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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /fs/stat.c
parentInitial commit. (diff)
downloadlinux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz
linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'fs/stat.c')
-rw-r--r--fs/stat.c827
1 files changed, 827 insertions, 0 deletions
diff --git a/fs/stat.c b/fs/stat.c
new file mode 100644
index 000000000..ef50573c7
--- /dev/null
+++ b/fs/stat.c
@@ -0,0 +1,827 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * linux/fs/stat.c
+ *
+ * Copyright (C) 1991, 1992 Linus Torvalds
+ */
+
+#include <linux/blkdev.h>
+#include <linux/export.h>
+#include <linux/mm.h>
+#include <linux/errno.h>
+#include <linux/file.h>
+#include <linux/highuid.h>
+#include <linux/fs.h>
+#include <linux/namei.h>
+#include <linux/security.h>
+#include <linux/cred.h>
+#include <linux/syscalls.h>
+#include <linux/pagemap.h>
+#include <linux/compat.h>
+
+#include <linux/uaccess.h>
+#include <asm/unistd.h>
+
+#include "internal.h"
+#include "mount.h"
+
+/**
+ * generic_fillattr - Fill in the basic attributes from the inode struct
+ * @mnt_userns: user namespace of the mount the inode was found from
+ * @inode: Inode to use as the source
+ * @stat: Where to fill in the attributes
+ *
+ * Fill in the basic attributes in the kstat structure from data that's to be
+ * found on the VFS inode structure. This is the default if no getattr inode
+ * operation is supplied.
+ *
+ * If the inode has been found through an idmapped mount the user namespace of
+ * the vfsmount must be passed through @mnt_userns. This function will then
+ * take care to map the inode according to @mnt_userns before filling in the
+ * uid and gid filds. On non-idmapped mounts or if permission checking is to be
+ * performed on the raw inode simply passs init_user_ns.
+ */
+void generic_fillattr(struct user_namespace *mnt_userns, struct inode *inode,
+ struct kstat *stat)
+{
+ stat->dev = inode->i_sb->s_dev;
+ stat->ino = inode->i_ino;
+ stat->mode = inode->i_mode;
+ stat->nlink = inode->i_nlink;
+ stat->uid = i_uid_into_mnt(mnt_userns, inode);
+ stat->gid = i_gid_into_mnt(mnt_userns, inode);
+ stat->rdev = inode->i_rdev;
+ stat->size = i_size_read(inode);
+ stat->atime = inode->i_atime;
+ stat->mtime = inode->i_mtime;
+ stat->ctime = inode->i_ctime;
+ stat->blksize = i_blocksize(inode);
+ stat->blocks = inode->i_blocks;
+}
+EXPORT_SYMBOL(generic_fillattr);
+
+/**
+ * generic_fill_statx_attr - Fill in the statx attributes from the inode flags
+ * @inode: Inode to use as the source
+ * @stat: Where to fill in the attribute flags
+ *
+ * Fill in the STATX_ATTR_* flags in the kstat structure for properties of the
+ * inode that are published on i_flags and enforced by the VFS.
+ */
+void generic_fill_statx_attr(struct inode *inode, struct kstat *stat)
+{
+ if (inode->i_flags & S_IMMUTABLE)
+ stat->attributes |= STATX_ATTR_IMMUTABLE;
+ if (inode->i_flags & S_APPEND)
+ stat->attributes |= STATX_ATTR_APPEND;
+ stat->attributes_mask |= KSTAT_ATTR_VFS_FLAGS;
+}
+EXPORT_SYMBOL(generic_fill_statx_attr);
+
+/**
+ * vfs_getattr_nosec - getattr without security checks
+ * @path: file to get attributes from
+ * @stat: structure to return attributes in
+ * @request_mask: STATX_xxx flags indicating what the caller wants
+ * @query_flags: Query mode (AT_STATX_SYNC_TYPE)
+ *
+ * Get attributes without calling security_inode_getattr.
+ *
+ * Currently the only caller other than vfs_getattr is internal to the
+ * filehandle lookup code, which uses only the inode number and returns no
+ * attributes to any user. Any other code probably wants vfs_getattr.
