, .setattr = ext4_setattr, + .getattr = ext4_getattr, #ifdef CONFIG_EXT4DEV_FS_XATTR .setxattr = generic_setxattr, .getxattr = generic_getxattr, diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c index 0fbe678d40b..8ca2763df09 100644 --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -4231,6 +4231,32 @@ err_out: return error; } +int ext4_getattr(struct vfsmount *mnt, struct dentry *dentry, + struct kstat *stat) +{ + struct inode *inode; + unsigned long delalloc_blocks; + + inode = dentry->d_inode; + generic_fillattr(inode, stat); + + /* + * We can't update i_blocks if the block allocation is delayed + * otherwise in the case of system crash before the real block + * allocation is done, we will have i_blocks inconsistent with + * on-disk file blocks. + * We always keep i_blocks updated together with real + * allocation. But to not confuse with user, stat + * will return the blocks that include the delayed allocation + * blocks for this file. + */ + spin_lock(&EXT4_I(inode)->i_block_reservation_lock); + delalloc_blocks = EXT4_I(inode)->i_reserved_data_blocks; + spin_unlock(&EXT4_I(inode)->i_block_reservation_lock); + + stat->blocks += (delalloc_blocks << inode->i_sb->s_blocksize_bits)>>9; + return 0; +} /* * How many blocks doth make a writepage()? -- cgit v1.2.3-70-g09d2