Merge tag 'vfs-6.10.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs

Pull misc vfs updates from Christian Brauner:
 "This contains the usual miscellaneous features, cleanups, and fixes
  for vfs and individual fses.

  Features:

   - Free up FMODE_* bits. I've freed up bits 6, 7, 8, and 24. That
     means we now have six free FMODE_* bits in total (but bit #6
     already got used for FMODE_WRITE_RESTRICTED)

   - Add FOP_HUGE_PAGES flag (follow-up to FMODE_* cleanup)

   - Add fd_raw cleanup class so we can make use of automatic cleanup
     provided by CLASS(fd_raw, f)(fd) for O_PATH fds as well

   - Optimize seq_puts()

   - Simplify __seq_puts()

   - Add new anon_inode_getfile_fmode() api to allow specifying f_mode
     instead of open-coding it in multiple places

   - Annotate struct file_handle with __counted_by() and use
     struct_size()

   - Warn in get_file() whether f_count resurrection from zero is
     attempted (epoll/drm discussion)

   - Folio-sophize aio

   - Export the subvolume id in statx() for both btrfs and bcachefs

   - Relax linkat(AT_EMPTY_PATH) requirements

   - Add F_DUPFD_QUERY fcntl() allowing to compare two file descriptors
     for dup*() equality replacing kcmp()

  Cleanups:

   - Compile out swapfile inode checks when swap isn't enabled

   - Use (1 << n) notation for FMODE_* bitshifts for clarity

   - Remove redundant variable assignment in fs/direct-io

   - Cleanup uses of strncpy in orangefs

   - Speed up and cleanup writeback

   - Move fsparam_string_empty() helper into header since it's currently
     open-coded in multiple places

   - Add kernel-doc comments to proc_create_net_data_write()

   - Don't needlessly read dentry->d_flags twice

  Fixes:

   - Fix out-of-range warning in nilfs2

   - Fix ecryptfs overflow due to wrong encryption packet size
     calculation

   - Fix overly long line in xfs file_operations (follow-up to FMODE_*
     cleanup)

   - Don't raise FOP_BUFFER_{R,W}ASYNC for directories in xfs (follow-up
     to FMODE_* cleanup)

   - Don't call xfs_file_open from xfs_dir_open (follow-up to FMODE_*
     cleanup)

   - Fix stable offset api to prevent endless loops

   - Fix afs file server rotations

   - Prevent xattr node from overflowing the eraseblock in jffs2

   - Move fdinfo PTRACE_MODE_READ procfs check into the .permission()
     operation instead of .open() operation since this caused userspace
     regressions"

* tag 'vfs-6.10.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (39 commits)
  afs: Fix fileserver rotation getting stuck
  selftests: add F_DUPDFD_QUERY selftests
  fcntl: add F_DUPFD_QUERY fcntl()
  file: add fd_raw cleanup class
  fs: WARN when f_count resurrection is attempted
  seq_file: Simplify __seq_puts()
  seq_file: Optimize seq_puts()
  proc: Move fdinfo PTRACE_MODE_READ check into the inode .permission operation
  fs: Create anon_inode_getfile_fmode()
  xfs: don't call xfs_file_open from xfs_dir_open
  xfs: drop fop_flags for directories
  xfs: fix overly long line in the file_operations
  shmem: Fix shmem_rename2()
  libfs: Add simple_offset_rename() API
  libfs: Fix simple_offset_rename_exchange()
  jffs2: prevent xattr node from overflowing the eraseblock
  vfs, swap: compile out IS_SWAPFILE() on swapless configs
  vfs: relax linkat() AT_EMPTY_PATH - aka flink() - requirements
  fs/direct-io: remove redundant assignment to variable retval
  fs/dcache: Re-use value stored to dentry->d_flags instead of re-reading
  ...

