#include <linux/namei.h>
#include <linux/quotaops.h>
#include <linux/pagemap.h>
-#include <linux/dnotify.h>
+#include <linux/fsnotify.h>
#include <linux/smp_lock.h>
#include <linux/personality.h>
#include <linux/security.h>
+#include <linux/syscalls.h>
#include <linux/mount.h>
#include <linux/audit.h>
+#include <linux/capability.h>
+#include <linux/file.h>
+#include <linux/fcntl.h>
+#include <linux/namei.h>
+#include <linux/proc_fs.h>
+#include <linux/vserver/inode.h>
#include <linux/vs_base.h>
-
+#include <linux/vs_tag.h>
+#include <linux/vs_cowbl.h>
#include <asm/namei.h>
#include <asm/uaccess.h>
*/
/*
* [Sep 2001 AV] Single-semaphore locking scheme (kudos to David Holland)
- * implemented. Let's see if raised priority of ->s_vfs_rename_sem gives
+ * implemented. Let's see if raised priority of ->s_vfs_rename_mutex gives
* any extra contention...
*/
* POSIX.1 2.4: an empty pathname is invalid (ENOENT).
* PATH_MAX includes the nul terminator --RR.
*/
-static inline int do_getname(const char __user *filename, char *page)
+static int do_getname(const char __user *filename, char *page)
{
int retval;
unsigned long len = PATH_MAX;
- if ((unsigned long) filename >= TASK_SIZE) {
- if (!segment_eq(get_fs(), KERNEL_DS))
+ if (!segment_eq(get_fs(), KERNEL_DS)) {
+ if ((unsigned long) filename >= TASK_SIZE)
return -EFAULT;
- } else if (TASK_SIZE - (unsigned long) filename < PATH_MAX)
- len = TASK_SIZE - (unsigned long) filename;
+ if (TASK_SIZE - (unsigned long) filename < PATH_MAX)
+ len = TASK_SIZE - (unsigned long) filename;
+ }
- retval = strncpy_from_user((char *)page, filename, len);
+ retval = strncpy_from_user(page, filename, len);
if (retval > 0) {
if (retval < len)
return 0;
result = ERR_PTR(retval);
}
}
- if (unlikely(current->audit_context) && !IS_ERR(result) && result)
- audit_getname(result);
+ audit_getname(result);
return result;
}
-/*
- * vfs_permission()
+#ifdef CONFIG_AUDITSYSCALL
+void putname(const char *name)
+{
+ if (unlikely(!audit_dummy_context()))
+ audit_putname(name);
+ else
+ __putname(name);
+}
+EXPORT_SYMBOL(putname);
+#endif
+
+
+/**
+ * generic_permission - check for access rights on a Posix-like filesystem
+ * @inode: inode to check access rights for
+ * @mask: right to check for (%MAY_READ, %MAY_WRITE, %MAY_EXEC)
+ * @check_acl: optional callback to check for Posix ACLs
*
- * is used to check for read/write/execute permissions on a file.
+ * Used to check for read/write/execute permissions on a file.
* We use "fsuid" for this, letting us set arbitrary permissions
* for filesystem access without changing the "normal" uids which
* are used for other things..
*/
-int vfs_permission(struct inode * inode, int mask)
+int generic_permission(struct inode *inode, int mask,
+ int (*check_acl)(struct inode *inode, int mask))
{
umode_t mode = inode->i_mode;
- if (mask & MAY_WRITE) {
- /*
- * Nobody gets write access to a read-only fs.
- */
- if (IS_RDONLY(inode) &&
- (S_ISREG(mode) || S_ISDIR(mode) || S_ISLNK(mode)))
- return -EROFS;
-
- /*
- * Nobody gets write access to an immutable file.
- */
- if (IS_IMMUTABLE(inode))
- return -EACCES;
- }
-
if (current->fsuid == inode->i_uid)
mode >>= 6;
- else if (in_group_p(inode->i_gid))
- mode >>= 3;
+ else {
+ if (IS_POSIXACL(inode) && (mode & S_IRWXG) && check_acl) {
+ int error = check_acl(inode, mask);
+ if (error == -EACCES)
+ goto check_capabilities;
+ else if (error != -EAGAIN)
+ return error;
+ }
+
+ if (in_group_p(inode->i_gid))
+ mode >>= 3;
+ }
/*
* If the DACs are ok we don't need any capability check.
if (((mode & mask & (MAY_READ|MAY_WRITE|MAY_EXEC)) == mask))
return 0;
+ check_capabilities:
/*
* Read/write DACs are always overridable.