+ */
+int vfs_getattr_nosec(const struct path *path, struct kstat *stat,
+ u32 request_mask, unsigned int query_flags)
+{
+ struct user_namespace *mnt_userns;
+ struct inode *inode = d_backing_inode(path->dentry);
+
+ memset(stat, 0, sizeof(*stat));
+ stat->result_mask |= STATX_BASIC_STATS;
+ query_flags &= AT_STATX_SYNC_TYPE;
+
+ /* allow the fs to override these if it really wants to */
+ /* SB_NOATIME means filesystem supplies dummy atime value */
+ if (inode->i_sb->s_flags & SB_NOATIME)
+ stat->result_mask &= ~STATX_ATIME;
+
+ /*
+ * Note: If you add another clause to set an attribute flag, please
+ * update attributes_mask below.
+ */
+ if (IS_AUTOMOUNT(inode))
+ stat->attributes |= STATX_ATTR_AUTOMOUNT;
+
+ if (IS_DAX(inode))
+ stat->attributes |= STATX_ATTR_DAX;
+
+ stat->attributes_mask |= (STATX_ATTR_AUTOMOUNT |
+ STATX_ATTR_DAX);
+
+ mnt_userns = mnt_user_ns(path->mnt);
+ if (inode->i_op->getattr)
+ return inode->i_op->getattr(mnt_userns, path, stat,
+ request_mask, query_flags);
+
+ generic_fillattr(mnt_userns, inode, stat);
+ return 0;
+}
+EXPORT_SYMBOL(vfs_getattr_nosec);
+
+/*
+ * vfs_getattr - Get the enhanced basic attributes of a file
+ * @path: The file of interest
+ * @stat: Where to return the statistics
+ * @request_mask: STATX_xxx flags indicating what the caller wants
+ * @query_flags: Query mode (AT_STATX_SYNC_TYPE)
+ *
+ * Ask the filesystem for a file's attributes. The caller must indicate in
+ * request_mask and query_flags to indicate what they want.
+ *
+ * If the file is remote, the filesystem can be forced to update the attributes
+ * from the backing store by passing AT_STATX_FORCE_SYNC in query_flags or can
+ * suppress the update by passing AT_STATX_DONT_SYNC.
+ *
+ * Bits must have been set in request_mask to indicate which attributes the
+ * caller wants retrieving. Any such attribute not requested may be returned
+ * anyway, but the value may be approximate, and, if remote, may not have been
+ * synchronised with the server.
+ *
+ * 0 will be returned on success, and a -ve error code if unsuccessful.
+ */
+int vfs_getattr(const struct path *path, struct kstat *stat,
+ u32 request_mask, unsigned int query_flags)
+{
+ int retval;
+
+ retval = security_inode_getattr(path);
+ if (retval)
+ return retval;
+ return vfs_getattr_nosec(path, stat, request_mask, query_flags);
+}
+EXPORT_SYMBOL(vfs_getattr);
+
+/**
+ * vfs_fstat - Get the basic attributes by file descriptor
+ * @fd: The file descriptor referring to the file of interest
+ * @stat: The result structure to fill in.
+ *
+ * This function is a wrapper around vfs_getattr(). The main difference is
+ * that it uses a file descriptor to determine the file location.
+ *
+ * 0 will be returned on success, and a -ve error code if unsuccessful.
+ */
+int vfs_fstat(int fd, struct kstat *stat)
+{
+ struct fd f;
+ int error;
+
+ f = fdget_raw(fd);
+ if (!f.file)
+ return -EBADF;
+ error = vfs_getattr(&f.file->f_path, stat, STATX_BASIC_STATS, 0);
+ fdput(f);
+ return error;
+}
+
+int getname_statx_lookup_flags(int flags)
+{
+ int lookup_flags = 0;
+
+ if (!(flags & AT_SYMLINK_NOFOLLOW))
+ lookup_flags |= LOOKUP_FOLLOW;
+ if (!(flags & AT_NO_AUTOMOUNT))
+ lookup_flags |= LOOKUP_AUTOMOUNT;
+ if (flags & AT_EMPTY_PATH)
+ lookup_flags |= LOOKUP_EMPTY;
+
+ return lookup_flags;
+}
+
+/**
+ * vfs_statx - Get basic and extra attributes by filename
+ * @dfd: A file descriptor representing the base dir for a relative filename
+ * @filename: The name of the file of interest
+ * @flags: Flags to control the query
+ * @stat: The result structure to fill in.
