From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Subject: [PATCH 17/25] vfs: make remapping to source file eof more explicit From: "Darrick J. Wong" To: david@fromorbit.com, darrick.wong@oracle.com Cc: sandeen@redhat.com, linux-nfs@vger.kernel.org, linux-cifs@vger.kernel.org, linux-unionfs@vger.kernel.org, linux-xfs@vger.kernel.org, linux-mm@kvack.org, linux-btrfs@vger.kernel.org, linux-fsdevel@vger.kernel.org, ocfs2-devel@oss.oracle.com Date: Tue, 09 Oct 2018 17:13:57 -0700 Message-ID: <153913043746.32295.17463515265798256890.stgit@magnolia> In-Reply-To: <153913023835.32295.13962696655740190941.stgit@magnolia> References: <153913023835.32295.13962696655740190941.stgit@magnolia> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: From: Darrick J. Wong Create a RFR_TO_SRC_EOF flag to explicitly declare that the caller wants the remap implementation to remap to the end of the source file, once the files are locked. Signed-off-by: Darrick J. Wong --- fs/ioctl.c | 3 ++- fs/nfsd/vfs.c | 3 ++- fs/read_write.c | 13 +++++++------ include/linux/fs.h | 2 ++ 4 files changed, 13 insertions(+), 8 deletions(-) diff --git a/fs/ioctl.c b/fs/ioctl.c index 505275ec5596..7fec997abd2f 100644 --- a/fs/ioctl.c +++ b/fs/ioctl.c @@ -224,6 +224,7 @@ static long ioctl_file_clone(struct file *dst_file, unsigned long srcfd, { struct fd src_file = fdget(srcfd); loff_t cloned; + unsigned int flags = olen == 0 ? RFR_TO_SRC_EOF : 0; int ret; if (!src_file.file) @@ -232,7 +233,7 @@ static long ioctl_file_clone(struct file *dst_file, unsigned long srcfd, if (src_file.file->f_path.mnt != dst_file->f_path.mnt) goto fdput; cloned = vfs_clone_file_range(src_file.file, off, dst_file, destoff, - olen, 0); + olen, flags); if (cloned < 0) ret = cloned; else if (olen && cloned != olen) diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c index 726fc5b2b27a..d1f2ae08adf6 100644 --- a/fs/nfsd/vfs.c +++ b/fs/nfsd/vfs.c @@ -542,8 +542,9 @@ __be32 nfsd4_clone_file_range(struct file *src, u64 src_pos, struct file *dst, u64 dst_pos, u64 count) { loff_t cloned; + unsigned int flags = count == 0 ? RFR_TO_SRC_EOF : 0; - cloned = vfs_clone_file_range(src, src_pos, dst, dst_pos, count, 0); + cloned = vfs_clone_file_range(src, src_pos, dst, dst_pos, count, flags); if (count && cloned != count) cloned = -EINVAL; return nfserrno(cloned < 0 ? cloned : 0); diff --git a/fs/read_write.c b/fs/read_write.c index 479eb810c8e6..a628fd9a47cf 100644 --- a/fs/read_write.c +++ b/fs/read_write.c @@ -1748,11 +1748,12 @@ int generic_remap_file_range_prep(struct file *file_in, loff_t pos_in, isize = i_size_read(inode_in); - /* Zero length dedupe exits immediately; reflink goes to EOF. */ - if (*len == 0) { - if (is_dedupe || pos_in == isize) - return 0; - if (pos_in > isize) + /* + * If the caller asked to go all the way to the end of the source file, + * set *len now that we have the file locked. + */ + if (remap_flags & RFR_TO_SRC_EOF) { + if (pos_in >= isize) return -EINVAL; *len = isize - pos_in; } @@ -1828,7 +1829,7 @@ loff_t do_clone_file_range(struct file *file_in, loff_t pos_in, struct inode *inode_out = file_inode(file_out); loff_t ret; - WARN_ON_ONCE(remap_flags); + WARN_ON_ONCE(remap_flags & ~(RFR_TO_SRC_EOF)); if (S_ISDIR(inode_in->i_mode) || S_ISDIR(inode_out->i_mode)) return -EISDIR; diff --git a/include/linux/fs.h b/include/linux/fs.h index 5c1bf1c35bc6..9f90dcd4df3b 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -1725,8 +1725,10 @@ struct block_device_operations; * These flags control the behavior of the remap_file_range function pointer. * * RFR_IDENTICAL_DATA: only remap if contents identical (i.e. deduplicate) + * RFR_TO_SRC_EOF: remap to the end of the source file */ #define RFR_IDENTICAL_DATA (1 << 0) +#define RFR_TO_SRC_EOF (1 << 1) struct iov_iter;