* Executable DACs are overridable if at least one exec bit is set.
return -EACCES;
}
-int permission(struct inode * inode,int mask, struct nameidata *nd)
+static inline int dx_barrier(struct inode *inode)
{
- int retval;
- int submask;
- umode_t mode = inode->i_mode;
+ if (IS_BARRIER(inode) && !vx_check(0, VS_ADMIN)) {
+ vxwprintk(1, "xid=%d did hit the barrier.",
+ vx_current_xid());
+ return 1;
+ }
+ return 0;
+}
- /* Ordinary permission routines do not understand MAY_APPEND. */
- submask = mask & ~MAY_APPEND;
+static inline int dx_permission(struct inode *inode, int mask, struct nameidata *nd)
+{
+ if (dx_barrier(inode))
+ return -EACCES;
+ if (inode->i_tag == 0)
+ return 0;
+#ifdef CONFIG_VSERVER_FILESHARING
+ /* MEF: PlanetLab FS module assumes that any file that can be
+ * named (e.g., via a cross mount) is not hidden from another
+ * context or the admin context.
+ */
+ if (!dx_check(inode->i_tag, DX_HOSTID))
+ return 0;
+#endif
+ if (dx_check(inode->i_tag, DX_ADMIN|DX_WATCH|DX_IDENT))
+ return 0;
- if (nd && (mask & MAY_WRITE) && MNT_IS_RDONLY(nd->mnt) &&
- (S_ISREG(mode) || S_ISDIR(mode) || S_ISLNK(mode)))
- return -EROFS;
+ vxwprintk(1, "xid=%d denied access to %p[#%d,%lu] »%s«.",
+ vx_current_xid(), inode, inode->i_tag, inode->i_ino,
+ vxd_cond_path(nd));
+ return -EACCES;
+}
+
+int permission(struct inode *inode, int mask, struct nameidata *nd)
+{
+ umode_t mode = inode->i_mode;
+ int retval, submask;
+
+ if (mask & MAY_WRITE) {
+
+ /*
+ * Nobody gets write access to a read-only fs.
+ */
+ if ((IS_RDONLY(inode) || (nd && MNT_IS_RDONLY(nd->mnt))) &&
+ (S_ISREG(mode) || S_ISDIR(mode) || S_ISLNK(mode)))
+ return -EROFS;
+
+ /*
+ * Nobody gets write access to an immutable file.
+ */
+ if (IS_IMMUTABLE(inode) && !IS_COW(inode))
+ return -EACCES;
+ }
+
+
+ /*
+ * MAY_EXEC on regular files requires special handling: We override
+ * filesystem execute permissions if the mode bits aren't set or
+ * the fs is mounted with the "noexec" flag.
+ */
+ if ((mask & MAY_EXEC) && S_ISREG(mode) && (!(mode & S_IXUGO) ||
+ (nd && nd->mnt && (nd->mnt->mnt_flags & MNT_NOEXEC))))
+ return -EACCES;
+ /* Ordinary permission routines do not understand MAY_APPEND. */
+ submask = mask & ~MAY_APPEND;
+ if ((retval = dx_permission(inode, mask, nd)))
+ return retval;
if (inode->i_op && inode->i_op->permission)
retval = inode->i_op->permission(inode, submask, nd);
else
- retval = vfs_permission(inode, submask);
+ retval = generic_permission(inode, submask, NULL);
if (retval)
return retval;
return security_inode_permission(inode, mask, nd);
}
+/**
+ * vfs_permission - check for access rights to a given path
+ * @nd: lookup result that describes the path
+ * @mask: right to check for (%MAY_READ, %MAY_WRITE, %MAY_EXEC)
+ *
+ * Used to check for read/write/execute permissions on a path.
+ * We use "fsuid" for this, letting us set arbitrary permissions
+ * for filesystem access without changing the "normal" uids which
+ * are used for other things.
+ */
+int vfs_permission(struct nameidata *nd, int mask)
+{
+ return permission(nd->dentry->d_inode, mask, nd);
+}
+
+/**
+ * file_permission - check for additional access rights to a given file
+ * @file: file to check access rights for
+ * @mask: right to check for (%MAY_READ, %MAY_WRITE, %MAY_EXEC)
+ *
+ * Used to check for read/write/execute permissions on an already opened
+ * file.
+ *
+ * Note:
+ * Do not use this function in new code. All access checks should
+ * be done using vfs_permission().
+ */
+int file_permission(struct file *file, int mask)
+{
+ return permission(file->f_path.dentry->d_inode, mask, NULL);
+}
+
/*
* get_write_access() gets write permission for a file.
