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-rw-r--r--fs/stat.c410
1 files changed, 410 insertions, 0 deletions
diff --git a/fs/stat.c b/fs/stat.c
new file mode 100644
index 00000000000..b8a0e5110ab
--- /dev/null
+++ b/fs/stat.c
@@ -0,0 +1,410 @@
+/*
+ * linux/fs/stat.c
+ *
+ * Copyright (C) 1991, 1992 Linus Torvalds
+ */
+
+#include <linux/config.h>
+#include <linux/module.h>
+#include <linux/mm.h>
+#include <linux/errno.h>
+#include <linux/file.h>
+#include <linux/smp_lock.h>
+#include <linux/highuid.h>
+#include <linux/fs.h>
+#include <linux/namei.h>
+#include <linux/security.h>
+#include <linux/syscalls.h>
+
+#include <asm/uaccess.h>
+#include <asm/unistd.h>
+
+void generic_fillattr(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 = inode->i_uid;
+ stat->gid = inode->i_gid;
+ stat->rdev = inode->i_rdev;
+ stat->atime = inode->i_atime;
+ stat->mtime = inode->i_mtime;
+ stat->ctime = inode->i_ctime;
+ stat->size = i_size_read(inode);
+ stat->blocks = inode->i_blocks;
+ stat->blksize = inode->i_blksize;
+}
+
+EXPORT_SYMBOL(generic_fillattr);
+
+int vfs_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat)
+{
+ struct inode *inode = dentry->d_inode;
+ int retval;
+
+ retval = security_inode_getattr(mnt, dentry);
+ if (retval)
+ return retval;
+
+ if (inode->i_op->getattr)
+ return inode->i_op->getattr(mnt, dentry, stat);
+
+ generic_fillattr(inode, stat);
+ if (!stat->blksize) {
+ struct super_block *s = inode->i_sb;
+ unsigned blocks;
+ blocks = (stat->size+s->s_blocksize-1) >> s->s_blocksize_bits;
+ stat->blocks = (s->s_blocksize / 512) * blocks;
+ stat->blksize = s->s_blocksize;
+ }
+ return 0;
+}
+
+EXPORT_SYMBOL(vfs_getattr);
+
+int vfs_stat(char __user *name, struct kstat *stat)
+{
+ struct nameidata nd;
+ int error;
+
+ error = user_path_walk(name, &nd);
+ if (!error) {
+ error = vfs_getattr(nd.mnt, nd.dentry, stat);
+ path_release(&nd);
+ }
+ return error;
+}
+
+EXPORT_SYMBOL(vfs_stat);
+
+int vfs_lstat(char __user *name, struct kstat *stat)
+{
+ struct nameidata nd;
+ int error;
+
+ error = user_path_walk_link(name, &nd);
+ if (!error) {
+ error = vfs_getattr(nd.mnt, nd.dentry, stat);
+ path_release(&nd);
+ }
+ return error;
+}
+
+EXPORT_SYMBOL(vfs_lstat);
+
+int vfs_fstat(unsigned int fd, struct kstat *stat)
+{
+ struct file *f = fget(fd);
+ int error = -EBADF;
+
+ if (f) {
+ error = vfs_getattr(f->f_vfsmnt, f->f_dentry, stat);
+ fput(f);
+ }
+ return error;
+}
+
+EXPORT_SYMBOL(vfs_fstat);
+
+#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;
+ tmp.st_mode = stat->mode;
+ tmp.st_nlink = stat->nlink;
+ if (tmp.st_nlink != stat->nlink)
+ return -EOVERFLOW;
+ SET_UID(tmp.st_uid, stat->uid);
+ SET_GID(tmp.st_gid, 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;
+}
+
+asmlinkage long sys_stat(char __user * filename, struct __old_kernel_stat __user * statbuf)
+{
+ struct kstat stat;
+ int error = vfs_stat(filename, &stat);
+
+ if (!error)
+ error = cp_old_stat(&stat, statbuf);
+
+ return error;
+}
+asmlinkage long sys_lstat(char __user * filename, struct __old_kernel_stat __user * statbuf)
+{
+ struct kstat stat;
+ int error = vfs_lstat(filename, &stat);
+
+ if (!error)
+ error = cp_old_stat(&stat, statbuf);
+
+ return error;
+}
+asmlinkage long sys_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 */
+
+static int cp_new_stat(struct kstat *stat, struct stat __user *statbuf)
+{
+ struct stat tmp;
+
+#if BITS_PER_LONG == 32
+ if (!old_valid_dev(stat->dev) || !old_valid_dev(stat->rdev))
