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-rw-r--r--fs/stat.c214
1 files changed, 176 insertions, 38 deletions
diff --git a/fs/stat.c b/fs/stat.c
index 3f14d1ef0868..a3804feadade 100644
--- a/fs/stat.c
+++ b/fs/stat.c
@@ -18,6 +18,15 @@
#include <linux/uaccess.h>
#include <asm/unistd.h>
+/**
+ * generic_fillattr - Fill in the basic attributes from the inode struct
+ * @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.
+ */
void generic_fillattr(struct inode *inode, struct kstat *stat)
{
stat->dev = inode->i_sb->s_dev;
@@ -33,81 +42,147 @@ void generic_fillattr(struct inode *inode, struct kstat *stat)
stat->ctime = inode->i_ctime;
stat->blksize = i_blocksize(inode);
stat->blocks = inode->i_blocks;
-}
+ if (IS_NOATIME(inode))
+ stat->result_mask &= ~STATX_ATIME;
+ if (IS_AUTOMOUNT(inode))
+ stat->attributes |= STATX_ATTR_AUTOMOUNT;
+}
EXPORT_SYMBOL(generic_fillattr);
/**
* 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 (KSTAT_QUERY_FLAGS)
*
* 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.
+ * 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(struct path *path, struct kstat *stat)
+int vfs_getattr_nosec(const struct path *path, struct kstat *stat,
+ u32 request_mask, unsigned int query_flags)
{
struct inode *inode = d_backing_inode(path->dentry);
+ memset(stat, 0, sizeof(*stat));
+ stat->result_mask |= STATX_BASIC_STATS;
+ request_mask &= STATX_ALL;
+ query_flags &= KSTAT_QUERY_FLAGS;
if (inode->i_op->getattr)
- return inode->i_op->getattr(path->mnt, path->dentry, stat);
+ return inode->i_op->getattr(path, stat, request_mask,
+ query_flags);
generic_fillattr(inode, stat);
return 0;
}
-
EXPORT_SYMBOL(vfs_getattr_nosec);
-int vfs_getattr(struct path *path, struct kstat *stat)
+/*
+ * 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 (KSTAT_QUERY_FLAGS)
+ *
+ * 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);
+ return vfs_getattr_nosec(path, stat, request_mask, query_flags);
}
-
EXPORT_SYMBOL(vfs_getattr);
-int vfs_fstat(unsigned int fd, struct kstat *stat)
+/**
+ * vfs_statx_fd - Get the enhanced basic attributes by file descriptor
+ * @fd: The file descriptor referring to the file of interest
+ * @stat: The result structure to fill in.
+ * @request_mask: STATX_xxx flags indicating what the caller wants
+ * @query_flags: Query mode (KSTAT_QUERY_FLAGS)
+ *
+ * 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_statx_fd(unsigned int fd, struct kstat *stat,
+ u32 request_mask, unsigned int query_flags)
{
struct fd f = fdget_raw(fd);
int error = -EBADF;
if (f.file) {
- error = vfs_getattr(&f.file->f_path, stat);
+ error = vfs_getattr(&f.file->f_path, stat,
+ request_mask, query_flags);
fdput(f);
}
return error;
}
-EXPORT_SYMBOL(vfs_fstat);
+EXPORT_SYMBOL(vfs_statx_fd);
-int vfs_fstatat(int dfd, const char __user *filename, struct kstat *stat,
- int flag)
+/**
+ * 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.
+ *
+ * The caller must have preset stat->request_mask as for vfs_getattr(). The
+ * flags are also used to load up stat->query_flags.
+ *
+ * 0 will be returned on success, and a -ve error code if unsuccessful.