* put_write_access() releases this write permission.
int deny_write_access(struct file * file)
{
- struct inode *inode = file->f_dentry->d_inode;
+ struct inode *inode = file->f_path.dentry->d_inode;
spin_lock(&inode->i_lock);
if (atomic_read(&inode->i_writecount) > 0) {
void path_release_on_umount(struct nameidata *nd)
{
dput(nd->dentry);
- _mntput(nd->mnt);
+ mntput_no_expire(nd->mnt);
+}
+
+/**
+ * release_open_intent - free up open intent resources
+ * @nd: pointer to nameidata
+ */
+void release_open_intent(struct nameidata *nd)
+{
+ if (nd->intent.open.file->f_path.dentry == NULL)
+ put_filp(nd->intent.open.file);
+ else
+ fput(nd->intent.open.file);
+}
+
+static inline struct dentry *
+do_revalidate(struct dentry *dentry, struct nameidata *nd)
+{
+ int status = dentry->d_op->d_revalidate(dentry, nd);
+ if (unlikely(status <= 0)) {
+ /*
+ * The dentry failed validation.
+ * If d_revalidate returned 0 attempt to invalidate
+ * the dentry otherwise d_revalidate is asking us
+ * to return a fail status.
+ */
+ if (!status) {
+ if (!d_invalidate(dentry)) {
+ dput(dentry);
+ dentry = NULL;
+ }
+ } else {
+ dput(dentry);
+ dentry = ERR_PTR(status);
+ }
+ }
+ return dentry;
}
/*
if (!dentry)
dentry = d_lookup(parent, name);
- if (dentry && dentry->d_op && dentry->d_op->d_revalidate) {
- if (!dentry->d_op->d_revalidate(dentry, nd) && !d_invalidate(dentry)) {
- dput(dentry);
- dentry = NULL;
- }
- }
+ if (dentry && dentry->d_op && dentry->d_op->d_revalidate)
+ dentry = do_revalidate(dentry, nd);
+
return dentry;
}
/*
* Short-cut version of permission(), for calling by
* path_walk(), when dcache lock is held. Combines parts
- * of permission() and vfs_permission(), and tests ONLY for
+ * of permission() and generic_permission(), and tests ONLY for
* MAY_EXEC permission.
*
* If appropriate, check DAC only. If not appropriate, or
* short-cut DAC fails, then call permission() to do more
* complete permission check.
*/
-static inline int exec_permission_lite(struct inode *inode,
+static int exec_permission_lite(struct inode *inode,
struct nameidata *nd)
{
umode_t mode = inode->i_mode;
+ if (dx_barrier(inode))
+ return -EACCES;
if (inode->i_op && inode->i_op->permission)
return -EAGAIN;
struct dentry * result;
struct inode *dir = parent->d_inode;
- down(&dir->i_sem);
+ mutex_lock(&dir->i_mutex);
/*
* First re-do the cached lookup just in case it was created
* while we waited for the directory semaphore..
else
result = dentry;
}
- up(&dir->i_sem);
+ mutex_unlock(&dir->i_mutex);
return result;
}
* Uhhuh! Nasty case: the cache was re-populated while
* we waited on the semaphore. Need to revalidate.
*/
- up(&dir->i_sem);
+ mutex_unlock(&dir->i_mutex);
if (result->d_op && result->d_op->d_revalidate) {
- if (!result->d_op->d_revalidate(result, nd) && !d_invalidate(result)) {
- dput(result);
+ result = do_revalidate(result, nd);
+ if (!result)
result = ERR_PTR(-ENOENT);
- }
}
return result;
}
static int __emul_lookup_dentry(const char *, struct nameidata *);
/* SMP-safe */
-static inline int
+static __always_inline int
walk_init_root(const char *name, struct nameidata *nd)
{
- read_lock(¤t->fs->lock);
- if (current->fs->altroot && !(nd->flags & LOOKUP_NOALT)) {
- nd->mnt = mntget(current->fs->altrootmnt);
- nd->dentry = dget(current->fs->altroot);
- read_unlock(¤t->fs->lock);
+ struct fs_struct *fs = current->fs;
+
+ read_lock(&fs->lock);
+ if (fs->altroot && !(nd->flags & LOOKUP_NOALT)) {
+ nd->mnt = mntget(fs->altrootmnt);
+ nd->dentry = dget(fs->altroot);
+ read_unlock(&fs->lock);
