Linux 6.3 compat: idmapped mount API changes

Linux kernel 6.3 changed a bunch of APIs to use the dedicated idmap
type for mounts (struct mnt_idmap), we need to detect these changes
and make zfs work with the new APIs.

NOTE: This backport only includes the configure checks to detect
the 6.3 idmap API changes.  It does not include support for idmap.
When provided the idmap variable is ignored in most case in the
same way the user_ns argument was ignored.  This change is solely
to provide compatibility with the new interfaces.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Youzhong Yang <yyang@mathworks.com>
Closes #14682

module/os/linux/zfs/policy.c

@@ -124,7 +124,7 @@ secpolicy_vnode_any_access(const cred_t *cr, struct inode *ip, uid_t owner)
 	if (crgetuid(cr) == owner)
 		return (0);
 
-	if (zpl_inode_owner_or_capable(kcred->user_ns, ip))
+	if (zpl_inode_owner_or_capable(zfs_init_idmap, ip))
 		return (0);
 
 #if defined(CONFIG_USER_NS)

module/os/linux/zfs/zfs_ioctl_os.c

@@ -288,6 +288,8 @@ zfsdev_detach(void)
 #define	ZFS_DEBUG_STR	""
 #endif
 
+zidmap_t *zfs_init_idmap;
+
 static int __init
 openzfs_init(void)
 {
@@ -311,6 +313,8 @@ openzfs_init(void)
 	printk(KERN_NOTICE "ZFS: Posix ACLs disabled by kernel\n");
 #endif /* CONFIG_FS_POSIX_ACL */
 
+	zfs_init_idmap = (zidmap_t *)zfs_get_init_idmap();
+
 	return (0);
 }
 

module/os/linux/zfs/zfs_vnops_os.c

@@ -1675,8 +1675,7 @@ out:
  */
 /* ARGSUSED */
 int
-zfs_getattr_fast(struct user_namespace *user_ns, struct inode *ip,
-    struct kstat *sp)
+zfs_getattr_fast(zidmap_t *user_ns, struct inode *ip, struct kstat *sp)
 {
 	znode_t *zp = ITOZ(ip);
 	zfsvfs_t *zfsvfs = ITOZSB(ip);

module/os/linux/zfs/zpl_ctldir.c

@@ -101,7 +101,11 @@ zpl_root_readdir(struct file *filp, void *dirent, filldir_t filldir)
  */
 /* ARGSUSED */
 static int
-#ifdef HAVE_USERNS_IOPS_GETATTR
+#ifdef HAVE_IDMAP_IOPS_GETATTR
+zpl_root_getattr_impl(struct mnt_idmap *user_ns,
+    const struct path *path, struct kstat *stat, u32 request_mask,
+    unsigned int query_flags)
+#elif defined(HAVE_USERNS_IOPS_GETATTR)
 zpl_root_getattr_impl(struct user_namespace *user_ns,
     const struct path *path, struct kstat *stat, u32 request_mask,
     unsigned int query_flags)
@@ -112,8 +116,14 @@ zpl_root_getattr_impl(const struct path *path, struct kstat *stat,
 {
 	struct inode *ip = path->dentry->d_inode;
 
-#if defined(HAVE_GENERIC_FILLATTR_USERNS) && defined(HAVE_USERNS_IOPS_GETATTR)
+#if (defined(HAVE_USERNS_IOPS_GETATTR) || defined(HAVE_IDMAP_IOPS_GETATTR))
+#ifdef HAVE_GENERIC_FILLATTR_USERNS
 	generic_fillattr(user_ns, ip, stat);
+#elif defined(HAVE_GENERIC_FILLATTR_IDMAP)
+	generic_fillattr(user_ns, ip, stat);
+#else
+	(void) user_ns;
+#endif
 #else
 	generic_fillattr(ip, stat);
 #endif
@@ -304,6 +314,10 @@ static int
 zpl_snapdir_rename2(struct user_namespace *user_ns, struct inode *sdip,
     struct dentry *sdentry, struct inode *tdip, struct dentry *tdentry,
     unsigned int flags)
+#elif defined(HAVE_IOPS_RENAME_IDMAP)
+zpl_snapdir_rename2(struct mnt_idmap *user_ns, struct inode *sdip,
+    struct dentry *sdentry, struct inode *tdip, struct dentry *tdentry,
+    unsigned int flags)
 #else
 zpl_snapdir_rename2(struct inode *sdip, struct dentry *sdentry,
     struct inode *tdip, struct dentry *tdentry, unsigned int flags)
@@ -325,7 +339,9 @@ zpl_snapdir_rename2(struct inode *sdip, struct dentry *sdentry,
 	return (error);
 }
 