+ * @request_mask: STATX_xxx flags indicating what the caller wants
+ *
+ * This function is a wrapper around vfs_getattr(). The main difference is
+ * that it uses a filename and base directory to determine the file location.
+ * Additionally, the use of AT_SYMLINK_NOFOLLOW in flags will prevent a symlink
+ * at the given name from being referenced.
+ *
+ * 0 will be returned on success, and a -ve error code if unsuccessful.
+ */
+static int vfs_statx(int dfd, struct filename *filename, int flags,
+ struct kstat *stat, u32 request_mask)
+{
+ struct path path;
+ unsigned int lookup_flags = getname_statx_lookup_flags(flags);
+ int error;
+
+ if (flags & ~(AT_SYMLINK_NOFOLLOW | AT_NO_AUTOMOUNT | AT_EMPTY_PATH |
+ AT_STATX_SYNC_TYPE))
+ return -EINVAL;
+
+retry:
+ error = filename_lookup(dfd, filename, lookup_flags, &path, NULL);
+ if (error)
+ goto out;
+
+ error = vfs_getattr(&path, stat, request_mask, flags);
+
+ stat->mnt_id = real_mount(path.mnt)->mnt_id;
+ stat->result_mask |= STATX_MNT_ID;
+
+ if (path.mnt->mnt_root == path.dentry)
+ stat->attributes |= STATX_ATTR_MOUNT_ROOT;
+ stat->attributes_mask |= STATX_ATTR_MOUNT_ROOT;
+
+ /* Handle STATX_DIOALIGN for block devices. */
+ if (request_mask & STATX_DIOALIGN) {
+ struct inode *inode = d_backing_inode(path.dentry);
+
+ if (S_ISBLK(inode->i_mode))
+ bdev_statx_dioalign(inode, stat);
+ }
+
+ path_put(&path);
+ if (retry_estale(error, lookup_flags)) {
+ lookup_flags |= LOOKUP_REVAL;
+ goto retry;
+ }
+out:
+ return error;
+}
+
+int vfs_fstatat(int dfd, const char __user *filename,
+ struct kstat *stat, int flags)
+{
+ int ret;
+ int statx_flags = flags | AT_NO_AUTOMOUNT;
+ struct filename *name;
+
+ name = getname_flags(filename, getname_statx_lookup_flags(statx_flags), NULL);
+ ret = vfs_statx(dfd, name, statx_flags, stat, STATX_BASIC_STATS);
+ putname(name);
+
+ return ret;
+}
+
+#ifdef __ARCH_WANT_OLD_STAT
+
+/*
+ * For backward compatibility? Maybe this should be moved
+ * into arch/i386 instead?
