Merge tag 'fuse-update-6.12' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse

Pull fuse updates from Miklos Szeredi:

 - Add support for idmapped fuse mounts (Alexander Mikhalitsyn)

 - Add optimization when checking for writeback (yangyun)

 - Add tracepoints (Josef Bacik)

 - Clean up writeback code (Joanne Koong)

 - Clean up request queuing (me)

 - Misc fixes

* tag 'fuse-update-6.12' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse: (32 commits)
  fuse: use exclusive lock when FUSE_I_CACHE_IO_MODE is set
  fuse: clear FR_PENDING if abort is detected when sending request
  fs/fuse: convert to use invalid_mnt_idmap
  fs/mnt_idmapping: introduce an invalid_mnt_idmap
  fs/fuse: introduce and use fuse_simple_idmap_request() helper
  fs/fuse: fix null-ptr-deref when checking SB_I_NOIDMAP flag
  fuse: allow O_PATH fd for FUSE_DEV_IOC_BACKING_OPEN
  virtio_fs: allow idmapped mounts
  fuse: allow idmapped mounts
  fuse: warn if fuse_access is called when idmapped mounts are allowed
  fuse: handle idmappings properly in ->write_iter()
  fuse: support idmapped ->rename op
  fuse: support idmapped ->set_acl
  fuse: drop idmap argument from __fuse_get_acl
  fuse: support idmapped ->setattr op
  fuse: support idmapped ->permission inode op
  fuse: support idmapped getattr inode op
  fuse: support idmap for mkdir/mknod/symlink/create/tmpfile
  fuse: support idmapped FUSE_EXT_GROUPS
  fuse: add an idmap argument to fuse_simple_request
  ...

1 files changed, 20 insertions, 2 deletions

diff --git a/fs/mnt_idmapping.c b/fs/mnt_idmapping.c
index 79491663dbc0..7b1df8cc2821 100644
--- a/fs/mnt_idmapping.c
+++ b/fs/mnt_idmapping.c
@@ -32,6 +32,15 @@ struct mnt_idmap nop_mnt_idmap = {
 };
 EXPORT_SYMBOL_GPL(nop_mnt_idmap);
 
+/*
+ * Carries the invalid idmapping of a full 0-4294967295 {g,u}id range.
+ * This means that all {g,u}ids are mapped to INVALID_VFS{G,U}ID.
+ */
+struct mnt_idmap invalid_mnt_idmap = {
+	.count	= REFCOUNT_INIT(1),
+};
+EXPORT_SYMBOL_GPL(invalid_mnt_idmap);
+
 /**
  * initial_idmapping - check whether this is the initial mapping
  * @ns: idmapping to check
@@ -75,6 +84,8 @@ vfsuid_t make_vfsuid(struct mnt_idmap *idmap,
 
 	if (idmap == &nop_mnt_idmap)
 		return VFSUIDT_INIT(kuid);
+	if (idmap == &invalid_mnt_idmap)
+		return INVALID_VFSUID;
 	if (initial_idmapping(fs_userns))
 		uid = __kuid_val(kuid);
 	else
@@ -112,6 +123,8 @@ vfsgid_t make_vfsgid(struct mnt_idmap *idmap,
 
 	if (idmap == &nop_mnt_idmap)
 		return VFSGIDT_INIT(kgid);
+	if (idmap == &invalid_mnt_idmap)
+		return INVALID_VFSGID;
 	if (initial_idmapping(fs_userns))
 		gid = __kgid_val(kgid);
 	else
@@ -140,6 +153,8 @@ kuid_t from_vfsuid(struct mnt_idmap *idmap,
 
 	if (idmap == &nop_mnt_idmap)
 		return AS_KUIDT(vfsuid);
+	if (idmap == &invalid_mnt_idmap)
+		return INVALID_UID;
 	uid = map_id_up(&idmap->uid_map, __vfsuid_val(vfsuid));
 	if (uid == (uid_t)-1)
 		return INVALID_UID;
@@ -167,6 +182,8 @@ kgid_t from_vfsgid(struct mnt_idmap *idmap,
 
 	if (idmap == &nop_mnt_idmap)
 		return AS_KGIDT(vfsgid);
+	if (idmap == &invalid_mnt_idmap)
+		return INVALID_GID;
 	gid = map_id_up(&idmap->gid_map, __vfsgid_val(vfsgid));
 	if (gid == (gid_t)-1)
 		return INVALID_GID;
@@ -296,7 +313,7 @@ struct mnt_idmap *alloc_mnt_idmap(struct user_namespace *mnt_userns)
  */
 struct mnt_idmap *mnt_idmap_get(struct mnt_idmap *idmap)
 {
-	if (idmap != &nop_mnt_idmap)
+	if (idmap != &nop_mnt_idmap && idmap != &invalid_mnt_idmap)
 		refcount_inc(&idmap->count);
 
 	return idmap;
@@ -312,7 +329,8 @@ EXPORT_SYMBOL_GPL(mnt_idmap_get);
  */
 void mnt_idmap_put(struct mnt_idmap *idmap)
 {
-	if (idmap != &nop_mnt_idmap && refcount_dec_and_test(&idmap->count))
+	if (idmap != &nop_mnt_idmap && idmap != &invalid_mnt_idmap &&
+	    refcount_dec_and_test(&idmap->count))
 		free_mnt_idmap(idmap);
 }
 EXPORT_SYMBOL_GPL(mnt_idmap_put);