-#if !defined(HAVE_RENAME_WANTS_FLAGS) && !defined(HAVE_IOPS_RENAME_USERNS)
+#if (!defined(HAVE_RENAME_WANTS_FLAGS) && \
+	!defined(HAVE_IOPS_RENAME_USERNS) && \
+	!defined(HAVE_IOPS_RENAME_IDMAP))
 static int
 zpl_snapdir_rename(struct inode *sdip, struct dentry *sdentry,
     struct inode *tdip, struct dentry *tdentry)
@@ -352,6 +368,9 @@ static int
 #ifdef HAVE_IOPS_MKDIR_USERNS
 zpl_snapdir_mkdir(struct user_namespace *user_ns, struct inode *dip,
     struct dentry *dentry, umode_t mode)
+#elif defined(HAVE_IOPS_MKDIR_IDMAP)
+zpl_snapdir_mkdir(struct mnt_idmap *user_ns, struct inode *dip,
+    struct dentry *dentry, umode_t mode)
 #else
 zpl_snapdir_mkdir(struct inode *dip, struct dentry *dentry, umode_t mode)
 #endif
@@ -384,7 +403,11 @@ zpl_snapdir_mkdir(struct inode *dip, struct dentry *dentry, umode_t mode)
  */
 /* ARGSUSED */
 static int
-#ifdef HAVE_USERNS_IOPS_GETATTR
+#ifdef HAVE_IDMAP_IOPS_GETATTR
+zpl_snapdir_getattr_impl(struct mnt_idmap *user_ns,
+    const struct path *path, struct kstat *stat, u32 request_mask,
+    unsigned int query_flags)
+#elif defined(HAVE_USERNS_IOPS_GETATTR)
 zpl_snapdir_getattr_impl(struct user_namespace *user_ns,
     const struct path *path, struct kstat *stat, u32 request_mask,
     unsigned int query_flags)
@@ -397,8 +420,14 @@ zpl_snapdir_getattr_impl(const struct path *path, struct kstat *stat,
 	zfsvfs_t *zfsvfs = ITOZSB(ip);
 
 	ZPL_ENTER(zfsvfs);
-#if defined(HAVE_GENERIC_FILLATTR_USERNS) && defined(HAVE_USERNS_IOPS_GETATTR)
+#if (defined(HAVE_USERNS_IOPS_GETATTR) || defined(HAVE_IDMAP_IOPS_GETATTR))
+#ifdef HAVE_GENERIC_FILLATTR_USERNS
 	generic_fillattr(user_ns, ip, stat);
+#elif defined(HAVE_GENERIC_FILLATTR_IDMAP)
+	generic_fillattr(user_ns, ip, stat);
+#else
+	(void) user_ns;
+#endif
 #else
 	generic_fillattr(ip, stat);
 #endif
@@ -439,7 +468,9 @@ const struct file_operations zpl_fops_snapdir = {
 const struct inode_operations zpl_ops_snapdir = {
 	.lookup		= zpl_snapdir_lookup,
 	.getattr	= zpl_snapdir_getattr,
-#if defined(HAVE_RENAME_WANTS_FLAGS) || defined(HAVE_IOPS_RENAME_USERNS)
+#if (defined(HAVE_RENAME_WANTS_FLAGS) || \
+	defined(HAVE_IOPS_RENAME_USERNS) || \
+	defined(HAVE_IOPS_RENAME_IDMAP))
 	.rename		= zpl_snapdir_rename2,
 #else
 	.rename		= zpl_snapdir_rename,
@@ -530,6 +561,10 @@ static int
 zpl_shares_getattr_impl(struct user_namespace *user_ns,
     const struct path *path, struct kstat *stat, u32 request_mask,
     unsigned int query_flags)
+#elif defined(HAVE_IDMAP_IOPS_GETATTR)
+zpl_shares_getattr_impl(struct mnt_idmap *user_ns,
+    const struct path *path, struct kstat *stat, u32 request_mask,
+    unsigned int query_flags)
 #else
 zpl_shares_getattr_impl(const struct path *path, struct kstat *stat,
     u32 request_mask, unsigned int query_flags)
@@ -543,8 +578,14 @@ zpl_shares_getattr_impl(const struct path *path, struct kstat *stat,
 	ZPL_ENTER(zfsvfs);
 
