[PATCH v4 05/15] fs/fuse: support idmap for mkdir/mknod/symlink/create/tmpfile

Alexander Mikhalitsyn
2024-09-03T15:17:00Z

We have all the infrastructure in place, we just need
to pass an idmapping here.

Cc: Christian Brauner <brauner@kernel.org>
Cc: Seth Forshee <sforshee@kernel.org>
Cc: Miklos Szeredi <miklos@szeredi.hu>
Cc: Amir Goldstein <amir73il@gmail.com>
Cc: Bernd Schubert <bschubert@ddn.com>
Cc: <linux-fsdevel@vger.kernel.org>
Signed-off-by: Alexander Mikhalitsyn <aleksandr.mikhalitsyn@canonical.com>
Reviewed-by: Christian Brauner <brauner@kernel.org>
---
v4:
- pass idmapping to fuse_simple_request()
---
fs/fuse/dir.c | 37 +++++++++++++++++++------------------
1 file changed, 19 insertions(+), 18 deletions(-)

diff --git a/fs/fuse/dir.c b/fs/fuse/dir.c
index b0b57f383889..19538b1c12e2 100644
--- a/fs/fuse/dir.c
+++ b/fs/fuse/dir.c
@@ -614,9 +614,9 @@ static void free_ext_value(struct fuse_args *args)
* If the filesystem doesn't support this, then fall back to separate
* 'mknod' + 'open' requests.
*/
-static int fuse_create_open(struct inode *dir, struct dentry *entry,
- struct file *file, unsigned int flags,
- umode_t mode, u32 opcode)
+static int fuse_create_open(struct mnt_idmap *idmap, struct inode *dir,
+ struct dentry *entry, struct file *file,
+ unsigned int flags, umode_t mode, u32 opcode)
{
int err;
struct inode *inode;
@@ -673,11 +673,11 @@ static int fuse_create_open(struct inode *dir, struct dentry *entry,
args.out_args[1].size = sizeof(*outopenp);
args.out_args[1].value = outopenp;

- err = get_create_ext(&nop_mnt_idmap, &args, dir, entry, mode);
+ err = get_create_ext(idmap, &args, dir, entry, mode);
if (err)
goto out_put_forget_req;

- err = fuse_simple_request(NULL, fm, &args);
+ err = fuse_simple_request(idmap, fm, &args);
free_ext_value(&args);
if (err)
goto out_free_ff;
@@ -734,6 +734,7 @@ static int fuse_atomic_open(struct inode *dir, struct dentry *entry,
umode_t mode)
{
int err;
+ struct mnt_idmap *idmap = file_mnt_idmap(file);
struct fuse_conn *fc = get_fuse_conn(dir);
struct dentry *res = NULL;

@@ -758,7 +759,7 @@ static int fuse_atomic_open(struct inode *dir, struct dentry *entry,
if (fc->no_create)
goto mknod;

- err = fuse_create_open(dir, entry, file, flags, mode, FUSE_CREATE);
+ err = fuse_create_open(idmap, dir, entry, file, flags, mode, FUSE_CREATE);
if (err == -ENOSYS) {
fc->no_create = 1;
goto mknod;
@@ -769,7 +770,7 @@ static int fuse_atomic_open(struct inode *dir, struct dentry *entry,
return err;

mknod:
- err = fuse_mknod(&nop_mnt_idmap, dir, entry, mode, 0);
+ err = fuse_mknod(idmap, dir, entry, mode, 0);
if (err)
goto out_dput;
no_open:
@@ -779,9 +780,9 @@ static int fuse_atomic_open(struct inode *dir, struct dentry *entry,
/*
* Code shared between mknod, mkdir, symlink and link
*/
-static int create_new_entry(struct fuse_mount *fm, struct fuse_args *args,
- struct inode *dir, struct dentry *entry,
- umode_t mode)
+static int create_new_entry(struct mnt_idmap *idmap, struct fuse_mount *fm,
+ struct fuse_args *args, struct inode *dir,
+ struct dentry *entry, umode_t mode)
{
struct fuse_entry_out outarg;
struct inode *inode;
@@ -803,12 +804,12 @@ static int create_new_entry(struct fuse_mount *fm, struct fuse_args *args,
args->out_args[0].value = &outarg;

if (args->opcode != FUSE_LINK) {
- err = get_create_ext(&nop_mnt_idmap, args, dir, entry, mode);
+ err = get_create_ext(idmap, args, dir, entry, mode);
if (err)
goto out_put_forget_req;
}

- err = fuse_simple_request(NULL, fm, args);
+ err = fuse_simple_request(idmap, fm, args);
free_ext_value(args);
if (err)
goto out_put_forget_req;
@@ -869,13 +870,13 @@ static int fuse_mknod(struct mnt_idmap *idmap, struct inode *dir,
args.in_args[0].value = &inarg;
args.in_args[1].size = entry->d_name.len + 1;
args.in_args[1].value = entry->d_name.name;
- return create_new_entry(fm, &args, dir, entry, mode);
+ return create_new_entry(idmap, fm, &args, dir, entry, mode);
}

static int fuse_create(struct mnt_idmap *idmap, struct inode *dir,
struct dentry *entry, umode_t mode, bool excl)
{
- return fuse_mknod(&nop_mnt_idmap, dir, entry, mode, 0);
+ return fuse_mknod(idmap, dir, entry, mode, 0);
}

static int fuse_tmpfile(struct mnt_idmap *idmap, struct inode *dir,
@@ -887,7 +888,7 @@ static int fuse_tmpfile(struct mnt_idmap *idmap, struct inode *dir,
if (fc->no_tmpfile)
return -EOPNOTSUPP;

- err = fuse_create_open(dir, file->f_path.dentry, file, file->f_flags, mode, FUSE_TMPFILE);
+ err = fuse_create_open(idmap, dir, file->f_path.dentry, file, file->f_flags, mode, FUSE_TMPFILE);
if (err == -ENOSYS) {
fc->no_tmpfile = 1;
err = -EOPNOTSUPP;
@@ -914,7 +915,7 @@ static int fuse_mkdir(struct mnt_idmap *idmap, struct inode *dir,
args.in_args[0].value = &inarg;
args.in_args[1].size = entry->d_name.len + 1;
args.in_args[1].value = entry->d_name.name;
- return create_new_entry(fm, &args, dir, entry, S_IFDIR);
+ return create_new_entry(idmap, fm, &args, dir, entry, S_IFDIR);
}

static int fuse_symlink(struct mnt_idmap *idmap, struct inode *dir,
@@ -930,7 +931,7 @@ static int fuse_symlink(struct mnt_idmap *idmap, struct inode *dir,
args.in_args[0].value = entry->d_name.name;
args.in_args[1].size = len;
args.in_args[1].value = link;
- return create_new_entry(fm, &args, dir, entry, S_IFLNK);
+ return create_new_entry(idmap, fm, &args, dir, entry, S_IFLNK);
}

void fuse_flush_time_update(struct inode *inode)
@@ -1124,7 +1125,7 @@ static int fuse_link(struct dentry *entry, struct inode *newdir,
args.in_args[0].value = &inarg;
args.in_args[1].size = newent->d_name.len + 1;
args.in_args[1].value = newent->d_name.name;
- err = create_new_entry(fm, &args, newdir, newent, inode->i_mode);
+ err = create_new_entry(NULL, fm, &args, newdir, newent, inode->i_mode);
if (!err)
fuse_update_ctime_in_cache(inode);
else if (err == -EINTR)
--
2.34.1