From: Goldwyn Rodrigues Subject: [PATCH 7/8] nowait aio: xfs Date: Tue, 28 Feb 2017 17:36:09 -0600 Message-ID: <20170228233610.25456-8-rgoldwyn@suse.de> References: <20170228233610.25456-1-rgoldwyn@suse.de> Cc: hch@infradead.org, linux-fsdevel@vger.kernel.org, linux-block@vger.kernel.org, linux-btrfs@vger.kernel.org, linux-ext4@vger.kernel.org, linux-xfs@vger.kernel.org, Goldwyn Rodrigues To: jack@suse.com Return-path: In-Reply-To: <20170228233610.25456-1-rgoldwyn@suse.de> Sender: linux-fsdevel-owner@vger.kernel.org List-Id: linux-ext4.vger.kernel.org From: Goldwyn Rodrigues If IOCB_NOWAIT is set, bail if the i_rwsem is not lockable immediately. IF IOMAP_NOWAIT is set, return EAGAIN in xfs_file_iomap_begin if it needs allocation either due to file extending, writing to a hole, or COW. Signed-off-by: Goldwyn Rodrigues --- fs/xfs/xfs_file.c | 9 +++++++-- fs/xfs/xfs_iomap.c | 9 +++++++++ 2 files changed, 16 insertions(+), 2 deletions(-) diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c index bbb9eb6..7e16a83 100644 --- a/fs/xfs/xfs_file.c +++ b/fs/xfs/xfs_file.c @@ -528,12 +528,17 @@ xfs_file_dio_aio_write( ((iocb->ki_pos + count) & mp->m_blockmask)) { unaligned_io = 1; iolock = XFS_IOLOCK_EXCL; + if (iocb->ki_flags & IOCB_NOWAIT) + return -EAGAIN; } else { iolock = XFS_IOLOCK_SHARED; } - xfs_ilock(ip, iolock); - + if (!xfs_ilock_nowait(ip, iolock)) { + if (iocb->ki_flags & IOCB_NOWAIT) + return -EAGAIN; + xfs_ilock(ip, iolock); + } ret = xfs_file_aio_write_checks(iocb, from, &iolock); if (ret) goto out; diff --git a/fs/xfs/xfs_iomap.c b/fs/xfs/xfs_iomap.c index 1aa3abd..84f981a 100644 --- a/fs/xfs/xfs_iomap.c +++ b/fs/xfs/xfs_iomap.c @@ -1020,6 +1020,11 @@ xfs_file_iomap_begin( if ((flags & IOMAP_REPORT) || (xfs_is_reflink_inode(ip) && (flags & IOMAP_WRITE) && (flags & IOMAP_DIRECT))) { + /* Allocations due to reflinks */ + if ((flags & IOMAP_NOWAIT) && !(flags & IOMAP_REPORT)) { + error = -EAGAIN; + goto out_unlock; + } /* Trim the mapping to the nearest shared extent boundary. */ error = xfs_reflink_trim_around_shared(ip, &imap, &shared, &trimmed); @@ -1049,6 +1054,10 @@ xfs_file_iomap_begin( } if ((flags & IOMAP_WRITE) && imap_needs_alloc(inode, &imap, nimaps)) { + if (flags & IOMAP_NOWAIT) { + error = -EAGAIN; + goto out_unlock; + } /* * We cap the maximum length we map here to MAX_WRITEBACK_PAGES * pages to keep the chunks of work done where somewhat symmetric -- 2.10.2