| Message ID | 20170414120257.8932-9-rgoldwyn@suse.de (mailing list archive) |
|---|---|
| State | Not Applicable |
| Headers | show |
On Fri, Apr 14, 2017 at 07:02:57AM -0500, Goldwyn Rodrigues wrote: > From: Goldwyn Rodrigues <rgoldwyn@suse.com> > > Return EAGAIN if any of the following checks fail > + i_rwsem is not lockable > + NODATACOW or PREALLOC is not set > + Cannot nocow at the desired location > + Writing beyond end of file which is not allocated > > Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com> Acked-by: David Sterba <dsterba@suse.com> > + if ((iocb->ki_flags & IOCB_NOWAIT) && > + (iocb->ki_flags & IOCB_DIRECT)) { > + /* Don't sleep on inode rwsem */ > + if (!inode_trylock(inode)) > + return -EAGAIN; > + /* > + * We will allocate space in case nodatacow is not set, > + * so bail > + */ > + if (!(BTRFS_I(inode)->flags & (BTRFS_INODE_NODATACOW | > + BTRFS_INODE_PREALLOC)) || > + check_can_nocow(BTRFS_I(inode), pos, &count) <= 0) { > + inode_unlock(inode); > + return -EAGAIN; > + } > + } else } else { > + inode_lock(inode); } -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c index 520cb7230b2d..a870e5dd2b4d 100644 --- a/fs/btrfs/file.c +++ b/fs/btrfs/file.c @@ -1823,12 +1823,29 @@ static ssize_t btrfs_file_write_iter(struct kiocb *iocb, ssize_t num_written = 0; bool sync = (file->f_flags & O_DSYNC) || IS_SYNC(file->f_mapping->host); ssize_t err; - loff_t pos; - size_t count; + loff_t pos = iocb->ki_pos; + size_t count = iov_iter_count(from); loff_t oldsize; int clean_page = 0; - inode_lock(inode); + if ((iocb->ki_flags & IOCB_NOWAIT) && + (iocb->ki_flags & IOCB_DIRECT)) { + /* Don't sleep on inode rwsem */ + if (!inode_trylock(inode)) + return -EAGAIN; + /* + * We will allocate space in case nodatacow is not set, + * so bail + */ + if (!(BTRFS_I(inode)->flags & (BTRFS_INODE_NODATACOW | + BTRFS_INODE_PREALLOC)) || + check_can_nocow(BTRFS_I(inode), pos, &count) <= 0) { + inode_unlock(inode); + return -EAGAIN; + } + } else + inode_lock(inode); + err = generic_write_checks(iocb, from); if (err <= 0) { inode_unlock(inode); @@ -1862,8 +1879,6 @@ static ssize_t btrfs_file_write_iter(struct kiocb *iocb, */ update_time_for_write(inode); - pos = iocb->ki_pos; - count = iov_iter_count(from); start_pos = round_down(pos, fs_info->sectorsize); oldsize = i_size_read(inode); if (start_pos > oldsize) { diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index a18510be76c1..d91b21a76d6d 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -8627,6 +8627,9 @@ static ssize_t btrfs_direct_IO(struct kiocb *iocb, struct iov_iter *iter) dio_data.overwrite = 1; inode_unlock(inode); relock = true; + } else if (iocb->ki_flags & IOCB_NOWAIT) { + ret = -EAGAIN; + goto out; } ret = btrfs_delalloc_reserve_space(inode, offset, count); if (ret)