+ */
+static int cp_old_stat(struct kstat *stat, struct __old_kernel_stat __user * statbuf)
+{
+ static int warncount = 5;
+ struct __old_kernel_stat tmp;
+
+ if (warncount > 0) {
+ warncount--;
+ printk(KERN_WARNING "VFS: Warning: %s using old stat() call. Recompile your binary.\n",
+ current->comm);
+ } else if (warncount < 0) {
+ /* it's laughable, but... */
+ warncount = 0;
+ }
+
+ memset(&tmp, 0, sizeof(struct __old_kernel_stat));
+ tmp.st_dev = old_encode_dev(stat->dev);
+ tmp.st_ino = stat->ino;
+ if (sizeof(tmp.st_ino) < sizeof(stat->ino) && tmp.st_ino != stat->ino)
+ return -EOVERFLOW;
+ tmp.st_mode = stat->mode;
+ tmp.st_nlink = stat->nlink;
+ if (tmp.st_nlink != stat->nlink)
+ return -EOVERFLOW;
+ SET_UID(tmp.st_uid, from_kuid_munged(current_user_ns(), stat->uid));
+ SET_GID(tmp.st_gid, from_kgid_munged(current_user_ns(), stat->gid));
+ tmp.st_rdev = old_encode_dev(stat->rdev);
+#if BITS_PER_LONG == 32
+ if (stat->size > MAX_NON_LFS)
+ return -EOVERFLOW;
+#endif
+ tmp.st_size = stat->size;
+ tmp.st_atime = stat->atime.tv_sec;
+ tmp.st_mtime = stat->mtime.tv_sec;
+ tmp.st_ctime = stat->ctime.tv_sec;
+ return copy_to_user(statbuf,&tmp,sizeof(tmp)) ? -EFAULT : 0;
+}
+
+SYSCALL_DEFINE2(stat, const char __user *, filename,
+ struct __old_kernel_stat __user *, statbuf)
+{
+ struct kstat stat;
+ int error;
+
+ error = vfs_stat(filename, &stat);
+ if (error)
+ return error;
+
+ return cp_old_stat(&stat, statbuf);
+}
+
+SYSCALL_DEFINE2(lstat, const char __user *, filename,
+ struct __old_kernel_stat __user *, statbuf)
+{
+ struct kstat stat;
+ int error;
+
+ error = vfs_lstat(filename, &stat);
+ if (error)
+ return error;
+
+ return cp_old_stat(&stat, statbuf);
+}
+
+SYSCALL_DEFINE2(fstat, unsigned int, fd, struct __old_kernel_stat __user *, statbuf)
+{
+ struct kstat stat;
+ int error = vfs_fstat(fd, &stat);
+
+ if (!error)
+ error = cp_old_stat(&stat, statbuf);
+
+ return error;
+}
+
+#endif /* __ARCH_WANT_OLD_STAT */
+
+#ifdef __ARCH_WANT_NEW_STAT
+
+#if BITS_PER_LONG == 32
+# define choose_32_64(a,b) a
+#else
+# define choose_32_64(a,b) b
+#endif
+
+#ifndef INIT_STRUCT_STAT_PADDING
+# define INIT_STRUCT_STAT_PADDING(st) memset(&st, 0, sizeof(st))
+#endif
+
+static int cp_new_stat(struct kstat *stat, struct stat __user *statbuf)
+{
+ struct stat tmp;
+
+ if (sizeof(tmp.st_dev) < 4 && !old_valid_dev(stat->dev))
+ return -EOVERFLOW;
+ if (sizeof(tmp.st_rdev) < 4 && !old_valid_dev(stat->rdev))
+ return -EOVERFLOW;
+#if BITS_PER_LONG == 32
+ if (stat->size > MAX_NON_LFS)
+ return -EOVERFLOW;
+#endif
+
+ INIT_STRUCT_STAT_PADDING(tmp);
+ tmp.st_dev = new_encode_dev(stat->dev);
+ tmp.st_ino = stat->ino;
+ if (sizeof(tmp.st_ino) < sizeof(stat->ino) && tmp.st_ino != stat->ino)
+ return -EOVERFLOW;
+ tmp.st_mode = stat->mode;
+ tmp.st_nlink = stat->nlink;
+ if (tmp.st_nlink != stat->nlink)
+ return -EOVERFLOW;
+ SET_UID(tmp.st_uid, from_kuid_munged(current_user_ns(), stat->uid));