+ */
+int vfs_statx(int dfd, const char __user *filename, int flags,
+ struct kstat *stat, u32 request_mask)
{
struct path path;
int error = -EINVAL;
- unsigned int lookup_flags = 0;
+ unsigned int lookup_flags = LOOKUP_FOLLOW | LOOKUP_AUTOMOUNT;
- if ((flag & ~(AT_SYMLINK_NOFOLLOW | AT_NO_AUTOMOUNT |
- AT_EMPTY_PATH)) != 0)
- goto out;
+ if ((flags & ~(AT_SYMLINK_NOFOLLOW | AT_NO_AUTOMOUNT |
+ AT_EMPTY_PATH | KSTAT_QUERY_FLAGS)) != 0)
+ return -EINVAL;
- if (!(flag & AT_SYMLINK_NOFOLLOW))
- lookup_flags |= LOOKUP_FOLLOW;
- if (flag & AT_EMPTY_PATH)
+ 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;
+
retry:
error = user_path_at(dfd, filename, lookup_flags, &path);
if (error)
goto out;
- error = vfs_getattr(&path, stat);
+ error = vfs_getattr(&path, stat, request_mask, flags);
path_put(&path);
if (retry_estale(error, lookup_flags)) {
lookup_flags |= LOOKUP_REVAL;
@@ -116,19 +191,7 @@ retry:
out:
return error;
}
-EXPORT_SYMBOL(vfs_fstatat);
-
-int vfs_stat(const char __user *name, struct kstat *stat)
-{
- return vfs_fstatat(AT_FDCWD, name, stat, 0);
-}
-EXPORT_SYMBOL(vfs_stat);
-
-int vfs_lstat(const char __user *name, struct kstat *stat)
-{
- return vfs_fstatat(AT_FDCWD, name, stat, AT_SYMLINK_NOFOLLOW);
-}
-EXPORT_SYMBOL(vfs_lstat);
+EXPORT_SYMBOL(vfs_statx);
#ifdef __ARCH_WANT_OLD_STAT
@@ -141,7 +204,7 @@ static int cp_old_stat(struct kstat *stat, struct __old_kernel_stat __user * sta
{
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",
@@ -166,7 +229,7 @@ static int cp_old_stat(struct kstat *stat, struct __old_kernel_stat __user * sta
#if BITS_PER_LONG == 32
if (stat->size > MAX_NON_LFS)
return -EOVERFLOW;
-#endif
+#endif
tmp.st_size = stat->size;
tmp.st_atime = stat->atime.tv_sec;
tmp.st_mtime = stat->mtime.tv_sec;
@@ -445,6 +508,81 @@ SYSCALL_DEFINE4(fstatat64, int, dfd, const char __user *, filename,
}
#endif /* __ARCH_WANT_STAT64 || __ARCH_WANT_COMPAT_STAT64 */
+static inline int __put_timestamp(struct timespec *kts,
+ struct statx_timestamp __user *uts)
+{
+ return (__put_user(kts->tv_sec, &uts->tv_sec ) ||
+ __put_user(kts->tv_nsec, &uts->tv_nsec ) ||
+ __put_user(0, &uts->__reserved ));
+}
+
+/*
+ * Set the statx results.
+ */
+static long statx_set_result(struct kstat *stat, struct statx __user *buffer)
+{
+ uid_t uid = from_kuid_munged(current_user_ns(), stat->uid);
+ gid_t gid = from_kgid_munged(current_user_ns(), stat->gid);
+
+ if (__put_user(stat->result_mask, &buffer->stx_mask ) ||
+ __put_user(stat->mode, &buffer->stx_mode ) ||
+ __clear_user(&buffer->__spare0, sizeof(buffer->__spare0)) ||
+ __put_user(stat->nlink, &buffer->stx_nlink ) ||
+ __put_user(uid, &buffer->stx_uid ) ||
+ __put_user(gid, &buffer->stx_gid ) ||
+ __put_user(stat->attributes, &buffer->stx_attributes ) ||
+ __put_user(stat->blksize, &buffer->stx_blksize ) ||
+ __put_user(MAJOR(stat->rdev), &buffer->stx_rdev_major ) ||
+ __put_user(MINOR(stat->rdev), &buffer->stx_rdev_minor ) ||
+ __put_user(MAJOR(stat->dev), &buffer->stx_dev_major ) ||
+ __put_user(MINOR(stat->dev), &buffer->stx_dev_minor ) ||
+ __put_timestamp(&stat->atime, &buffer->stx_atime ) ||
+ __put_timestamp(&stat->btime, &buffer->stx_btime ) ||
+ __put_timestamp(&stat->ctime, &buffer->stx_ctime ) ||
+ __put_timestamp(&stat->mtime, &buffer->stx_mtime ) ||
+ __put_user(stat->ino, &buffer->stx_ino ) ||
+ __put_user(stat->size, &buffer->stx_size ) ||
+ __put_user(stat->blocks, &buffer->stx_blocks ) ||
+ __clear_user(&buffer->__spare1, sizeof(buffer->__spare1)) ||
+ __clear_user(&buffer->__spare2, sizeof(buffer->__spare2)))
+ return -EFAULT;
+
+ return 0;
+}
+
+/**
+ * sys_statx - System call to get enhanced stats
+ * @dfd: Base directory to pathwalk from *or* fd to stat.
+ * @filename: File to stat *or* NULL.
+ * @flags: AT_* flags to control pathwalk.
+ * @mask: Parts of statx struct actually required.
+ * @buffer: Result buffer.
+ *
+ * Note that if filename is NULL, then it does the equivalent of fstat() using
+ * dfd to indicate the file of interest.
+ */
+SYSCALL_DEFINE5(statx,
+ int, dfd, const char __user *, filename, unsigned, flags,
+ unsigned int, mask,
+ struct statx __user *, buffer)
+{
+ struct kstat stat;
+ int error;
+
+ if ((flags & AT_STATX_SYNC_TYPE) == AT_STATX_SYNC_TYPE)
+ return -EINVAL;
+ if (!access_ok(VERIFY_WRITE, buffer, sizeof(*buffer)))
+ return -EFAULT;
+
+ if (filename)
+ error = vfs_statx(dfd, filename, flags, &stat, mask);
+ else
+ error = vfs_statx_fd(dfd, &stat, mask, flags);
+ if (error)
+ return error;
+ return statx_set_result(&stat, buffer);
+}
+
/* Caller is here responsible for sufficient locking (ie. inode->i_lock) */
void __inode_add_bytes(struct inode *inode, loff_t bytes)
{