Merge tag 'v5.6-rc3' into sched/core, to pick up fixes and dependent patches

Signed-off-by: Ingo Molnar <mingo@kernel.org>

1 files changed, 6 insertions, 51 deletions

diff --git a/fs/crypto/crypto.c b/fs/crypto/crypto.c
index 3719efa546c6..1ecaac7ee3cb 100644
--- a/fs/crypto/crypto.c
+++ b/fs/crypto/crypto.c
@@ -25,8 +25,6 @@
 #include <linux/module.h>
 #include <linux/scatterlist.h>
 #include <linux/ratelimit.h>
-#include <linux/dcache.h>
-#include <linux/namei.h>
 #include <crypto/skcipher.h>
 #include "fscrypt_private.h"
 
@@ -140,7 +138,7 @@ int fscrypt_crypt_block(const struct inode *inode, fscrypt_direction_t rw,
  *		multiple of the filesystem's block size.
  * @offs:      Byte offset within @page of the first block to encrypt.  Must be
  *		a multiple of the filesystem's block size.
- * @gfp_flags: Memory allocation flags
+ * @gfp_flags: Memory allocation flags.  See details below.
  *
  * A new bounce page is allocated, and the specified block(s) are encrypted into
  * it.  In the bounce page, the ciphertext block(s) will be located at the same
@@ -150,6 +148,11 @@ int fscrypt_crypt_block(const struct inode *inode, fscrypt_direction_t rw,
  *
  * This is for use by the filesystem's ->writepages() method.
  *
+ * The bounce page allocation is mempool-backed, so it will always succeed when
+ * @gfp_flags includes __GFP_DIRECT_RECLAIM, e.g. when it's GFP_NOFS.  However,
+ * only the first page of each bio can be allocated this way.  To prevent
+ * deadlocks, for any additional pages a mask like GFP_NOWAIT must be used.
+ *
  * Return: the new encrypted bounce page on success; an ERR_PTR() on failure
  */
 struct page *fscrypt_encrypt_pagecache_blocks(struct page *page,
@@ -286,54 +289,6 @@ int fscrypt_decrypt_block_inplace(const struct inode *inode, struct page *page,
 }
 EXPORT_SYMBOL(fscrypt_decrypt_block_inplace);
 
-/*
- * Validate dentries in encrypted directories to make sure we aren't potentially
- * caching stale dentries after a key has been added.
- */
-static int fscrypt_d_revalidate(struct dentry *dentry, unsigned int flags)
-{
-	struct dentry *dir;
-	int err;
-	int valid;
-
-	/*
-	 * Plaintext names are always valid, since fscrypt doesn't support
-	 * reverting to ciphertext names without evicting the directory's inode
-	 * -- which implies eviction of the dentries in the directory.
-	 */
-	if (!(dentry->d_flags & DCACHE_ENCRYPTED_NAME))
-		return 1;
-
-	/*
-	 * Ciphertext name; valid if the directory's key is still unavailable.
-	 *
-	 * Although fscrypt forbids rename() on ciphertext names, we still must
-	 * use dget_parent() here rather than use ->d_parent directly.  That's
-	 * because a corrupted fs image may contain directory hard links, which
-	 * the VFS handles by moving the directory's dentry tree in the dcache
-	 * each time ->lookup() finds the directory and it already has a dentry
-	 * elsewhere.  Thus ->d_parent can be changing, and we must safely grab
-	 * a reference to some ->d_parent to prevent it from being freed.
-	 */
-
-	if (flags & LOOKUP_RCU)
-		return -ECHILD;
-
-	dir = dget_parent(dentry);
-	err = fscrypt_get_encryption_info(d_inode(dir));
-	valid = !fscrypt_has_encryption_key(d_inode(dir));
-	dput(dir);
-
-	if (err < 0)
-		return err;
-
-	return valid;
-}
-
-const struct dentry_operations fscrypt_d_ops = {
-	.d_revalidate = fscrypt_d_revalidate,
-};
-
 /**
  * fscrypt_initialize() - allocate major buffers for fs encryption.
  * @cop_flags:  fscrypt operations flags