if (__emul_lookup_dentry(name,nd))
return 0;
- read_lock(¤t->fs->lock);
+ read_lock(&fs->lock);
}
- nd->mnt = mntget(current->fs->rootmnt);
- nd->dentry = dget(current->fs->root);
- read_unlock(¤t->fs->lock);
+ nd->mnt = mntget(fs->rootmnt);
+ nd->dentry = dget(fs->root);
+ read_unlock(&fs->lock);
return 1;
}
-static inline int __vfs_follow_link(struct nameidata *nd, const char *link)
+static __always_inline int __vfs_follow_link(struct nameidata *nd, const char *link)
{
int res = 0;
char *name;
return PTR_ERR(link);
}
+static inline void dput_path(struct path *path, struct nameidata *nd)
+{
+ dput(path->dentry);
+ if (path->mnt != nd->mnt)
+ mntput(path->mnt);
+}
+
+static inline void path_to_nameidata(struct path *path, struct nameidata *nd)
+{
+ dput(nd->dentry);
+ if (nd->mnt != path->mnt)
+ mntput(nd->mnt);
+ nd->mnt = path->mnt;
+ nd->dentry = path->dentry;
+}
+
+static __always_inline int __do_follow_link(struct path *path, struct nameidata *nd)
+{
+ int error;
+ void *cookie;
+ struct dentry *dentry = path->dentry;
+
+ touch_atime(path->mnt, dentry);
+ nd_set_link(nd, NULL);
+
+ if (path->mnt != nd->mnt) {
+ path_to_nameidata(path, nd);
+ dget(dentry);
+ }
+ mntget(path->mnt);
+ cookie = dentry->d_inode->i_op->follow_link(dentry, nd);
+ error = PTR_ERR(cookie);
+ if (!IS_ERR(cookie)) {
+ char *s = nd_get_link(nd);
+ error = 0;
+ if (s)
+ error = __vfs_follow_link(nd, s);
+ if (dentry->d_inode->i_op->put_link)
+ dentry->d_inode->i_op->put_link(dentry, nd, cookie);
+ }
+ dput(dentry);
+ mntput(path->mnt);
+
+ return error;
+}
+
/*
* This limits recursive symlink follows to 8, while
* limiting consecutive symlinks to 40.
* Without that kind of total limit, nasty chains of consecutive
* symlinks can cause almost arbitrarily long lookups.
*/
-static inline int do_follow_link(struct dentry *dentry, struct nameidata *nd)
+static inline int do_follow_link(struct path *path, struct nameidata *nd)
{
int err = -ELOOP;
if (current->link_count >= MAX_NESTED_LINKS)
goto loop;
BUG_ON(nd->depth >= MAX_NESTED_LINKS);
cond_resched();
- err = security_inode_follow_link(dentry, nd);
+ err = security_inode_follow_link(path->dentry, nd);
if (err)
goto loop;
current->link_count++;
current->total_link_count++;
nd->depth++;
- touch_atime(nd->mnt, dentry);
- nd_set_link(nd, NULL);
- err = dentry->d_inode->i_op->follow_link(dentry, nd);
- if (!err) {
- char *s = nd_get_link(nd);
- if (s)
- err = __vfs_follow_link(nd, s);
- if (dentry->d_inode->i_op->put_link)
- dentry->d_inode->i_op->put_link(dentry, nd);
- }
+ err = __do_follow_link(path, nd);
current->link_count--;
nd->depth--;
return err;
loop:
+ dput_path(path, nd);
path_release(nd);
return err;
}
/* no need for dcache_lock, as serialization is taken care in
* namespace.c
*/
-static int follow_mount(struct vfsmount **mnt, struct dentry **dentry)
+static int __follow_mount(struct path *path)
{
int res = 0;
+ while (d_mountpoint(path->dentry)) {
+ struct vfsmount *mounted = lookup_mnt(path->mnt, path->dentry);
+ if (!mounted)
+ break;
+ dput(path->dentry);
+ if (res)
+ mntput(path->mnt);
+ path->mnt = mounted;
+ path->dentry = dget(mounted->mnt_root);
+ res = 1;
+ }
+ return res;
+}
+
+static void follow_mount(struct vfsmount **mnt, struct dentry **dentry)
+{
while (d_mountpoint(*dentry)) {
struct vfsmount *mounted = lookup_mnt(*mnt, *dentry);
if (!mounted)
break;
+ dput(*dentry);
mntput(*mnt);
*mnt = mounted;
- dput(*dentry);
*dentry = dget(mounted->mnt_root);
- res = 1;
}
- return res;
}
/* no need for dcache_lock, as serialization is taken care in
