ceph: avoid block operation when !TASK_RUNNING (ceph_get_caps)

we should not do block operation in wait_event_interruptible()'s condition
check function, but reading inline data can block. so move the read inline
data code to ceph_get_caps()

Signed-off-by: Yan, Zheng <zyan@redhat.com>
This commit is contained in:
Yan, Zheng 2015-01-09 15:56:18 +08:00 committed by Ilya Dryomov
parent d3383a8e37
commit c4d4a582c5

View File

@ -2072,17 +2072,16 @@ static void __take_cap_refs(struct ceph_inode_info *ci, int got)
* requested from the MDS.
*/
static int try_get_cap_refs(struct ceph_inode_info *ci, int need, int want,
loff_t endoff, int *got, struct page **pinned_page,
int *check_max, int *err)
loff_t endoff, int *got, int *check_max, int *err)
{
struct inode *inode = &ci->vfs_inode;
int ret = 0;
int have, implemented, _got = 0;
int have, implemented;
int file_wanted;
dout("get_cap_refs %p need %s want %s\n", inode,
ceph_cap_string(need), ceph_cap_string(want));
again:
spin_lock(&ci->i_ceph_lock);
/* make sure file is actually open */
@ -2137,8 +2136,8 @@ again:
inode, ceph_cap_string(have), ceph_cap_string(not),
ceph_cap_string(revoking));
if ((revoking & not) == 0) {
_got = need | (have & want);
__take_cap_refs(ci, _got);
*got = need | (have & want);
__take_cap_refs(ci, *got);
ret = 1;
}
} else {
@ -2163,39 +2162,8 @@ again:
out_unlock:
spin_unlock(&ci->i_ceph_lock);
if (ci->i_inline_version != CEPH_INLINE_NONE &&
(_got & (CEPH_CAP_FILE_CACHE|CEPH_CAP_FILE_LAZYIO)) &&
i_size_read(inode) > 0) {
int ret1;
struct page *page = find_get_page(inode->i_mapping, 0);
if (page) {
if (PageUptodate(page)) {
*pinned_page = page;
goto out;
}
page_cache_release(page);
}
/*
* drop cap refs first because getattr while holding
* caps refs can cause deadlock.
*/
ceph_put_cap_refs(ci, _got);
_got = 0;
/* getattr request will bring inline data into page cache */
ret1 = __ceph_do_getattr(inode, NULL,
CEPH_STAT_CAP_INLINE_DATA, true);
if (ret1 >= 0) {
ret = 0;
goto again;
}
*err = ret1;
ret = 1;
}
out:
dout("get_cap_refs %p ret %d got %s\n", inode,
ret, ceph_cap_string(_got));
*got = _got;
ret, ceph_cap_string(*got));
return ret;
}
@ -2235,22 +2203,52 @@ static void check_max_size(struct inode *inode, loff_t endoff)
int ceph_get_caps(struct ceph_inode_info *ci, int need, int want,
loff_t endoff, int *got, struct page **pinned_page)
{
int check_max, ret, err;
int _got, check_max, ret, err = 0;
retry:
if (endoff > 0)
check_max_size(&ci->vfs_inode, endoff);
_got = 0;
check_max = 0;
err = 0;
ret = wait_event_interruptible(ci->i_cap_wq,
try_get_cap_refs(ci, need, want, endoff,
got, pinned_page,
&check_max, &err));
try_get_cap_refs(ci, need, want, endoff,
&_got, &check_max, &err));
if (err)
ret = err;
if (ret < 0)
return ret;
if (check_max)
goto retry;
return ret;
if (ci->i_inline_version != CEPH_INLINE_NONE &&
(_got & (CEPH_CAP_FILE_CACHE|CEPH_CAP_FILE_LAZYIO)) &&
i_size_read(&ci->vfs_inode) > 0) {
struct page *page = find_get_page(ci->vfs_inode.i_mapping, 0);
if (page) {
if (PageUptodate(page)) {
*pinned_page = page;
goto out;
}
page_cache_release(page);
}
/*
* drop cap refs first because getattr while holding
* caps refs can cause deadlock.
*/
ceph_put_cap_refs(ci, _got);
_got = 0;
/* getattr request will bring inline data into page cache */
ret = __ceph_do_getattr(&ci->vfs_inode, NULL,
CEPH_STAT_CAP_INLINE_DATA, true);
if (ret < 0)
return ret;
goto retry;
}
out:
*got = _got;
return 0;
}
/*