fs: use a helper for opening kernel internal files

cachefiles uses kernel_open_tmpfile() to open kernel internal tmpfile
without accounting for nr_files.

cachefiles uses open_with_fake_path() for the same reason without the
need for a fake path.

Fork open_with_fake_path() to kernel_file_open() which only does the
noaccount part and use it in cachefiles.

Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Message-Id: <20230615112229.2143178-3-amir73il@gmail.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
This commit is contained in:
Amir Goldstein 2023-06-15 14:22:26 +03:00 committed by Christian Brauner
parent d56e0ddb8f
commit cbb0b9d4bb
No known key found for this signature in database
GPG Key ID: 91C61BC06578DCA2
3 changed files with 37 additions and 2 deletions

View File

@ -560,8 +560,8 @@ static bool cachefiles_open_file(struct cachefiles_object *object,
*/
path.mnt = cache->mnt;
path.dentry = dentry;
file = open_with_fake_path(&path, O_RDWR | O_LARGEFILE | O_DIRECT,
d_backing_inode(dentry), cache->cache_cred);
file = kernel_file_open(&path, O_RDWR | O_LARGEFILE | O_DIRECT,
d_backing_inode(dentry), cache->cache_cred);
if (IS_ERR(file)) {
trace_cachefiles_vfs_error(object, d_backing_inode(dentry),
PTR_ERR(file),

View File

@ -1116,6 +1116,39 @@ struct file *dentry_create(const struct path *path, int flags, umode_t mode,
}
EXPORT_SYMBOL(dentry_create);
/**
* kernel_file_open - open a file for kernel internal use
* @path: path of the file to open
* @flags: open flags
* @inode: the inode
* @cred: credentials for open
*
* Open a file for use by in-kernel consumers. The file is not accounted
* against nr_files and must not be installed into the file descriptor
* table.
*
* Return: Opened file on success, an error pointer on failure.
*/
struct file *kernel_file_open(const struct path *path, int flags,
struct inode *inode, const struct cred *cred)
{
struct file *f;
int error;
f = alloc_empty_file_noaccount(flags, cred);
if (IS_ERR(f))
return f;
f->f_path = *path;
error = do_dentry_open(f, inode, NULL);
if (error) {
fput(f);
f = ERR_PTR(error);
}
return f;
}
EXPORT_SYMBOL_GPL(kernel_file_open);
struct file *open_with_fake_path(const struct path *path, int flags,
struct inode *inode, const struct cred *cred)
{

View File

@ -1676,6 +1676,8 @@ struct file *kernel_tmpfile_open(struct mnt_idmap *idmap,
const struct path *parentpath,
umode_t mode, int open_flag,
const struct cred *cred);
struct file *kernel_file_open(const struct path *path, int flags,
struct inode *inode, const struct cred *cred);
int vfs_mkobj(struct dentry *, umode_t,
int (*f)(struct dentry *, umode_t, void *),