+ return -EOVERFLOW;
+#else
+ if (!new_valid_dev(stat->dev) || !new_valid_dev(stat->rdev))
+ return -EOVERFLOW;
+#endif
+
+ memset(&tmp, 0, sizeof(tmp));
+#if BITS_PER_LONG == 32
+ tmp.st_dev = old_encode_dev(stat->dev);
+#else
+ tmp.st_dev = new_encode_dev(stat->dev);
+#endif
+ tmp.st_ino = stat->ino;
+ tmp.st_mode = stat->mode;
+ tmp.st_nlink = stat->nlink;
+ if (tmp.st_nlink != stat->nlink)
+ return -EOVERFLOW;
+ SET_UID(tmp.st_uid, stat->uid);
+ SET_GID(tmp.st_gid, stat->gid);
+#if BITS_PER_LONG == 32
+ tmp.st_rdev = old_encode_dev(stat->rdev);
+#else
+ tmp.st_rdev = new_encode_dev(stat->rdev);
+#endif
+#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;
+#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;
+}
+
+asmlinkage long sys_newstat(char __user * filename, struct stat __user * statbuf)
+{
+ struct kstat stat;
+ int error = vfs_stat(filename, &stat);
+
+ if (!error)
+ error = cp_new_stat(&stat, statbuf);
+
+ return error;
+}
+asmlinkage long sys_newlstat(char __user * filename, struct stat __user * statbuf)
+{
+ struct kstat stat;
+ int error = vfs_lstat(filename, &stat);
+
+ if (!error)
+ error = cp_new_stat(&stat, statbuf);
+
+ return error;
+}
+asmlinkage long sys_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;
+}
+
+asmlinkage long sys_readlink(const char __user * path, char __user * buf, int bufsiz)
+{
+ struct nameidata nd;
+ int error;
+
+ if (bufsiz <= 0)
+ return -EINVAL;
+
+ error = user_path_walk_link(path, &nd);
+ if (!error) {
+ struct inode * inode = nd.dentry->d_inode;
+
+ error = -EINVAL;
+ if (inode->i_op && inode->i_op->readlink) {
+ error = security_inode_readlink(nd.dentry);
+ if (!error) {
+ touch_atime(nd.mnt, nd.dentry);
+ error = inode->i_op->readlink(nd.dentry, buf, bufsiz);
+ }
+ }
+ path_release(&nd);
+ }
+ return error;
+}
+
+
+/* ---------- LFS-64 ----------- */
+#ifdef __ARCH_WANT_STAT64
+
+static long cp_new_stat64(struct kstat *stat, struct stat64 __user *statbuf)
+{
+ struct stat64 tmp;
+
+ memset(&tmp, 0, sizeof(struct stat64));
+#ifdef CONFIG_MIPS
+ /* mips has weird padding, so we don't get 64 bits there */
+ if (!new_valid_dev(stat->dev) || !new_valid_dev(stat->rdev))
+ return -EOVERFLOW;
+ 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;
+#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 = stat->uid;
+ tmp.st_gid = 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;
+}
+
+asmlinkage long sys_stat64(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;
+}
+asmlinkage long sys_lstat64(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;
+}
+asmlinkage long sys_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;
+}
+
+#endif /* __ARCH_WANT_STAT64 */
+
+void inode_add_bytes(struct inode *inode, loff_t bytes)
+{
+ spin_lock(&inode->i_lock);
+ inode->i_blocks += bytes >> 9;
+ bytes &= 511;
+ inode->i_bytes += bytes;
+ if (inode->i_bytes >= 512) {
+ inode->i_blocks++;
+ inode->i_bytes -= 512;
+ }
+ spin_unlock(&inode->i_lock);
+}
+
+EXPORT_SYMBOL(inode_add_bytes);
+
+void inode_sub_bytes(struct inode *inode, loff_t bytes)
+{
+ spin_lock(&inode->i_lock);
+ inode->i_blocks -= bytes >> 9;
+ bytes &= 511;
+ if (inode->i_bytes < bytes) {
+ inode->i_blocks--;
+ inode->i_bytes += 512;
+ }
+ inode->i_bytes -= 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 = (((loff_t)inode->i_blocks) << 9) + inode->i_bytes;
+ 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);
generated by cgit v1.2.3-18-g5258 (git 2.32.0) at 2024-11-24 22:47:22 +0000