* namespace.c
*/
-static inline int __follow_down(struct vfsmount **mnt, struct dentry **dentry)
+int follow_down(struct vfsmount **mnt, struct dentry **dentry)
{
struct vfsmount *mounted;
mounted = lookup_mnt(*mnt, *dentry);
if (mounted) {
+ dput(*dentry);
mntput(*mnt);
*mnt = mounted;
- dput(*dentry);
*dentry = dget(mounted->mnt_root);
return 1;
}
return 0;
}
-int follow_down(struct vfsmount **mnt, struct dentry **dentry)
-{
- return __follow_down(mnt,dentry);
-}
-
-static inline void follow_dotdot(struct vfsmount **mnt, struct dentry **dentry)
+static __always_inline void follow_dotdot(struct nameidata *nd)
{
+ struct fs_struct *fs = current->fs;
+
while(1) {
struct vfsmount *parent;
- struct dentry *old = *dentry;
-
- read_lock(¤t->fs->lock);
- if (*dentry == current->fs->root &&
- *mnt == current->fs->rootmnt) {
- read_unlock(¤t->fs->lock);
- break;
+ struct dentry *old = nd->dentry;
+
+ read_lock(&fs->lock);
+ if (nd->dentry == fs->root &&
+ nd->mnt == fs->rootmnt) {
+ read_unlock(&fs->lock);
+ /* for sane '/' avoid follow_mount() */
+ return;
}
- read_unlock(¤t->fs->lock);
+ read_unlock(&fs->lock);
spin_lock(&dcache_lock);
- if (*dentry != (*mnt)->mnt_root) {
- *dentry = dget((*dentry)->d_parent);
+ if (nd->dentry != nd->mnt->mnt_root) {
+ nd->dentry = dget(nd->dentry->d_parent);
spin_unlock(&dcache_lock);
dput(old);
break;
}
spin_unlock(&dcache_lock);
spin_lock(&vfsmount_lock);
- parent = (*mnt)->mnt_parent;
- if (parent == *mnt) {
+ parent = nd->mnt->mnt_parent;
+ if (parent == nd->mnt) {
spin_unlock(&vfsmount_lock);
break;
}
mntget(parent);
- *dentry = dget((*mnt)->mnt_mountpoint);
+ nd->dentry = dget(nd->mnt->mnt_mountpoint);
spin_unlock(&vfsmount_lock);
dput(old);
- mntput(*mnt);
- *mnt = parent;
+ mntput(nd->mnt);
+ nd->mnt = parent;
}
- follow_mount(mnt, dentry);
+ follow_mount(&nd->mnt, &nd->dentry);
}
-struct path {
- struct vfsmount *mnt;
- struct dentry *dentry;
-};
-
/*
* It's more convoluted than I'd like it to be, but... it's still fairly
* small and for now I'd prefer to have fast path as straight as possible.
{
struct vfsmount *mnt = nd->mnt;
struct dentry *dentry = __d_lookup(nd->dentry, name);
+ struct inode *inode;
if (!dentry)
goto need_lookup;
if (dentry->d_op && dentry->d_op->d_revalidate)
goto need_revalidate;
+ inode = dentry->d_inode;
+ if (!inode)
+ goto done;
+ if (inode->i_sb->s_magic == PROC_SUPER_MAGIC) {
+ struct proc_dir_entry *de = PDE(inode);
+
+ if (de && !vx_hide_check(0, de->vx_flags))
+ goto hidden;
+ }
+#ifdef CONFIG_VSERVER_FILESHARING
+ /* MEF: PlanetLab FS module assumes that any file that can be
+ * named (e.g., via a cross mount) is not hidden from another
+ * context or the admin context.
+ */
+ if (!dx_check(inode->i_tag, DX_HOSTID)) {
+ /* do nothing */
+ }
+ else /* do the following check */
+#endif
+ if (!dx_check(inode->i_tag, DX_WATCH|DX_ADMIN|DX_HOSTID|DX_IDENT))
+ goto hidden;
done:
path->mnt = mnt;
path->dentry = dentry;
+ __follow_mount(path);
return 0;
+hidden:
+ vxwprintk(1, "xid=%d did lookup hidden %p[#%d,%lu] »%s«.",
+ vx_current_xid(), inode, inode->i_tag, inode->i_ino,
+ vxd_path(dentry, mnt));
+ dput(dentry);
+ return -ENOENT;
need_lookup:
dentry = real_lookup(nd->dentry, name, nd);
goto done;
need_revalidate:
- if (dentry->d_op->d_revalidate(dentry, nd))
- goto done;
- if (d_invalidate(dentry))
- goto done;
- dput(dentry);
- goto need_lookup;
+ dentry = do_revalidate(dentry, nd);
+ if (!dentry)
+ goto need_lookup;
+ if (IS_ERR(dentry))
+ goto fail;
+ goto done;
fail:
return PTR_ERR(dentry);
/*
* Name resolution.