 	if (zfsvfs->z_shares_dir == 0) {
-#if defined(HAVE_GENERIC_FILLATTR_USERNS) && defined(HAVE_USERNS_IOPS_GETATTR)
+#if (defined(HAVE_USERNS_IOPS_GETATTR) || defined(HAVE_IDMAP_IOPS_GETATTR))
+#ifdef HAVE_GENERIC_FILLATTR_USERNS
 		generic_fillattr(user_ns, path->dentry->d_inode, stat);
+#elif defined(HAVE_GENERIC_FILLATTR_IDMAP)
+		generic_fillattr(user_ns, path->dentry->d_inode, stat);
+#else
+		(void) user_ns;
+#endif
 #else
 		generic_fillattr(path->dentry->d_inode, stat);
 #endif
@@ -556,7 +597,7 @@ zpl_shares_getattr_impl(const struct path *path, struct kstat *stat,
 
 	error = -zfs_zget(zfsvfs, zfsvfs->z_shares_dir, &dzp);
 	if (error == 0) {
-#if defined(HAVE_GENERIC_FILLATTR_USERNS) && defined(HAVE_USERNS_IOPS_GETATTR)
+#if (defined(HAVE_USERNS_IOPS_GETATTR) || defined(HAVE_IDMAP_IOPS_GETATTR))
 		error = -zfs_getattr_fast(user_ns, ZTOI(dzp), stat);
 #else
 		error = -zfs_getattr_fast(kcred->user_ns, ZTOI(dzp), stat);

module/os/linux/zfs/zpl_file.c

@@ -978,7 +978,7 @@ __zpl_ioctl_setflags(struct inode *ip, uint32_t ioctl_flags, xvattr_t *xva)
 	    !capable(CAP_LINUX_IMMUTABLE))
 		return (-EPERM);
 
-	if (!zpl_inode_owner_or_capable(kcred->user_ns, ip))
+	if (!zpl_inode_owner_or_capable(zfs_init_idmap, ip))
 		return (-EACCES);
 
 	xva_init(xva);

module/os/linux/zfs/zpl_inode.c

@@ -131,6 +131,9 @@ static int
 #ifdef HAVE_IOPS_CREATE_USERNS
 zpl_create(struct user_namespace *user_ns, struct inode *dir,
     struct dentry *dentry, umode_t mode, bool flag)
+#elif defined(HAVE_IOPS_CREATE_IDMAP)
+zpl_create(struct mnt_idmap *user_ns, struct inode *dir,
+    struct dentry *dentry, umode_t mode, bool flag)
 #else
 zpl_create(struct inode *dir, struct dentry *dentry, umode_t mode, bool flag)
 #endif
@@ -174,6 +177,9 @@ static int
 #ifdef HAVE_IOPS_MKNOD_USERNS
 zpl_mknod(struct user_namespace *user_ns, struct inode *dir,
     struct dentry *dentry, umode_t mode,
+#elif defined(HAVE_IOPS_MKNOD_IDMAP)
+zpl_mknod(struct mnt_idmap *user_ns, struct inode *dir,
+    struct dentry *dentry, umode_t mode,
 #else
 zpl_mknod(struct inode *dir, struct dentry *dentry, umode_t mode,
 #endif
@@ -224,7 +230,10 @@ zpl_mknod(struct inode *dir, struct dentry *dentry, umode_t mode,
 