9 files changed, 82 insertions, 50 deletions

diff --git a/include/linux/anon_inodes.h b/include/linux/anon_inodes.h
index 93a5f16d03f3..edef565c2a1a 100644
--- a/include/linux/anon_inodes.h
+++ b/include/linux/anon_inodes.h
@@ -9,12 +9,17 @@
 #ifndef _LINUX_ANON_INODES_H
 #define _LINUX_ANON_INODES_H
 
+#include <linux/types.h>
+
 struct file_operations;
 struct inode;
 
 struct file *anon_inode_getfile(const char *name,
 				const struct file_operations *fops,
 				void *priv, int flags);
+struct file *anon_inode_getfile_fmode(const char *name,
+				const struct file_operations *fops,
+				void *priv, int flags, fmode_t f_mode);
 struct file *anon_inode_create_getfile(const char *name,
 				       const struct file_operations *fops,
 				       void *priv, int flags,
diff --git a/include/linux/file.h b/include/linux/file.h
index 169692cb1906..45d0f4800abd 100644
--- a/include/linux/file.h
+++ b/include/linux/file.h
@@ -84,6 +84,7 @@ static inline void fdput_pos(struct fd f)
 }
 
 DEFINE_CLASS(fd, struct fd, fdput(_T), fdget(fd), int fd)
+DEFINE_CLASS(fd_raw, struct fd, fdput(_T), fdget_raw(fd), int fd)
 
 extern int f_dupfd(unsigned int from, struct file *file, unsigned flags);
 extern int replace_fd(unsigned fd, struct file *file, unsigned flags);
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 8dfd53b52744..de946a1fd845 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -110,23 +110,26 @@ typedef int (dio_iodone_t)(struct kiocb *iocb, loff_t offset,
  */
 
 /* file is open for reading */
-#define FMODE_READ		((__force fmode_t)0x1)
+#define FMODE_READ		((__force fmode_t)(1 << 0))
 /* file is open for writing */
-#define FMODE_WRITE		((__force fmode_t)0x2)
+#define FMODE_WRITE		((__force fmode_t)(1 << 1))
 /* file is seekable */
-#define FMODE_LSEEK		((__force fmode_t)0x4)
+#define FMODE_LSEEK		((__force fmode_t)(1 << 2))
 /* file can be accessed using pread */
-#define FMODE_PREAD		((__force fmode_t)0x8)
+#define FMODE_PREAD		((__force fmode_t)(1 << 3))
 /* file can be accessed using pwrite */
-#define FMODE_PWRITE		((__force fmode_t)0x10)
+#define FMODE_PWRITE		((__force fmode_t)(1 << 4))
 /* File is opened for execution with sys_execve / sys_uselib */
-#define FMODE_EXEC		((__force fmode_t)0x20)
+#define FMODE_EXEC		((__force fmode_t)(1 << 5))
 /* File writes are restricted (block device specific) */
-#define FMODE_WRITE_RESTRICTED  ((__force fmode_t)0x40)
+#define FMODE_WRITE_RESTRICTED	((__force fmode_t)(1 << 6))
+
+/* FMODE_* bits 7 to 8 */
+
 /* 32bit hashes as llseek() offset (for directories) */
-#define FMODE_32BITHASH         ((__force fmode_t)0x200)
+#define FMODE_32BITHASH         ((__force fmode_t)(1 << 9))
 /* 64bit hashes as llseek() offset (for directories) */
-#define FMODE_64BITHASH         ((__force fmode_t)0x400)
+#define FMODE_64BITHASH         ((__force fmode_t)(1 << 10))
 
 /*
  * Don't update ctime and mtime.
@@ -134,60 +137,53 @@ typedef int (dio_iodone_t)(struct kiocb *iocb, loff_t offset,
  * Currently a special hack for the XFS open_by_handle ioctl, but we'll
  * hopefully graduate it to a proper O_CMTIME flag supported by open(2) soon.
  */
-#define FMODE_NOCMTIME		((__force fmode_t)0x800)
+#define FMODE_NOCMTIME		((__force fmode_t)(1 << 11))
 
 /* Expect random access pattern */
-#define FMODE_RANDOM		((__force fmode_t)0x1000)
+#define FMODE_RANDOM		((__force fmode_t)(1 << 12))
 
 /* File is huge (eg. /dev/mem): treat loff_t as unsigned */
-#define FMODE_UNSIGNED_OFFSET	((__force fmode_t)0x2000)
+#define FMODE_UNSIGNED_OFFSET	((__force fmode_t)(1 << 13))
 
 /* File is opened with O_PATH; almost nothing can be done with it */
-#define FMODE_PATH		((__force fmode_t)0x4000)
+#define FMODE_PATH		((__force fmode_t)(1 << 14))
 