+ * This is the basic name resolution function, turning a pathname into
+ * the final dentry. We expect 'base' to be positive and a directory.
*
- * This is the basic name resolution function, turning a pathname
- * into the final dentry.
- *
- * We expect 'base' to be positive and a directory.
+ * Returns 0 and nd will have valid dentry and mnt on success.
+ * Returns error and drops reference to input namei data on failure.
*/
-int fastcall link_path_walk(const char * name, struct nameidata *nd)
+static fastcall int __link_path_walk(const char * name, struct nameidata *nd)
{
struct path next;
struct inode *inode;
- int err, atomic;
+ int err;
unsigned int lookup_flags = nd->flags;
-
- atomic = (lookup_flags & LOOKUP_ATOMIC);
-
+
while (*name=='/')
name++;
if (!*name)
inode = nd->dentry->d_inode;
if (nd->depth)
- lookup_flags = LOOKUP_FOLLOW;
+ lookup_flags = LOOKUP_FOLLOW | (nd->flags & LOOKUP_CONTINUE);
/* At this point we know we have a real path component. */
for(;;) {
struct qstr this;
unsigned int c;
+ nd->flags |= LOOKUP_CONTINUE;
err = exec_permission_lite(inode, nd);
- if (err == -EAGAIN) {
- err = permission(inode, MAY_EXEC, nd);
- }
+ if (err == -EAGAIN)
+ err = vfs_permission(nd, MAY_EXEC);
if (err)
break;
case 2:
if (this.name[1] != '.')
break;
- follow_dotdot(&nd->mnt, &nd->dentry);
+ follow_dotdot(nd);
inode = nd->dentry->d_inode;
/* fallthrough */
case 1:
if (err < 0)
break;
}
- err = -EWOULDBLOCKIO;
- if (atomic)
- break;
- nd->flags |= LOOKUP_CONTINUE;
/* This does the actual lookups.. */
err = do_lookup(nd, &this, &next);
if (err)
break;
- /* Check mountpoints.. */
- follow_mount(&next.mnt, &next.dentry);
err = -ENOENT;
inode = next.dentry->d_inode;
goto out_dput;
if (inode->i_op->follow_link) {
- mntget(next.mnt);
- err = do_follow_link(next.dentry, nd);
- dput(next.dentry);
- mntput(next.mnt);
+ err = do_follow_link(&next, nd);
if (err)
goto return_err;
err = -ENOENT;
err = -ENOTDIR;
if (!inode->i_op)
break;
- } else {
- dput(nd->dentry);
- nd->mnt = next.mnt;
- nd->dentry = next.dentry;
- }
+ } else
+ path_to_nameidata(&next, nd);
err = -ENOTDIR;
if (!inode->i_op->lookup)
break;
last_with_slashes:
lookup_flags |= LOOKUP_FOLLOW | LOOKUP_DIRECTORY;
last_component:
- nd->flags &= ~LOOKUP_CONTINUE;
+ /* Clear LOOKUP_CONTINUE iff it was previously unset */
+ nd->flags &= lookup_flags | ~LOOKUP_CONTINUE;
if (lookup_flags & LOOKUP_PARENT)
goto lookup_parent;
if (this.name[0] == '.') switch (this.len) {
case 2:
if (this.name[1] != '.')
break;
- follow_dotdot(&nd->mnt, &nd->dentry);
+ follow_dotdot(nd);
inode = nd->dentry->d_inode;
/* fallthrough */
case 1:
if (err < 0)
break;
}
- err = -EWOULDBLOCKIO;
- if (atomic)
- break;
err = do_lookup(nd, &this, &next);
if (err)
break;
- follow_mount(&next.mnt, &next.dentry);
inode = next.dentry->d_inode;
if ((lookup_flags & LOOKUP_FOLLOW)
&& inode && inode->i_op && inode->i_op->follow_link) {
- mntget(next.mnt);
- err = do_follow_link(next.dentry, nd);
- dput(next.dentry);
- mntput(next.mnt);
+ err = do_follow_link(&next, nd);
if (err)
goto return_err;
inode = nd->dentry->d_inode;
- } else {
- dput(nd->dentry);
- nd->mnt = next.mnt;
- nd->dentry = next.dentry;
- }
+ } else
+ path_to_nameidata(&next, nd);
err = -ENOENT;
if (!inode)
break;
return_base:
return 0;
out_dput:
- dput(next.dentry);
+ dput_path(&next, nd);
break;
}
path_release(nd);
return err;
}
+/*
+ * Wrapper to retry pathname resolution whenever the underlying
+ * file system returns an ESTALE.
