don't put symlink bodies in pagecache into highmem

kmap() in page_follow_link_light() needed to go - allowing to hold
an arbitrary number of kmaps for long is a great way to deadlocking
the system.

new helper (inode_nohighmem(inode)) needs to be used for pagecache
symlinks inodes; done for all in-tree cases.  page_follow_link_light()
instrumented to yell about anything missed.

Signed-off-by: Al Viro <[email protected]>
This commit is contained in:
Al Viro 2015-11-17 01:07:57 -05:00
commit 21fc61c73c
57 changed files with 81 additions and 46 deletions

View file

@ -41,6 +41,7 @@
#include <linux/fs.h>
#include <linux/vfs.h>
#include <linux/xattr.h>
#include <linux/pagemap.h>
#include "squashfs_fs.h"
#include "squashfs_fs_sb.h"
@ -291,6 +292,7 @@ int squashfs_read_inode(struct inode *inode, long long ino)
set_nlink(inode, le32_to_cpu(sqsh_ino->nlink));
inode->i_size = le32_to_cpu(sqsh_ino->symlink_size);
inode->i_op = &squashfs_symlink_inode_ops;
inode_nohighmem(inode);
inode->i_data.a_ops = &squashfs_symlink_aops;
inode->i_mode |= S_IFLNK;
squashfs_i(inode)->start = block;