From 4a001071d3549f596c7c3736c5dda8a3a4aba9ed Mon Sep 17 00:00:00 2001 From: Miao Xie Date: Mon, 7 Jun 2010 03:38:51 +0000 Subject: Btrfs: fix loop device on top of btrfs We cannot use the loop device which has been connected to a file in the btrf The reproduce steps is following: # dd if=/dev/zero of=vdev0 bs=1M count=1024 # losetup /dev/loop0 vdev0 # mkfs.btrfs /dev/loop0 ... failed to zero device start -5 The reason is that the btrfs don't implement either ->write_begin or ->write the VFS API, so we fix it by setting ->write to do_sync_write(). Signed-off-by: Miao Xie Signed-off-by: Chris Mason --- fs/btrfs/file.c | 1 + 1 file changed, 1 insertion(+) (limited to 'fs/btrfs/file.c') diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c index 79437c5eeb1e..abcb91867b56 100644 --- a/fs/btrfs/file.c +++ b/fs/btrfs/file.c @@ -1197,6 +1197,7 @@ static int btrfs_file_mmap(struct file *filp, struct vm_area_struct *vma) const struct file_operations btrfs_file_operations = { .llseek = generic_file_llseek, .read = do_sync_read, + .write = do_sync_write, .aio_read = generic_file_aio_read, .splice_read = generic_file_splice_read, .aio_write = btrfs_file_aio_write, -- cgit v1.2.2 From 058a457ef0ce28d595af53d6103db73332383cbc Mon Sep 17 00:00:00 2001 From: Miao Xie Date: Thu, 20 May 2010 07:21:50 +0000 Subject: Btrfs: fix remap_file_pages error when we use remap_file_pages() to remap a file, remap_file_pages always return error. It is because btrfs didn't set VM_CAN_NONLINEAR for vma. Signed-off-by: Miao Xie Signed-off-by: Chris Mason --- fs/btrfs/file.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) (limited to 'fs/btrfs/file.c') diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c index abcb91867b56..ce0cd29efa9e 100644 --- a/fs/btrfs/file.c +++ b/fs/btrfs/file.c @@ -1189,8 +1189,15 @@ static const struct vm_operations_struct btrfs_file_vm_ops = { static int btrfs_file_mmap(struct file *filp, struct vm_area_struct *vma) { - vma->vm_ops = &btrfs_file_vm_ops; + struct address_space *mapping = filp->f_mapping; + + if (!mapping->a_ops->readpage) + return -ENOEXEC; + file_accessed(filp); + vma->vm_ops = &btrfs_file_vm_ops; + vma->vm_flags |= VM_CAN_NONLINEAR; + return 0; } -- cgit v1.2.2 From 6f902af400b2499c80865c62a06fbbd15cf804fd Mon Sep 17 00:00:00 2001 From: Dan Carpenter Date: Sat, 29 May 2010 09:49:07 +0000 Subject: Btrfs: The file argument for fsync() is never null The "file" argument for fsync is never null so we can remove this check. What drew my attention here is that 7ea8085910e: "drop unused dentry argument to ->fsync" introduced an unconditional dereference at the start of the function and that generated a smatch warning. Signed-off-by: Dan Carpenter Signed-off-by: Chris Mason --- fs/btrfs/file.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'fs/btrfs/file.c') diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c index ce0cd29efa9e..7f29464c0ebf 100644 --- a/fs/btrfs/file.c +++ b/fs/btrfs/file.c @@ -1139,7 +1139,7 @@ int btrfs_sync_file(struct file *file, struct dentry *dentry, int datasync) /* * ok we haven't committed the transaction yet, lets do a commit */ - if (file && file->private_data) + if (file->private_data) btrfs_ioctl_trans_end(file); trans = btrfs_start_transaction(root, 0); -- cgit v1.2.2