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| author | Yan, Zheng <zyan@redhat.com> | 2018-03-16 06:22:29 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-04-08 15:26:27 +0300 |
| commit | f00a344718dddd1a60e3926f4900d31d1b3ff182 (patch) | |
| tree | e3bfee33454c37d916fccb9d47673a417f0aa886 /fs/ceph | |
| parent | ca04476df8fd39c71818352db43090bd17dd1d58 (diff) | |
| download | linux-f00a344718dddd1a60e3926f4900d31d1b3ff182.tar.xz | |
ceph: only dirty ITER_IOVEC pages for direct read
commit 85784f9395987a422fa04263e7c0fb13da11eb5c upstream.
If a page is already locked, attempting to dirty it leads to a deadlock
in lock_page(). This is what currently happens to ITER_BVEC pages when
a dio-enabled loop device is backed by ceph:
$ losetup --direct-io /dev/loop0 /mnt/cephfs/img
$ xfs_io -c 'pread 0 4k' /dev/loop0
Follow other file systems and only dirty ITER_IOVEC pages.
Cc: stable@kernel.org
Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Reviewed-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'fs/ceph')
| -rw-r--r-- | fs/ceph/file.c | 9 |
1 files changed, 6 insertions, 3 deletions
diff --git a/fs/ceph/file.c b/fs/ceph/file.c index 5c17125f45c7..0024d3e61bcd 100644 --- a/fs/ceph/file.c +++ b/fs/ceph/file.c @@ -635,7 +635,8 @@ static ssize_t ceph_sync_read(struct kiocb *iocb, struct iov_iter *to, struct ceph_aio_request { struct kiocb *iocb; size_t total_len; - int write; + bool write; + bool should_dirty; int error; struct list_head osd_reqs; unsigned num_reqs; @@ -745,7 +746,7 @@ static void ceph_aio_complete_req(struct ceph_osd_request *req) } } - ceph_put_page_vector(osd_data->pages, num_pages, !aio_req->write); + ceph_put_page_vector(osd_data->pages, num_pages, aio_req->should_dirty); ceph_osdc_put_request(req); if (rc < 0) @@ -842,6 +843,7 @@ ceph_direct_read_write(struct kiocb *iocb, struct iov_iter *iter, size_t count = iov_iter_count(iter); loff_t pos = iocb->ki_pos; bool write = iov_iter_rw(iter) == WRITE; + bool should_dirty = !write && iter_is_iovec(iter); if (write && ceph_snap(file_inode(file)) != CEPH_NOSNAP) return -EROFS; @@ -909,6 +911,7 @@ ceph_direct_read_write(struct kiocb *iocb, struct iov_iter *iter, if (aio_req) { aio_req->iocb = iocb; aio_req->write = write; + aio_req->should_dirty = should_dirty; INIT_LIST_HEAD(&aio_req->osd_reqs); if (write) { aio_req->mtime = mtime; @@ -966,7 +969,7 @@ ceph_direct_read_write(struct kiocb *iocb, struct iov_iter *iter, len = ret; } - ceph_put_page_vector(pages, num_pages, !write); + ceph_put_page_vector(pages, num_pages, should_dirty); ceph_osdc_put_request(req); if (ret < 0) |