+ *
+ * Retry the whole path once, forcing real lookup requests
+ * instead of relying on the dcache.
+ */
+int fastcall link_path_walk(const char *name, struct nameidata *nd)
+{
+ struct nameidata save = *nd;
+ int result;
+
+ /* make sure the stuff we saved doesn't go away */
+ dget(save.dentry);
+ mntget(save.mnt);
+
+ result = __link_path_walk(name, nd);
+ if (result == -ESTALE) {
+ *nd = save;
+ dget(nd->dentry);
+ mntget(nd->mnt);
+ nd->flags |= LOOKUP_REVAL;
+ result = __link_path_walk(name, nd);
+ }
+
+ dput(save.dentry);
+ mntput(save.mnt);
+
+ return result;
+}
+
int fastcall path_walk(const char * name, struct nameidata *nd)
{
current->total_link_count = 0;
return link_path_walk(name, nd);
}
-/* SMP-safe */
-/* returns 1 if everything is done */
+/*
+ * SMP-safe: Returns 1 and nd will have valid dentry and mnt, if
+ * everything is done. Returns 0 and drops input nd, if lookup failed;
+ */
static int __emul_lookup_dentry(const char *name, struct nameidata *nd)
{
if (path_walk(name, nd))
struct vfsmount *old_mnt = nd->mnt;
struct qstr last = nd->last;
int last_type = nd->last_type;
+ struct fs_struct *fs = current->fs;
+
/*
- * NAME was not found in alternate root or it's a directory. Try to find
- * it in the normal root:
+ * NAME was not found in alternate root or it's a directory.
+ * Try to find it in the normal root:
*/
nd->last_type = LAST_ROOT;
- read_lock(¤t->fs->lock);
- nd->mnt = mntget(current->fs->rootmnt);
- nd->dentry = dget(current->fs->root);
- read_unlock(¤t->fs->lock);
+ read_lock(&fs->lock);
+ nd->mnt = mntget(fs->rootmnt);
+ nd->dentry = dget(fs->root);
+ read_unlock(&fs->lock);
if (path_walk(name, nd) == 0) {
if (nd->dentry->d_inode) {
dput(old_dentry);
struct vfsmount *mnt = NULL, *oldmnt;
struct dentry *dentry = NULL, *olddentry;
int err;
+ struct fs_struct *fs = current->fs;
if (!emul)
goto set_it;
dentry = nd.dentry;
}
set_it:
- write_lock(¤t->fs->lock);
- oldmnt = current->fs->altrootmnt;
- olddentry = current->fs->altroot;
- current->fs->altrootmnt = mnt;
- current->fs->altroot = dentry;
- write_unlock(¤t->fs->lock);
+ write_lock(&fs->lock);
+ oldmnt = fs->altrootmnt;
+ olddentry = fs->altroot;
+ fs->altrootmnt = mnt;
+ fs->altroot = dentry;
+ write_unlock(&fs->lock);
if (olddentry) {
dput(olddentry);
mntput(oldmnt);
}
}
-int fastcall path_lookup(const char *name, unsigned int flags, struct nameidata *nd)
+/* Returns 0 and nd will be valid on success; Retuns error, otherwise. */
+static int fastcall do_path_lookup(int dfd, const char *name,
+ unsigned int flags, struct nameidata *nd)
{
- int retval;
+ int retval = 0;
+ int fput_needed;
+ struct file *file;
+ struct fs_struct *fs = current->fs;
nd->last_type = LAST_ROOT; /* if there are only slashes... */
nd->flags = flags;
nd->depth = 0;
- read_lock(¤t->fs->lock);
if (*name=='/') {
- if (current->fs->altroot && !(nd->flags & LOOKUP_NOALT)) {
- nd->mnt = mntget(current->fs->altrootmnt);
- nd->dentry = dget(current->fs->altroot);
- read_unlock(¤t->fs->lock);
+ read_lock(&fs->lock);
+ if (fs->altroot && !(nd->flags & LOOKUP_NOALT)) {
+ nd->mnt = mntget(fs->altrootmnt);
+ nd->dentry = dget(fs->altroot);
+ read_unlock(&fs->lock);
if (__emul_lookup_dentry(name,nd))
- return 0;
- read_lock(¤t->fs->lock);
+ goto out; /* found in altroot */
+ read_lock(&fs->lock);
}
- nd->mnt = mntget(current->fs->rootmnt);
- nd->dentry = dget(current->fs->root);
