diff options
Diffstat (limited to 'fs/ceph')
-rw-r--r-- | fs/ceph/file.c | 65 |
1 files changed, 64 insertions, 1 deletions
diff --git a/fs/ceph/file.c b/fs/ceph/file.c index f4d8bf7dec88..4285f6cb5d3b 100644 --- a/fs/ceph/file.c +++ b/fs/ceph/file.c @@ -1746,6 +1746,69 @@ again: } /* + * Wrap filemap_splice_read with checks for cap bits on the inode. + * Atomically grab references, so that those bits are not released + * back to the MDS mid-read. + */ +static ssize_t ceph_splice_read(struct file *in, loff_t *ppos, + struct pipe_inode_info *pipe, + size_t len, unsigned int flags) +{ + struct ceph_file_info *fi = in->private_data; + struct inode *inode = file_inode(in); + struct ceph_inode_info *ci = ceph_inode(inode); + ssize_t ret; + int want = 0, got = 0; + CEPH_DEFINE_RW_CONTEXT(rw_ctx, 0); + + dout("splice_read %p %llx.%llx %llu~%zu trying to get caps on %p\n", + inode, ceph_vinop(inode), *ppos, len, inode); + + if (ceph_inode_is_shutdown(inode)) + return -ESTALE; + + if (ceph_has_inline_data(ci) || + (fi->flags & CEPH_F_SYNC)) + return copy_splice_read(in, ppos, pipe, len, flags); + + ceph_start_io_read(inode); + + want = CEPH_CAP_FILE_CACHE; + if (fi->fmode & CEPH_FILE_MODE_LAZY) + want |= CEPH_CAP_FILE_LAZYIO; + + ret = ceph_get_caps(in, CEPH_CAP_FILE_RD, want, -1, &got); + if (ret < 0) + goto out_end; + + if ((got & (CEPH_CAP_FILE_CACHE | CEPH_CAP_FILE_LAZYIO)) == 0) { + dout("splice_read/sync %p %llx.%llx %llu~%zu got cap refs on %s\n", + inode, ceph_vinop(inode), *ppos, len, + ceph_cap_string(got)); + + ceph_put_cap_refs(ci, got); + ceph_end_io_read(inode); + return copy_splice_read(in, ppos, pipe, len, flags); + } + + dout("splice_read %p %llx.%llx %llu~%zu got cap refs on %s\n", + inode, ceph_vinop(inode), *ppos, len, ceph_cap_string(got)); + + rw_ctx.caps = got; + ceph_add_rw_context(fi, &rw_ctx); + ret = filemap_splice_read(in, ppos, pipe, len, flags); + ceph_del_rw_context(fi, &rw_ctx); + + dout("splice_read %p %llx.%llx dropping cap refs on %s = %zd\n", + inode, ceph_vinop(inode), ceph_cap_string(got), ret); + + ceph_put_cap_refs(ci, got); +out_end: + ceph_end_io_read(inode); + return ret; +} + +/* * Take cap references to avoid releasing caps to MDS mid-write. * * If we are synchronous, and write with an old snap context, the OSD @@ -2593,7 +2656,7 @@ const struct file_operations ceph_file_fops = { .lock = ceph_lock, .setlease = simple_nosetlease, .flock = ceph_flock, - .splice_read = generic_file_splice_read, + .splice_read = ceph_splice_read, .splice_write = iter_file_splice_write, .unlocked_ioctl = ceph_ioctl, .compat_ioctl = compat_ptr_ioctl, |