 #ifdef HAVE_TMPFILE
 static int
-#ifndef HAVE_TMPFILE_DENTRY
+#ifdef HAVE_TMPFILE_IDMAP
+zpl_tmpfile(struct mnt_idmap *userns, struct inode *dir,
+    struct file *file, umode_t mode)
+#elif !defined(HAVE_TMPFILE_DENTRY)
 zpl_tmpfile(struct user_namespace *userns, struct inode *dir,
     struct file *file, umode_t mode)
 #else
@@ -317,6 +326,9 @@ static int
 #ifdef HAVE_IOPS_MKDIR_USERNS
 zpl_mkdir(struct user_namespace *user_ns, struct inode *dir,
     struct dentry *dentry, umode_t mode)
+#elif defined(HAVE_IOPS_MKDIR_IDMAP)
+zpl_mkdir(struct mnt_idmap *user_ns, struct inode *dir,
+    struct dentry *dentry, umode_t mode)
 #else
 zpl_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
 #endif
@@ -386,6 +398,10 @@ static int
 zpl_getattr_impl(struct user_namespace *user_ns,
     const struct path *path, struct kstat *stat, u32 request_mask,
     unsigned int query_flags)
+#elif defined(HAVE_IDMAP_IOPS_GETATTR)
+zpl_getattr_impl(struct mnt_idmap *user_ns,
+    const struct path *path, struct kstat *stat, u32 request_mask,
+    unsigned int query_flags)
 #else
 zpl_getattr_impl(const struct path *path, struct kstat *stat, u32 request_mask,
     unsigned int query_flags)
@@ -402,7 +418,7 @@ zpl_getattr_impl(const struct path *path, struct kstat *stat, u32 request_mask,
 	 * XXX query_flags currently ignored.
 	 */
 
-#ifdef HAVE_USERNS_IOPS_GETATTR
+#if (defined(HAVE_USERNS_IOPS_GETATTR) || defined(HAVE_IDMAP_IOPS_GETATTR))
 	error = -zfs_getattr_fast(user_ns, ip, stat);
 #else
 	error = -zfs_getattr_fast(kcred->user_ns, ip, stat);
@@ -441,9 +457,12 @@ zpl_getattr_impl(const struct path *path, struct kstat *stat, u32 request_mask,
 ZPL_GETATTR_WRAPPER(zpl_getattr);
 
 static int
-#ifdef HAVE_SETATTR_PREPARE_USERNS
+#ifdef HAVE_USERNS_IOPS_SETATTR
 zpl_setattr(struct user_namespace *user_ns, struct dentry *dentry,
     struct iattr *ia)
+#elif defined(HAVE_IDMAP_IOPS_SETATTR)
+zpl_setattr(struct mnt_idmap *user_ns, struct dentry *dentry,
+    struct iattr *ia)
 #else
 zpl_setattr(struct dentry *dentry, struct iattr *ia)
 #endif
@@ -454,7 +473,13 @@ zpl_setattr(struct dentry *dentry, struct iattr *ia)
 	int error;
 	fstrans_cookie_t cookie;
 
-	error = zpl_setattr_prepare(kcred->user_ns, dentry, ia);
+#ifdef HAVE_SETATTR_PREPARE_USERNS
+	error = zpl_setattr_prepare(user_ns, dentry, ia);
+#elif defined(HAVE_SETATTR_PREPARE_IDMAP)
+	error = zpl_setattr_prepare(user_ns, dentry, ia);
+#else
+	error = zpl_setattr_prepare(zfs_init_idmap, dentry, ia);
+#endif
 	if (error)
 		return (error);
 
@@ -489,10 +514,14 @@ static int
 #ifdef HAVE_IOPS_RENAME_USERNS
 zpl_rename2(struct user_namespace *user_ns, struct inode *sdip,
     struct dentry *sdentry, struct inode *tdip, struct dentry *tdentry,
-    unsigned int flags)
+    unsigned int rflags)
+#elif defined(HAVE_IOPS_RENAME_IDMAP)
+zpl_rename2(struct mnt_idmap *user_ns, struct inode *sdip,
+    struct dentry *sdentry, struct inode *tdip, struct dentry *tdentry,
+    unsigned int rflags)
 #else
 zpl_rename2(struct inode *sdip, struct dentry *sdentry,
-    struct inode *tdip, struct dentry *tdentry, unsigned int flags)
+    struct inode *tdip, struct dentry *tdentry, unsigned int rflags)
 #endif
 {
 	cred_t *cr = CRED();
@@ -500,7 +529,7 @@ zpl_rename2(struct inode *sdip, struct dentry *sdentry,
 	fstrans_cookie_t cookie;
 
