ceph: sync read inline data
we can't use getattr to fetch inline data while holding Fr cap,
because it can cause deadlock. If we need to sync read inline data,
drop cap refs first, then use getattr to fetch inline data.
Signed-off-by: Yan, Zheng <zyan@redhat.com>
diff --git a/fs/ceph/addr.c b/fs/ceph/addr.c
index 5d2b88e..13413d7 100644
--- a/fs/ceph/addr.c
+++ b/fs/ceph/addr.c
@@ -192,17 +192,30 @@
struct ceph_osd_client *osdc =
&ceph_inode_to_client(inode)->client->osdc;
int err = 0;
+ u64 off = page_offset(page);
u64 len = PAGE_CACHE_SIZE;
- err = ceph_readpage_from_fscache(inode, page);
+ if (off >= i_size_read(inode)) {
+ zero_user_segment(page, err, PAGE_CACHE_SIZE);
+ SetPageUptodate(page);
+ return 0;
+ }
+ /*
+ * Uptodate inline data should have been added into page cache
+ * while getting Fcr caps.
+ */
+ if (ci->i_inline_version != CEPH_INLINE_NONE)
+ return -EINVAL;
+
+ err = ceph_readpage_from_fscache(inode, page);
if (err == 0)
goto out;
dout("readpage inode %p file %p page %p index %lu\n",
inode, filp, page, page->index);
err = ceph_osdc_readpages(osdc, ceph_vino(inode), &ci->i_layout,
- (u64) page_offset(page), &len,
+ off, &len,
ci->i_truncate_seq, ci->i_truncate_size,
&page, 1, 0);
if (err == -ENOENT)
@@ -384,6 +397,9 @@
int rc = 0;
int max = 0;
+ if (ceph_inode(inode)->i_inline_version != CEPH_INLINE_NONE)
+ return -EINVAL;
+
rc = ceph_readpages_from_fscache(mapping->host, mapping, page_list,
&nr_pages);
@@ -1219,8 +1235,8 @@
want = CEPH_CAP_FILE_CACHE;
while (1) {
got = 0;
- ret = ceph_get_caps(ci, CEPH_CAP_FILE_RD, want, -1,
- &got, &pinned_page);
+ ret = ceph_get_caps(ci, CEPH_CAP_FILE_RD, want,
+ -1, &got, &pinned_page);
if (ret == 0)
break;
if (ret != -ERESTARTSYS) {
@@ -1231,7 +1247,11 @@
dout("filemap_fault %p %llu~%zd got cap refs on %s\n",
inode, off, (size_t)PAGE_CACHE_SIZE, ceph_cap_string(got));
- ret = filemap_fault(vma, vmf);
+ if ((got & (CEPH_CAP_FILE_CACHE | CEPH_CAP_FILE_LAZYIO)) ||
+ ci->i_inline_version == CEPH_INLINE_NONE)
+ ret = filemap_fault(vma, vmf);
+ else
+ ret = -EAGAIN;
dout("filemap_fault %p %llu~%zd dropping cap refs on %s ret %d\n",
inode, off, (size_t)PAGE_CACHE_SIZE, ceph_cap_string(got), ret);
@@ -1239,6 +1259,42 @@
page_cache_release(pinned_page);
ceph_put_cap_refs(ci, got);
+ if (ret != -EAGAIN)
+ return ret;
+
+ /* read inline data */
+ if (off >= PAGE_CACHE_SIZE) {
+ /* does not support inline data > PAGE_SIZE */
+ ret = VM_FAULT_SIGBUS;
+ } else {
+ int ret1;
+ struct address_space *mapping = inode->i_mapping;
+ struct page *page = find_or_create_page(mapping, 0,
+ mapping_gfp_mask(mapping) &
+ ~__GFP_FS);
+ if (!page) {
+ ret = VM_FAULT_OOM;
+ goto out;
+ }
+ ret1 = __ceph_do_getattr(inode, page,
+ CEPH_STAT_CAP_INLINE_DATA, true);
+ if (ret1 < 0 || off >= i_size_read(inode)) {
+ unlock_page(page);
+ page_cache_release(page);
+ ret = VM_FAULT_SIGBUS;
+ goto out;
+ }
+ if (ret1 < PAGE_CACHE_SIZE)
+ zero_user_segment(page, ret1, PAGE_CACHE_SIZE);
+ else
+ flush_dcache_page(page);
+ SetPageUptodate(page);
+ vmf->page = page;
+ ret = VM_FAULT_MAJOR | VM_FAULT_LOCKED;
+ }
+out:
+ dout("filemap_fault %p %llu~%zd read inline data ret %d\n",
+ inode, off, (size_t)PAGE_CACHE_SIZE, ret);
return ret;
}