fsverity: optimize fsverity_file_open() on non-verity files

Make fsverity_file_open() an inline function that does the IS_VERITY()
check, then (if needed) calls __fsverity_file_open() to do the real
work.  This reduces the overhead on non-verity files.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Acked-by: Dave Chinner <dchinner@redhat.com>
Link: https://lore.kernel.org/r/20221214224304.145712-2-ebiggers@kernel.org
This commit is contained in:
Eric Biggers 2022-12-14 14:43:01 -08:00
parent 88603b6dc4
commit a6528a960b
2 changed files with 25 additions and 21 deletions

View File

@ -325,24 +325,8 @@ out_free_desc:
return err;
}
/**
* fsverity_file_open() - prepare to open a verity file
* @inode: the inode being opened
* @filp: the struct file being set up
*
* When opening a verity file, deny the open if it is for writing. Otherwise,
* set up the inode's ->i_verity_info if not already done.
*
* When combined with fscrypt, this must be called after fscrypt_file_open().
* Otherwise, we won't have the key set up to decrypt the verity metadata.
*
* Return: 0 on success, -errno on failure
*/
int fsverity_file_open(struct inode *inode, struct file *filp)
int __fsverity_file_open(struct inode *inode, struct file *filp)
{
if (!IS_VERITY(inode))
return 0;
if (filp->f_mode & FMODE_WRITE) {
pr_debug("Denying opening verity file (ino %lu) for write\n",
inode->i_ino);
@ -351,7 +335,7 @@ int fsverity_file_open(struct inode *inode, struct file *filp)
return ensure_verity_info(inode);
}
EXPORT_SYMBOL_GPL(fsverity_file_open);
EXPORT_SYMBOL_GPL(__fsverity_file_open);
/**
* fsverity_prepare_setattr() - prepare to change a verity inode's attributes

View File

@ -148,7 +148,7 @@ int fsverity_get_digest(struct inode *inode,
/* open.c */
int fsverity_file_open(struct inode *inode, struct file *filp);
int __fsverity_file_open(struct inode *inode, struct file *filp);
int fsverity_prepare_setattr(struct dentry *dentry, struct iattr *attr);
void fsverity_cleanup_inode(struct inode *inode);
@ -193,9 +193,9 @@ static inline int fsverity_get_digest(struct inode *inode,
/* open.c */
static inline int fsverity_file_open(struct inode *inode, struct file *filp)
static inline int __fsverity_file_open(struct inode *inode, struct file *filp)
{
return IS_VERITY(inode) ? -EOPNOTSUPP : 0;
return -EOPNOTSUPP;
}
static inline int fsverity_prepare_setattr(struct dentry *dentry,
@ -254,4 +254,24 @@ static inline bool fsverity_active(const struct inode *inode)
return fsverity_get_info(inode) != NULL;
}
/**
* fsverity_file_open() - prepare to open a verity file
* @inode: the inode being opened
* @filp: the struct file being set up
*
* When opening a verity file, deny the open if it is for writing. Otherwise,
* set up the inode's ->i_verity_info if not already done.
*
* When combined with fscrypt, this must be called after fscrypt_file_open().
* Otherwise, we won't have the key set up to decrypt the verity metadata.
*
* Return: 0 on success, -errno on failure
*/
static inline int fsverity_file_open(struct inode *inode, struct file *filp)
{
if (IS_VERITY(inode))
return __fsverity_file_open(inode, filp);
return 0;
}
#endif /* _LINUX_FSVERITY_H */