ceph: try getting buffer capability for readahead/fadvise
commit 2b1ac852eb
upstream.
For readahead/fadvise cases, caller of ceph_readpages does not
hold buffer capability. Pages can be added to page cache while
there is no buffer capability. This can cause data integrity
issue.
Signed-off-by: Yan, Zheng <zyan@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
parent
1bf9bc4813
commit
e99b0ea393
|
@ -315,7 +315,32 @@ static int start_read(struct inode *inode, struct list_head *page_list, int max)
|
|||
struct page **pages;
|
||||
pgoff_t next_index;
|
||||
int nr_pages = 0;
|
||||
int ret;
|
||||
int got = 0;
|
||||
int ret = 0;
|
||||
|
||||
if (!current->journal_info) {
|
||||
/* caller of readpages does not hold buffer and read caps
|
||||
* (fadvise, madvise and readahead cases) */
|
||||
int want = CEPH_CAP_FILE_CACHE;
|
||||
ret = ceph_try_get_caps(ci, CEPH_CAP_FILE_RD, want, &got);
|
||||
if (ret < 0) {
|
||||
dout("start_read %p, error getting cap\n", inode);
|
||||
} else if (!(got & want)) {
|
||||
dout("start_read %p, no cache cap\n", inode);
|
||||
ret = 0;
|
||||
}
|
||||
if (ret <= 0) {
|
||||
if (got)
|
||||
ceph_put_cap_refs(ci, got);
|
||||
while (!list_empty(page_list)) {
|
||||
page = list_entry(page_list->prev,
|
||||
struct page, lru);
|
||||
list_del(&page->lru);
|
||||
put_page(page);
|
||||
}
|
||||
return ret;
|
||||
}
|
||||
}
|
||||
|
||||
off = (u64) page_offset(page);
|
||||
|
||||
|
@ -338,15 +363,18 @@ static int start_read(struct inode *inode, struct list_head *page_list, int max)
|
|||
CEPH_OSD_FLAG_READ, NULL,
|
||||
ci->i_truncate_seq, ci->i_truncate_size,
|
||||
false);
|
||||
if (IS_ERR(req))
|
||||
return PTR_ERR(req);
|
||||
if (IS_ERR(req)) {
|
||||
ret = PTR_ERR(req);
|
||||
goto out;
|
||||
}
|
||||
|
||||
/* build page vector */
|
||||
nr_pages = calc_pages_for(0, len);
|
||||
pages = kmalloc(sizeof(*pages) * nr_pages, GFP_KERNEL);
|
||||
ret = -ENOMEM;
|
||||
if (!pages)
|
||||
goto out;
|
||||
if (!pages) {
|
||||
ret = -ENOMEM;
|
||||
goto out_put;
|
||||
}
|
||||
for (i = 0; i < nr_pages; ++i) {
|
||||
page = list_entry(page_list->prev, struct page, lru);
|
||||
BUG_ON(PageLocked(page));
|
||||
|
@ -379,6 +407,12 @@ static int start_read(struct inode *inode, struct list_head *page_list, int max)
|
|||
if (ret < 0)
|
||||
goto out_pages;
|
||||
ceph_osdc_put_request(req);
|
||||
|
||||
/* After adding locked pages to page cache, the inode holds cache cap.