+ SET_GID(tmp.st_gid, from_kgid_munged(current_user_ns(), stat->gid));
+ tmp.st_rdev = new_encode_dev(stat->rdev);
+ tmp.st_size = stat->size;
+ tmp.st_atime = stat->atime.tv_sec;
+ tmp.st_mtime = stat->mtime.tv_sec;
+ tmp.st_ctime = stat->ctime.tv_sec;
+#ifdef STAT_HAVE_NSEC
+ tmp.st_atime_nsec = stat->atime.tv_nsec;
+ tmp.st_mtime_nsec = stat->mtime.tv_nsec;
+ tmp.st_ctime_nsec = stat->ctime.tv_nsec;
+#endif
+ tmp.st_blocks = stat->blocks;
+ tmp.st_blksize = stat->blksize;
+ return copy_to_user(statbuf,&tmp,sizeof(tmp)) ? -EFAULT : 0;
+}
+
+SYSCALL_DEFINE2(newstat, const char __user *, filename,
+ struct stat __user *, statbuf)
+{
+ struct kstat stat;
+ int error = vfs_stat(filename, &stat);
+
+ if (error)
+ return error;
+ return cp_new_stat(&stat, statbuf);
+}
+
+SYSCALL_DEFINE2(newlstat, const char __user *, filename,
+ struct stat __user *, statbuf)
+{
+ struct kstat stat;
+ int error;
+
+ error = vfs_lstat(filename, &stat);
+ if (error)
+ return error;
+
+ return cp_new_stat(&stat, statbuf);
+}
+
+#if !defined(__ARCH_WANT_STAT64) || defined(__ARCH_WANT_SYS_NEWFSTATAT)
+SYSCALL_DEFINE4(newfstatat, int, dfd, const char __user *, filename,
+ struct stat __user *, statbuf, int, flag)
+{
+ struct kstat stat;
+ int error;
+
+ error = vfs_fstatat(dfd, filename, &stat, flag);
+ if (error)
+ return error;
+ return cp_new_stat(&stat, statbuf);
+}
+#endif
+
+SYSCALL_DEFINE2(newfstat, unsigned int, fd, struct stat __user *, statbuf)
+{
+ struct kstat stat;
+ int error = vfs_fstat(fd, &stat);
+
+ if (!error)
+ error = cp_new_stat(&stat, statbuf);
+
+ return error;
+}
+#endif
+
+static int do_readlinkat(int dfd, const char __user *pathname,
+ char __user *buf, int bufsiz)
+{
+ struct path path;
+ int error;
+ int empty = 0;
+ unsigned int lookup_flags = LOOKUP_EMPTY;
+
+ if (bufsiz <= 0)
+ return -EINVAL;
+
+retry:
+ error = user_path_at_empty(dfd, pathname, lookup_flags, &path, &empty);
+ if (!error) {
+ struct inode *inode = d_backing_inode(path.dentry);
+
+ error = empty ? -ENOENT : -EINVAL;
+ /*
+ * AFS mountpoints allow readlink(2) but are not symlinks
+ */
+ if (d_is_symlink(path.dentry) || inode->i_op->readlink) {
+ error = security_inode_readlink(path.dentry);
+ if (!error) {
+ touch_atime(&path);
+ error = vfs_readlink(path.dentry, buf, bufsiz);
+ }
+ }
+ path_put(&path);
+ if (retry_estale(error, lookup_flags)) {
+ lookup_flags |= LOOKUP_REVAL;
+ goto retry;
+ }
+ }
+ return error;
+}
+
+SYSCALL_DEFINE4(readlinkat, int, dfd, const char __user *, pathname,
+ char __user *, buf, int, bufsiz)
+{
+ return do_readlinkat(dfd, pathname, buf, bufsiz);
+}
+
+SYSCALL_DEFINE3(readlink, const char __user *, path, char __user *, buf,
+ int, bufsiz)
+{
+ return do_readlinkat(AT_FDCWD, path, buf, bufsiz);
+}
+
+
+/* ---------- LFS-64 ----------- */
+#if defined(__ARCH_WANT_STAT64) || defined(__ARCH_WANT_COMPAT_STAT64)
+