 	/* We don't have renameat2(2) support */
-	if (flags)
+	if (rflags)
 		return (-EINVAL);
 
 	crhold(cr);
@@ -514,7 +543,9 @@ zpl_rename2(struct inode *sdip, struct dentry *sdentry,
 	return (error);
 }
 
-#if !defined(HAVE_RENAME_WANTS_FLAGS) && !defined(HAVE_IOPS_RENAME_USERNS)
+#if !defined(HAVE_IOPS_RENAME_USERNS) && \
+	!defined(HAVE_RENAME_WANTS_FLAGS) && \
+	!defined(HAVE_IOPS_RENAME_IDMAP)
 static int
 zpl_rename(struct inode *sdip, struct dentry *sdentry,
     struct inode *tdip, struct dentry *tdentry)
@@ -527,6 +558,9 @@ static int
 #ifdef HAVE_IOPS_SYMLINK_USERNS
 zpl_symlink(struct user_namespace *user_ns, struct inode *dir,
     struct dentry *dentry, const char *name)
+#elif defined(HAVE_IOPS_SYMLINK_IDMAP)
+zpl_symlink(struct mnt_idmap *user_ns, struct inode *dir,
+    struct dentry *dentry, const char *name)
 #else
 zpl_symlink(struct inode *dir, struct dentry *dentry, const char *name)
 #endif
@@ -745,6 +779,8 @@ const struct inode_operations zpl_dir_inode_operations = {
 	.mknod		= zpl_mknod,
 #if defined(HAVE_RENAME_WANTS_FLAGS) || defined(HAVE_IOPS_RENAME_USERNS)
 	.rename		= zpl_rename2,
+#elif defined(HAVE_IOPS_RENAME_IDMAP)
+	.rename		= zpl_rename2,
 #else
 	.rename		= zpl_rename,
 #endif

module/os/linux/zfs/zpl_xattr.c

@@ -725,9 +725,11 @@ __zpl_xattr_user_get(struct inode *ip, const char *name,
 ZPL_XATTR_GET_WRAPPER(zpl_xattr_user_get);
 
 static int
-__zpl_xattr_user_set(struct inode *ip, const char *name,
+__zpl_xattr_user_set(zidmap_t *user_ns,
+    struct inode *ip, const char *name,
     const void *value, size_t size, int flags)
 {
+	(void) user_ns;
 	char *xattr_name;
 	int error;
 	/* xattr_resolve_name will do this for us if this is defined */
@@ -794,9 +796,11 @@ __zpl_xattr_trusted_get(struct inode *ip, const char *name,
 ZPL_XATTR_GET_WRAPPER(zpl_xattr_trusted_get);
 
 static int
-__zpl_xattr_trusted_set(struct inode *ip, const char *name,
+__zpl_xattr_trusted_set(zidmap_t *user_ns,
+    struct inode *ip, const char *name,
     const void *value, size_t size, int flags)
 {
+	(void) user_ns;
 	char *xattr_name;
 	int error;
 
@@ -863,9 +867,11 @@ __zpl_xattr_security_get(struct inode *ip, const char *name,
 ZPL_XATTR_GET_WRAPPER(zpl_xattr_security_get);
 
 static int
-__zpl_xattr_security_set(struct inode *ip, const char *name,
+__zpl_xattr_security_set(zidmap_t *user_ns,
+    struct inode *ip, const char *name,
     const void *value, size_t size, int flags)
 {
+	(void) user_ns;
 	char *xattr_name;
 	int error;
 	/* xattr_resolve_name will do this for us if this is defined */
@@ -889,7 +895,7 @@ zpl_xattr_security_init_impl(struct inode *ip, const struct xattr *xattrs,
 	int error = 0;
 
