diff options
| -rw-r--r-- | fs/btrfs/inode.c | 38 |
1 files changed, 35 insertions, 3 deletions
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index 5ab120d544b..6866c36c26f 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -5722,6 +5722,32 @@ free_ordered: bio_endio(bio, ret); } +static ssize_t check_direct_IO(struct btrfs_root *root, int rw, struct kiocb *iocb, + const struct iovec *iov, loff_t offset, + unsigned long nr_segs) +{ + int seg; + size_t size; + unsigned long addr; + unsigned blocksize_mask = root->sectorsize - 1; + ssize_t retval = -EINVAL; + loff_t end = offset; + + if (offset & blocksize_mask) + goto out; + + /* Check the memory alignment. Blocks cannot straddle pages */ + for (seg = 0; seg < nr_segs; seg++) { + addr = (unsigned long)iov[seg].iov_base; + size = iov[seg].iov_len; + end += size; + if ((addr & blocksize_mask) || (size & blocksize_mask)) + goto out; + } + retval = 0; +out: + return retval; +} static ssize_t btrfs_direct_IO(int rw, struct kiocb *iocb, const struct iovec *iov, loff_t offset, unsigned long nr_segs) @@ -5736,6 +5762,11 @@ static ssize_t btrfs_direct_IO(int rw, struct kiocb *iocb, int write_bits = 0; size_t count = iov_length(iov, nr_segs); + if (check_direct_IO(BTRFS_I(inode)->root, rw, iocb, iov, + offset, nr_segs)) { + return 0; + } + lockstart = offset; lockend = offset + count - 1; @@ -5784,9 +5815,10 @@ static ssize_t btrfs_direct_IO(int rw, struct kiocb *iocb, free_extent_state(cached_state); cached_state = NULL; - ret = __blockdev_direct_IO(rw, iocb, inode, NULL, iov, offset, nr_segs, - btrfs_get_blocks_direct, NULL, - btrfs_submit_direct, 0); + ret = __blockdev_direct_IO(rw, iocb, inode, + BTRFS_I(inode)->root->fs_info->fs_devices->latest_bdev, + iov, offset, nr_segs, btrfs_get_blocks_direct, NULL, + btrfs_submit_direct, 0); if (ret < 0 && ret != -EIOCBQUEUED) { clear_extent_bit(&BTRFS_I(inode)->io_tree, offset, |