+#ifndef INIT_STRUCT_STAT64_PADDING
+# define INIT_STRUCT_STAT64_PADDING(st) memset(&st, 0, sizeof(st))
+#endif
+
+static long cp_new_stat64(struct kstat *stat, struct stat64 __user *statbuf)
+{
+ struct stat64 tmp;
+
+ INIT_STRUCT_STAT64_PADDING(tmp);
+#ifdef CONFIG_MIPS
+ /* mips has weird padding, so we don't get 64 bits there */
+ tmp.st_dev = new_encode_dev(stat->dev);
+ tmp.st_rdev = new_encode_dev(stat->rdev);
+#else
+ tmp.st_dev = huge_encode_dev(stat->dev);
+ tmp.st_rdev = huge_encode_dev(stat->rdev);
+#endif
+ tmp.st_ino = stat->ino;
+ if (sizeof(tmp.st_ino) < sizeof(stat->ino) && tmp.st_ino != stat->ino)
+ return -EOVERFLOW;
+#ifdef STAT64_HAS_BROKEN_ST_INO
+ tmp.__st_ino = stat->ino;
+#endif
+ tmp.st_mode = stat->mode;
+ tmp.st_nlink = stat->nlink;
+ tmp.st_uid = from_kuid_munged(current_user_ns(), stat->uid);
+ tmp.st_gid = from_kgid_munged(current_user_ns(), stat->gid);
+ tmp.st_atime = stat->atime.tv_sec;
+ tmp.st_atime_nsec = stat->atime.tv_nsec;
+ tmp.st_mtime = stat->mtime.tv_sec;
+ tmp.st_mtime_nsec = stat->mtime.tv_nsec;
+ tmp.st_ctime = stat->ctime.tv_sec;
+ tmp.st_ctime_nsec = stat->ctime.tv_nsec;
+ tmp.st_size = stat->size;
+ tmp.st_blocks = stat->blocks;
+ tmp.st_blksize = stat->blksize;
+ return copy_to_user(statbuf,&tmp,sizeof(tmp)) ? -EFAULT : 0;
+}
+
+SYSCALL_DEFINE2(stat64, const char __user *, filename,
+ struct stat64 __user *, statbuf)
+{
+ struct kstat stat;
+ int error = vfs_stat(filename, &stat);
+
+ if (!error)
+ error = cp_new_stat64(&stat, statbuf);
+
+ return error;
+}
+
+SYSCALL_DEFINE2(lstat64, const char __user *, filename,
+ struct stat64 __user *, statbuf)
+{
+ struct kstat stat;
+ int error = vfs_lstat(filename, &stat);
+
+ if (!error)
+ error = cp_new_stat64(&stat, statbuf);
+
+ return error;
+}
+
+SYSCALL_DEFINE2(fstat64, unsigned long, fd, struct stat64 __user *, statbuf)
+{
+ struct kstat stat;
+ int error = vfs_fstat(fd, &stat);
+
+ if (!error)
+ error = cp_new_stat64(&stat, statbuf);
+
+ return error;
+}
+
+SYSCALL_DEFINE4(fstatat64, int, dfd, const char __user *, filename,
+ struct stat64 __user *, statbuf, int, flag)
+{
+ struct kstat stat;
+ int error;
+
+ error = vfs_fstatat(dfd, filename, &stat, flag);
+ if (error)
+ return error;
+ return cp_new_stat64(&stat, statbuf);
+}
+#endif /* __ARCH_WANT_STAT64 || __ARCH_WANT_COMPAT_STAT64 */
+
+static noinline_for_stack int
+cp_statx(const struct kstat *stat, struct statx __user *buffer)
+{
+ struct statx tmp;
+
+ memset(&tmp, 0, sizeof(tmp));
+
+ tmp.stx_mask = stat->result_mask;
+ tmp.stx_blksize = stat->blksize;
+ tmp.stx_attributes = stat->attributes;
+ tmp.stx_nlink = stat->nlink;
+ tmp.stx_uid = from_kuid_munged(current_user_ns(), stat->uid);
+ tmp.stx_gid = from_kgid_munged(current_user_ns(), stat->gid);
+ tmp.stx_mode = stat->mode;
+ tmp.stx_ino = stat->ino;
+ tmp.stx_size = stat->size;
+ tmp.stx_blocks = stat->blocks;