|
||||
* So we can drop our cap refs. */
|
||||
if (got)
|
||||
ceph_put_cap_refs(ci, got);
|
||||
|
||||
return nr_pages;
|
||||
|
||||
out_pages:
|
||||
|
@ -387,8 +421,11 @@ out_pages:
|
|||
unlock_page(pages[i]);
|
||||
}
|
||||
ceph_put_page_vector(pages, nr_pages, false);
|
||||
out:
|
||||
out_put:
|
||||
ceph_osdc_put_request(req);
|
||||
out:
|
||||
if (got)
|
||||
ceph_put_cap_refs(ci, got);
|
||||
return ret;
|
||||
}
|
||||
|
||||
|
@ -425,7 +462,6 @@ static int ceph_readpages(struct file *file, struct address_space *mapping,
|
|||
rc = start_read(inode, page_list, max);
|
||||
if (rc < 0)
|
||||
goto out;
|
||||
BUG_ON(rc == 0);
|
||||
}
|
||||
out:
|
||||
ceph_fscache_readpages_cancel(inode, page_list);
|
||||
|
@ -1372,9 +1408,11 @@ static int ceph_filemap_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
|
|||
inode, off, (size_t)PAGE_SIZE, ceph_cap_string(got));
|
||||
|
||||
if ((got & (CEPH_CAP_FILE_CACHE | CEPH_CAP_FILE_LAZYIO)) ||
|
||||
ci->i_inline_version == CEPH_INLINE_NONE)
|
||||
ci->i_inline_version == CEPH_INLINE_NONE) {
|
||||
current->journal_info = vma->vm_file;
|
||||
ret = filemap_fault(vma, vmf);
|
||||
else
|
||||
current->journal_info = NULL;
|
||||
} else
|
||||
ret = -EAGAIN;
|
||||
|
||||
dout("filemap_fault %p %llu~%zd dropping cap refs on %s ret %d\n",
|
||||
|
|
|
@ -2479,6 +2479,27 @@ static void check_max_size(struct inode *inode, loff_t endoff)
|
|||
ceph_check_caps(ci, CHECK_CAPS_AUTHONLY, NULL);
|
||||
}
|
||||
|
||||
int ceph_try_get_caps(struct ceph_inode_info *ci, int need, int want, int *got)
|
||||
{
|
||||
int ret, err = 0;
|
||||
|
||||
BUG_ON(need & ~CEPH_CAP_FILE_RD);
|
||||
BUG_ON(want & ~(CEPH_CAP_FILE_CACHE|CEPH_CAP_FILE_LAZYIO));
|
||||
ret = ceph_pool_perm_check(ci, need);
|
||||
if (ret < 0)
|
||||
return ret;
|
||||
|
||||
ret = try_get_cap_refs(ci, need, want, 0, true, got, &err);
|
||||
if (ret) {
|
||||
if (err == -EAGAIN) {
|
||||
ret = 0;
|
||||
} else if (err < 0) {
|
||||
ret = err;
|
||||
}
|
||||
}
|
||||
return ret;
|
||||
}
|
||||
|
||||
/*
|
||||
* Wait for caps, and take cap references. If we can't get a WR cap
|
||||
* due to a small max_size, make sure we check_max_size (and possibly
|
||||
|
|
|
@ -1249,8 +1249,9 @@ again:
|
|||
dout("aio_read %p %llx.%llx %llu~%u got cap refs on %s\n",
|
||||
inode, ceph_vinop(inode), iocb->ki_pos, (unsigned)len,
|
||||
ceph_cap_string(got));
|
||||
|
||||
current->journal_info = filp;
|
||||
ret = generic_file_read_iter(iocb, to);
|
||||
current->journal_info = NULL;
|
||||
}
|
||||
dout("aio_read %p %llx.%llx dropping cap refs on %s = %d\n",
|
||||
inode, ceph_vinop(inode), ceph_cap_string(got), (int)ret);
|
||||
|
|
|
@ -905,6 +905,8 @@ extern int ceph_encode_dentry_release(void **p, struct dentry *dn,
|
|||
|
||||
extern int ceph_get_caps(struct ceph_inode_info *ci, int need, int want,
|
||||
loff_t endoff, int *got, struct page **pinned_page);
|
||||
extern int ceph_try_get_caps(struct ceph_inode_info *ci,
|
||||
int need, int want, int *got);
|
||||
|
||||
/* for counting open files by mode */
|
||||
extern void __ceph_get_fmode(struct ceph_inode_info *ci, int mode);
|
||||
|
|
Loading…
Reference in a new issue