 /* File needs atomic accesses to f_pos */
-#define FMODE_ATOMIC_POS	((__force fmode_t)0x8000)
+#define FMODE_ATOMIC_POS	((__force fmode_t)(1 << 15))
 /* Write access to underlying fs */
-#define FMODE_WRITER		((__force fmode_t)0x10000)
+#define FMODE_WRITER		((__force fmode_t)(1 << 16))
 /* Has read method(s) */
-#define FMODE_CAN_READ          ((__force fmode_t)0x20000)
+#define FMODE_CAN_READ          ((__force fmode_t)(1 << 17))
 /* Has write method(s) */
-#define FMODE_CAN_WRITE         ((__force fmode_t)0x40000)
+#define FMODE_CAN_WRITE         ((__force fmode_t)(1 << 18))
 
-#define FMODE_OPENED		((__force fmode_t)0x80000)
-#define FMODE_CREATED		((__force fmode_t)0x100000)
+#define FMODE_OPENED		((__force fmode_t)(1 << 19))
+#define FMODE_CREATED		((__force fmode_t)(1 << 20))
 
 /* File is stream-like */
-#define FMODE_STREAM		((__force fmode_t)0x200000)
+#define FMODE_STREAM		((__force fmode_t)(1 << 21))
 
 /* File supports DIRECT IO */
-#define	FMODE_CAN_ODIRECT	((__force fmode_t)0x400000)
+#define	FMODE_CAN_ODIRECT	((__force fmode_t)(1 << 22))
 
-#define	FMODE_NOREUSE		((__force fmode_t)0x800000)
+#define	FMODE_NOREUSE		((__force fmode_t)(1 << 23))
 
-/* File supports non-exclusive O_DIRECT writes from multiple threads */
-#define FMODE_DIO_PARALLEL_WRITE	((__force fmode_t)0x1000000)
+/* FMODE_* bit 24 */
 
 /* File is embedded in backing_file object */
-#define FMODE_BACKING		((__force fmode_t)0x2000000)
+#define FMODE_BACKING		((__force fmode_t)(1 << 25))
 
 /* File was opened by fanotify and shouldn't generate fanotify events */
-#define FMODE_NONOTIFY		((__force fmode_t)0x4000000)
+#define FMODE_NONOTIFY		((__force fmode_t)(1 << 26))
 
 /* File is capable of returning -EAGAIN if I/O will block */
-#define FMODE_NOWAIT		((__force fmode_t)0x8000000)
+#define FMODE_NOWAIT		((__force fmode_t)(1 << 27))
 
 /* File represents mount that needs unmounting */
-#define FMODE_NEED_UNMOUNT	((__force fmode_t)0x10000000)
+#define FMODE_NEED_UNMOUNT	((__force fmode_t)(1 << 28))
 
 /* File does not contribute to nr_files count */
-#define FMODE_NOACCOUNT		((__force fmode_t)0x20000000)
-
-/* File supports async buffered reads */
-#define FMODE_BUF_RASYNC	((__force fmode_t)0x40000000)
-
-/* File supports async nowait buffered writes */
-#define FMODE_BUF_WASYNC	((__force fmode_t)0x80000000)
+#define FMODE_NOACCOUNT		((__force fmode_t)(1 << 29))
 
 /*
  * Attribute flags.  These should be or-ed together to figure out what
@@ -1035,12 +1031,13 @@ struct file_handle {
 	__u32 handle_bytes;
 	int handle_type;
 	/* file identifier */
-	unsigned char f_handle[];
+	unsigned char f_handle[] __counted_by(handle_bytes);
 };
 
 static inline struct file *get_file(struct file *f)
 {
-	atomic_long_inc(&f->f_count);
+	long prior = atomic_long_fetch_inc_relaxed(&f->f_count);
+	WARN_ONCE(!prior, "struct file::f_count incremented from zero; use-after-free condition present!\n");
 	return f;
 }
 
@@ -2003,8 +2000,11 @@ struct iov_iter;
 struct io_uring_cmd;
 struct offset_ctx;
 