+ tmp.stx_attributes_mask = stat->attributes_mask;
+ tmp.stx_atime.tv_sec = stat->atime.tv_sec;
+ tmp.stx_atime.tv_nsec = stat->atime.tv_nsec;
+ tmp.stx_btime.tv_sec = stat->btime.tv_sec;
+ tmp.stx_btime.tv_nsec = stat->btime.tv_nsec;
+ tmp.stx_ctime.tv_sec = stat->ctime.tv_sec;
+ tmp.stx_ctime.tv_nsec = stat->ctime.tv_nsec;
+ tmp.stx_mtime.tv_sec = stat->mtime.tv_sec;
+ tmp.stx_mtime.tv_nsec = stat->mtime.tv_nsec;
+ tmp.stx_rdev_major = MAJOR(stat->rdev);
+ tmp.stx_rdev_minor = MINOR(stat->rdev);
+ tmp.stx_dev_major = MAJOR(stat->dev);
+ tmp.stx_dev_minor = MINOR(stat->dev);
+ tmp.stx_mnt_id = stat->mnt_id;
+ tmp.stx_dio_mem_align = stat->dio_mem_align;
+ tmp.stx_dio_offset_align = stat->dio_offset_align;
+
+ return copy_to_user(buffer, &tmp, sizeof(tmp)) ? -EFAULT : 0;
+}
+
+int do_statx(int dfd, struct filename *filename, unsigned int flags,
+ unsigned int mask, struct statx __user *buffer)
+{
+ struct kstat stat;
+ int error;
+
+ if (mask & STATX__RESERVED)
+ return -EINVAL;
+ if ((flags & AT_STATX_SYNC_TYPE) == AT_STATX_SYNC_TYPE)
+ return -EINVAL;
+
+ error = vfs_statx(dfd, filename, flags, &stat, mask);
+ if (error)
+ return error;
+
+ return cp_statx(&stat, buffer);
+}
+
+/**
+ * sys_statx - System call to get enhanced stats
+ * @dfd: Base directory to pathwalk from *or* fd to stat.
+ * @filename: File to stat or "" with AT_EMPTY_PATH
+ * @flags: AT_* flags to control pathwalk.
+ * @mask: Parts of statx struct actually required.
+ * @buffer: Result buffer.
+ *
+ * Note that fstat() can be emulated by setting dfd to the fd of interest,
+ * supplying "" as the filename and setting AT_EMPTY_PATH in the flags.
+ */
+SYSCALL_DEFINE5(statx,
+ int, dfd, const char __user *, filename, unsigned, flags,
+ unsigned int, mask,
+ struct statx __user *, buffer)
+{
+ int ret;
+ struct filename *name;
+
+ name = getname_flags(filename, getname_statx_lookup_flags(flags), NULL);
+ ret = do_statx(dfd, name, flags, mask, buffer);
+ putname(name);
+
+ return ret;
+}
+
+#if defined(CONFIG_COMPAT) && defined(__ARCH_WANT_COMPAT_STAT)
+static int cp_compat_stat(struct kstat *stat, struct compat_stat __user *ubuf)
+{
+ struct compat_stat tmp;
+
+ if (sizeof(tmp.st_dev) < 4 && !old_valid_dev(stat->dev))
+ return -EOVERFLOW;
+ if (sizeof(tmp.st_rdev) < 4 && !old_valid_dev(stat->rdev))
+ return -EOVERFLOW;
+
+ memset(&tmp, 0, sizeof(tmp));
+ tmp.st_dev = new_encode_dev(stat->dev);
+ tmp.st_ino = stat->ino;
+ if (sizeof(tmp.st_ino) < sizeof(stat->ino) && tmp.st_ino != stat->ino)
+ return -EOVERFLOW;
+ tmp.st_mode = stat->mode;
+ tmp.st_nlink = stat->nlink;
+ if (tmp.st_nlink != stat->nlink)
+ return -EOVERFLOW;
+ SET_UID(tmp.st_uid, from_kuid_munged(current_user_ns(), stat->uid));
+ SET_GID(tmp.st_gid, from_kgid_munged(current_user_ns(), stat->gid));
+ tmp.st_rdev = new_encode_dev(stat->rdev);
+ if ((u64) stat->size > MAX_NON_LFS)
+ return -EOVERFLOW;
+ tmp.st_size = stat->size;
