linux-stable/fs/stat.c
Linus Torvalds 35b51afd23 RISC-V Patches for the 5.19 Merge Window, Part 1
* Support for the Svpbmt extension, which allows memory attributes to be
   encoded in pages.
 * Support for the Allwinner D1's implementation of page-based memory
   attributes.
 * Support for running rv32 binaries on rv64 systems, via the compat
   subsystem.
 * Support for kexec_file().
 * Support for the new generic ticket-based spinlocks, which allows us to
   also move to qrwlock.  These should have already gone in through the
   asm-geneic tree as well.
 * A handful of cleanups and fixes, include some larger ones around
   atomics and XIP.
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Merge tag 'riscv-for-linus-5.19-mw0' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux

Pull RISC-V updates from Palmer Dabbelt:

 - Support for the Svpbmt extension, which allows memory attributes to
   be encoded in pages

 - Support for the Allwinner D1's implementation of page-based memory
   attributes

 - Support for running rv32 binaries on rv64 systems, via the compat
   subsystem

 - Support for kexec_file()

 - Support for the new generic ticket-based spinlocks, which allows us
   to also move to qrwlock. These should have already gone in through
   the asm-geneic tree as well

 - A handful of cleanups and fixes, include some larger ones around
   atomics and XIP

* tag 'riscv-for-linus-5.19-mw0' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: (51 commits)
  RISC-V: Prepare dropping week attribute from arch_kexec_apply_relocations[_add]
  riscv: compat: Using seperated vdso_maps for compat_vdso_info
  RISC-V: Fix the XIP build
  RISC-V: Split out the XIP fixups into their own file
  RISC-V: ignore xipImage
  RISC-V: Avoid empty create_*_mapping definitions
  riscv: Don't output a bogus mmu-type on a no MMU kernel
  riscv: atomic: Add custom conditional atomic operation implementation
  riscv: atomic: Optimize dec_if_positive functions
  riscv: atomic: Cleanup unnecessary definition
  RISC-V: Load purgatory in kexec_file
  RISC-V: Add purgatory
  RISC-V: Support for kexec_file on panic
  RISC-V: Add kexec_file support
  RISC-V: use memcpy for kexec_file mode
  kexec_file: Fix kexec_file.c build error for riscv platform
  riscv: compat: Add COMPAT Kbuild skeletal support
  riscv: compat: ptrace: Add compat_arch_ptrace implement
  riscv: compat: signal: Add rt_frame implementation
  riscv: add memory-type errata for T-Head
  ...
2022-05-31 14:10:54 -07:00

813 lines
22 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* linux/fs/stat.c
*
* Copyright (C) 1991, 1992 Linus Torvalds
*/
#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;
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;
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);