+typedef unsigned int __bitwise fop_flags_t;
+
 struct file_operations {
 	struct module *owner;
+	fop_flags_t fop_flags;
 	loff_t (*llseek) (struct file *, loff_t, int);
 	ssize_t (*read) (struct file *, char __user *, size_t, loff_t *);
 	ssize_t (*write) (struct file *, const char __user *, size_t, loff_t *);
@@ -2017,7 +2017,6 @@ struct file_operations {
 	long (*unlocked_ioctl) (struct file *, unsigned int, unsigned long);
 	long (*compat_ioctl) (struct file *, unsigned int, unsigned long);
 	int (*mmap) (struct file *, struct vm_area_struct *);
-	unsigned long mmap_supported_flags;
 	int (*open) (struct inode *, struct file *);
 	int (*flush) (struct file *, fl_owner_t id);
 	int (*release) (struct inode *, struct file *);
@@ -2048,6 +2047,17 @@ struct file_operations {
 				unsigned int poll_flags);
 } __randomize_layout;
 
+/* Supports async buffered reads */
+#define FOP_BUFFER_RASYNC	((__force fop_flags_t)(1 << 0))
+/* Supports async buffered writes */
+#define FOP_BUFFER_WASYNC	((__force fop_flags_t)(1 << 1))
+/* Supports synchronous page faults for mappings */
+#define FOP_MMAP_SYNC		((__force fop_flags_t)(1 << 2))
+/* Supports non-exclusive O_DIRECT writes from multiple threads */
+#define FOP_DIO_PARALLEL_WRITE	((__force fop_flags_t)(1 << 3))
+/* Contains huge pages */
+#define FOP_HUGE_PAGES		((__force fop_flags_t)(1 << 4))
+
 /* Wrap a directory iterator that needs exclusive inode access */
 int wrap_directory_iterator(struct file *, struct dir_context *,
 			    int (*) (struct file *, struct dir_context *));
@@ -2253,7 +2263,13 @@ static inline bool sb_rdonly(const struct super_block *sb) { return sb->s_flags
 
 #define IS_DEADDIR(inode)	((inode)->i_flags & S_DEAD)
 #define IS_NOCMTIME(inode)	((inode)->i_flags & S_NOCMTIME)
+
+#ifdef CONFIG_SWAP
 #define IS_SWAPFILE(inode)	((inode)->i_flags & S_SWAPFILE)
+#else
+#define IS_SWAPFILE(inode)	((void)(inode), 0U)
+#endif
+
 #define IS_PRIVATE(inode)	((inode)->i_flags & S_PRIVATE)
 #define IS_IMA(inode)		((inode)->i_flags & S_IMA)
 #define IS_AUTOMOUNT(inode)	((inode)->i_flags & S_AUTOMOUNT)
@@ -3340,6 +3356,8 @@ void simple_offset_init(struct offset_ctx *octx);
 int simple_offset_add(struct offset_ctx *octx, struct dentry *dentry);
 void simple_offset_remove(struct offset_ctx *octx, struct dentry *dentry);
 int simple_offset_empty(struct dentry *dentry);
+int simple_offset_rename(struct inode *old_dir, struct dentry *old_dentry,
+			 struct inode *new_dir, struct dentry *new_dentry);
 int simple_offset_rename_exchange(struct inode *old_dir,
 				  struct dentry *old_dentry,
 				  struct inode *new_dir,
diff --git a/include/linux/fs_parser.h b/include/linux/fs_parser.h
index 01542c4b87a2..d3350979115f 100644
--- a/include/linux/fs_parser.h
+++ b/include/linux/fs_parser.h
@@ -132,4 +132,8 @@ static inline bool fs_validate_description(const char *name,
 #define fsparam_path(NAME, OPT)	__fsparam(fs_param_is_path, NAME, OPT, 0, NULL)
 #define fsparam_fd(NAME, OPT)	__fsparam(fs_param_is_fd, NAME, OPT, 0, NULL)
 
+/* String parameter that allows empty argument */
+#define fsparam_string_empty(NAME, OPT) \
+	__fsparam(fs_param_is_string, NAME, OPT, fs_param_can_be_empty, NULL)
+
 #endif /* _LINUX_FS_PARSER_H */
diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h
index 77b30a8c6076..b06f7c426d38 100644
--- a/include/linux/hugetlb.h
+++ b/include/linux/hugetlb.h
@@ -554,17 +554,13 @@ static inline struct hugetlbfs_inode_info *HUGETLBFS_I(struct inode *inode)
 	return container_of(inode, struct hugetlbfs_inode_info, vfs_inode);
 }
 