 	for (xattr = xattrs; xattr->name != NULL; xattr++) {
-		error = __zpl_xattr_security_set(ip,
+		error = __zpl_xattr_security_set(NULL, ip,
 		    xattr->name, xattr->value, xattr->value_len, 0);
 
 		if (error < 0)
@@ -1004,6 +1010,9 @@ int
 #ifdef HAVE_SET_ACL_USERNS
 zpl_set_acl(struct user_namespace *userns, struct inode *ip,
     struct posix_acl *acl, int type)
+#elif defined(HAVE_SET_ACL_IDMAP_DENTRY)
+zpl_set_acl(struct mnt_idmap *userns, struct dentry *dentry,
+    struct posix_acl *acl, int type)
 #elif defined(HAVE_SET_ACL_USERNS_DENTRY_ARG2)
 zpl_set_acl(struct user_namespace *userns, struct dentry *dentry,
     struct posix_acl *acl, int type)
@@ -1013,6 +1022,8 @@ zpl_set_acl(struct inode *ip, struct posix_acl *acl, int type)
 {
 #ifdef HAVE_SET_ACL_USERNS_DENTRY_ARG2
 	return (zpl_set_acl_impl(d_inode(dentry), acl, type));
+#elif defined(HAVE_SET_ACL_IDMAP_DENTRY)
+	return (zpl_set_acl_impl(d_inode(dentry), acl, type));
 #else
 	return (zpl_set_acl_impl(ip, acl, type));
 #endif /* HAVE_SET_ACL_USERNS_DENTRY_ARG2 */
@@ -1256,7 +1267,8 @@ __zpl_xattr_acl_get_default(struct inode *ip, const char *name,
 ZPL_XATTR_GET_WRAPPER(zpl_xattr_acl_get_default);
 
 static int
-__zpl_xattr_acl_set_access(struct inode *ip, const char *name,
+__zpl_xattr_acl_set_access(zidmap_t *mnt_ns,
+    struct inode *ip, const char *name,
     const void *value, size_t size, int flags)
 {
 	struct posix_acl *acl;
@@ -1270,8 +1282,14 @@ __zpl_xattr_acl_set_access(struct inode *ip, const char *name,
 	if (ITOZSB(ip)->z_acl_type != ZFS_ACLTYPE_POSIX)
 		return (-EOPNOTSUPP);
 
-	if (!zpl_inode_owner_or_capable(kcred->user_ns, ip))
+#if defined(HAVE_XATTR_SET_USERNS) || defined(HAVE_XATTR_SET_IDMAP)
+	if (!zpl_inode_owner_or_capable(mnt_ns, ip))
 		return (-EPERM);
+#else
+	(void) mnt_ns;
+	if (!zpl_inode_owner_or_capable(zfs_init_idmap, ip))
+		return (-EPERM);
+#endif
 
 	if (value) {
 		acl = zpl_acl_from_xattr(value, size);
@@ -1295,7 +1313,8 @@ __zpl_xattr_acl_set_access(struct inode *ip, const char *name,
 ZPL_XATTR_SET_WRAPPER(zpl_xattr_acl_set_access);
 
 static int
-__zpl_xattr_acl_set_default(struct inode *ip, const char *name,
+__zpl_xattr_acl_set_default(zidmap_t *mnt_ns,
+    struct inode *ip, const char *name,
     const void *value, size_t size, int flags)
 {
 	struct posix_acl *acl;
@@ -1309,8 +1328,14 @@ __zpl_xattr_acl_set_default(struct inode *ip, const char *name,
 	if (ITOZSB(ip)->z_acl_type != ZFS_ACLTYPE_POSIX)
 		return (-EOPNOTSUPP);
 
-	if (!zpl_inode_owner_or_capable(kcred->user_ns, ip))
+#if defined(HAVE_XATTR_SET_USERNS) || defined(HAVE_XATTR_SET_IDMAP)
+	if (!zpl_inode_owner_or_capable(mnt_ns, ip))
 		return (-EPERM);
+#else
+	(void) mnt_ns;
+	if (!zpl_inode_owner_or_capable(zfs_init_idmap, ip))
+		return (-EPERM);
+#endif
 
 	if (value) {
 		acl = zpl_acl_from_xattr(value, size);