+ tmp.st_atime = stat->atime.tv_sec;
+ tmp.st_atime_nsec = stat->atime.tv_nsec;
+ tmp.st_mtime = stat->mtime.tv_sec;
+ tmp.st_mtime_nsec = stat->mtime.tv_nsec;
+ tmp.st_ctime = stat->ctime.tv_sec;
+ tmp.st_ctime_nsec = stat->ctime.tv_nsec;
+ tmp.st_blocks = stat->blocks;
+ tmp.st_blksize = stat->blksize;
+ return copy_to_user(ubuf, &tmp, sizeof(tmp)) ? -EFAULT : 0;
+}
+
+COMPAT_SYSCALL_DEFINE2(newstat, const char __user *, filename,
+ struct compat_stat __user *, statbuf)
+{
+ struct kstat stat;
+ int error;
+
+ error = vfs_stat(filename, &stat);
+ if (error)
+ return error;
+ return cp_compat_stat(&stat, statbuf);
+}
+
+COMPAT_SYSCALL_DEFINE2(newlstat, const char __user *, filename,
+ struct compat_stat __user *, statbuf)
+{
+ struct kstat stat;
+ int error;
+
+ error = vfs_lstat(filename, &stat);
+ if (error)
+ return error;
+ return cp_compat_stat(&stat, statbuf);
+}
+
+#ifndef __ARCH_WANT_STAT64
+COMPAT_SYSCALL_DEFINE4(newfstatat, unsigned int, dfd,
+ const char __user *, filename,
+ struct compat_stat __user *, statbuf, int, flag)
+{
+ struct kstat stat;
+ int error;
+
+ error = vfs_fstatat(dfd, filename, &stat, flag);
+ if (error)
+ return error;
+ return cp_compat_stat(&stat, statbuf);
+}
+#endif
+
+COMPAT_SYSCALL_DEFINE2(newfstat, unsigned int, fd,
+ struct compat_stat __user *, statbuf)
+{
+ struct kstat stat;
+ int error = vfs_fstat(fd, &stat);
+
+ if (!error)
+ error = cp_compat_stat(&stat, statbuf);
+ return error;
+}
+#endif
+
+/* Caller is here responsible for sufficient locking (ie. inode->i_lock) */
+void __inode_add_bytes(struct inode *inode, loff_t bytes)
+{
+ inode->i_blocks += bytes >> 9;
+ bytes &= 511;
+ inode->i_bytes += bytes;
+ if (inode->i_bytes >= 512) {
+ inode->i_blocks++;
+ inode->i_bytes -= 512;
+ }
+}
+EXPORT_SYMBOL(__inode_add_bytes);
+
+void inode_add_bytes(struct inode *inode, loff_t bytes)
+{
+ spin_lock(&inode->i_lock);
+ __inode_add_bytes(inode, bytes);
+ spin_unlock(&inode->i_lock);
+}
+
+EXPORT_SYMBOL(inode_add_bytes);
+
+void __inode_sub_bytes(struct inode *inode, loff_t bytes)
+{
+ inode->i_blocks -= bytes >> 9;
+ bytes &= 511;
+ if (inode->i_bytes < bytes) {
+ inode->i_blocks--;
+ inode->i_bytes += 512;
+ }
+ inode->i_bytes -= bytes;
+}
+
+EXPORT_SYMBOL(__inode_sub_bytes);
+
+void inode_sub_bytes(struct inode *inode, loff_t bytes)
+{
+ spin_lock(&inode->i_lock);
+ __inode_sub_bytes(inode, bytes);
+ spin_unlock(&inode->i_lock);
+}
+
+EXPORT_SYMBOL(inode_sub_bytes);
+
+loff_t inode_get_bytes(struct inode *inode)
+{
+ loff_t ret;
+
+ spin_lock(&inode->i_lock);
+ ret = __inode_get_bytes(inode);
+ spin_unlock(&inode->i_lock);
+ return ret;
+}
+
+EXPORT_SYMBOL(inode_get_bytes);
+
+void inode_set_bytes(struct inode *inode, loff_t bytes)
+{
+ /* Caller is here responsible for sufficient locking
+ * (ie. inode->i_lock) */
+ inode->i_blocks = bytes >> 9;
+ inode->i_bytes = bytes & 511;
+}
+
+EXPORT_SYMBOL(inode_set_bytes);