-extern const struct file_operations hugetlbfs_file_operations;
 extern const struct vm_operations_struct hugetlb_vm_ops;
 struct file *hugetlb_file_setup(const char *name, size_t size, vm_flags_t acct,
 				int creat_flags, int page_size_log);
 
-static inline bool is_file_hugepages(struct file *file)
+static inline bool is_file_hugepages(const struct file *file)
 {
-	if (file->f_op == &hugetlbfs_file_operations)
-		return true;
-
-	return is_file_shm_hugepages(file);
+	return file->f_op->fop_flags & FOP_HUGE_PAGES;
 }
 
 static inline struct hstate *hstate_inode(struct inode *i)
diff --git a/include/linux/namei.h b/include/linux/namei.h
index 74e0cc14ebf8..967aa9ea9f96 100644
--- a/include/linux/namei.h
+++ b/include/linux/namei.h
@@ -44,6 +44,7 @@ enum {LAST_NORM, LAST_ROOT, LAST_DOT, LAST_DOTDOT};
 #define LOOKUP_BENEATH		0x080000 /* No escaping from starting point. */
 #define LOOKUP_IN_ROOT		0x100000 /* Treat dirfd as fs root. */
 #define LOOKUP_CACHED		0x200000 /* Only do cached lookup */
+#define LOOKUP_LINKAT_EMPTY	0x400000 /* Linkat request with empty path. */
 /* LOOKUP_* flags which do scope-related checks based on the dirfd. */
 #define LOOKUP_IS_SCOPED (LOOKUP_BENEATH | LOOKUP_IN_ROOT)
 
diff --git a/include/linux/seq_file.h b/include/linux/seq_file.h
index 234bcdb1fba4..8bd4fda6e027 100644
--- a/include/linux/seq_file.h
+++ b/include/linux/seq_file.h
@@ -118,7 +118,18 @@ void seq_vprintf(struct seq_file *m, const char *fmt, va_list args);
 __printf(2, 3)
 void seq_printf(struct seq_file *m, const char *fmt, ...);
 void seq_putc(struct seq_file *m, char c);
-void seq_puts(struct seq_file *m, const char *s);
+void __seq_puts(struct seq_file *m, const char *s);
+
+static __always_inline void seq_puts(struct seq_file *m, const char *s)
+{
+	if (!__builtin_constant_p(*s))
+		__seq_puts(m, s);
+	else if (s[0] && !s[1])
+		seq_putc(m, s[0]);
+	else
+		seq_write(m, s, __builtin_strlen(s));
+}
+
 void seq_put_decimal_ull_width(struct seq_file *m, const char *delimiter,
 			       unsigned long long num, unsigned int width);
 void seq_put_decimal_ull(struct seq_file *m, const char *delimiter,
diff --git a/include/linux/shm.h b/include/linux/shm.h
index c55bef0538e5..1d3d3ae958fb 100644
--- a/include/linux/shm.h
+++ b/include/linux/shm.h
@@ -16,7 +16,6 @@ struct sysv_shm {
 
 long do_shmat(int shmid, char __user *shmaddr, int shmflg, unsigned long *addr,
 	      unsigned long shmlba);
-bool is_file_shm_hugepages(struct file *file);
 void exit_shm(struct task_struct *task);
 #define shm_init_task(task) INIT_LIST_HEAD(&(task)->sysvshm.shm_clist)
 #else
@@ -30,10 +29,6 @@ static inline long do_shmat(int shmid, char __user *shmaddr,
 {
 	return -ENOSYS;
 }
-static inline bool is_file_shm_hugepages(struct file *file)
-{
-	return false;
-}
 static inline void exit_shm(struct task_struct *task)
 {
 }
diff --git a/include/linux/stat.h b/include/linux/stat.h
index 52150570d37a..bf92441dbad2 100644
--- a/include/linux/stat.h
+++ b/include/linux/stat.h
@@ -53,6 +53,7 @@ struct kstat {
 	u32		dio_mem_align;
 	u32		dio_offset_align;
 	u64		change_cookie;
+	u64		subvol;
 };
 
 /* These definitions are internal to the kernel for now. Mainly used by nfsd. */