+ nd->mnt = mntget(fs->rootmnt);
+ nd->dentry = dget(fs->root);
+ read_unlock(&fs->lock);
+ } else if (dfd == AT_FDCWD) {
+ read_lock(&fs->lock);
+ nd->mnt = mntget(fs->pwdmnt);
+ nd->dentry = dget(fs->pwd);
+ read_unlock(&fs->lock);
} else {
- nd->mnt = mntget(current->fs->pwdmnt);
- nd->dentry = dget(current->fs->pwd);
+ struct dentry *dentry;
+
+ file = fget_light(dfd, &fput_needed);
+ retval = -EBADF;
+ if (!file)
+ goto out_fail;
+
+ dentry = file->f_path.dentry;
+
+ retval = -ENOTDIR;
+ if (!S_ISDIR(dentry->d_inode->i_mode))
+ goto fput_fail;
+
+ retval = file_permission(file, MAY_EXEC);
+ if (retval)
+ goto fput_fail;
+
+ nd->mnt = mntget(file->f_path.mnt);
+ nd->dentry = dget(dentry);
+
+ fput_light(file, fput_needed);
}
- read_unlock(¤t->fs->lock);
current->total_link_count = 0;
retval = link_path_walk(name, nd);
- if (unlikely(current->audit_context
- && nd && nd->dentry && nd->dentry->d_inode))
- audit_inode(name,
- nd->dentry->d_inode->i_ino,
- nd->dentry->d_inode->i_rdev);
+out:
+ if (likely(retval == 0)) {
+ if (unlikely(!audit_dummy_context() && nd && nd->dentry &&
+ nd->dentry->d_inode))
+ audit_inode(name, nd->dentry->d_inode);
+ }
+out_fail:
return retval;
+
+fput_fail:
+ fput_light(file, fput_needed);
+ goto out_fail;
+}
+
+int fastcall path_lookup(const char *name, unsigned int flags,
+ struct nameidata *nd)
+{
+ return do_path_lookup(AT_FDCWD, name, flags, nd);
+}
+
+static int __path_lookup_intent_open(int dfd, const char *name,
+ unsigned int lookup_flags, struct nameidata *nd,
+ int open_flags, int create_mode)
+{
+ struct file *filp = get_empty_filp();
+ int err;
+
+ if (filp == NULL)
+ return -ENFILE;
+ nd->intent.open.file = filp;
+ nd->intent.open.flags = open_flags;
+ nd->intent.open.create_mode = create_mode;
+ err = do_path_lookup(dfd, name, lookup_flags|LOOKUP_OPEN, nd);
+ if (IS_ERR(nd->intent.open.file)) {
+ if (err == 0) {
+ err = PTR_ERR(nd->intent.open.file);
+ path_release(nd);
+ }
+ } else if (err != 0)
+ release_open_intent(nd);
+ return err;
+}
+
+/**
+ * path_lookup_open - lookup a file path with open intent
+ * @dfd: the directory to use as base, or AT_FDCWD
+ * @name: pointer to file name
+ * @lookup_flags: lookup intent flags
+ * @nd: pointer to nameidata
+ * @open_flags: open intent flags
+ */
+int path_lookup_open(int dfd, const char *name, unsigned int lookup_flags,
+ struct nameidata *nd, int open_flags)
+{
+ return __path_lookup_intent_open(dfd, name, lookup_flags, nd,
+ open_flags, 0);
+}
+
+/**
+ * path_lookup_create - lookup a file path with open + create intent
+ * @dfd: the directory to use as base, or AT_FDCWD
+ * @name: pointer to file name
+ * @lookup_flags: lookup intent flags
+ * @nd: pointer to nameidata
+ * @open_flags: open intent flags
+ * @create_mode: create intent flags
+ */
+static int path_lookup_create(int dfd, const char *name,
+ unsigned int lookup_flags, struct nameidata *nd,
+ int open_flags, int create_mode)
+{
+ return __path_lookup_intent_open(dfd, name, lookup_flags|LOOKUP_CREATE,
+ nd, open_flags, create_mode);
+}
+
+int __user_path_lookup_open(const char __user *name, unsigned int lookup_flags,
+ struct nameidata *nd, int open_flags)
+{
+ char *tmp = getname(name);
+ int err = PTR_ERR(tmp);
+
+ if (!IS_ERR(tmp)) {
+ err = __path_lookup_intent_open(AT_FDCWD, tmp, lookup_flags, nd, open_flags, 0);
+ putname(tmp);
+ }
+ return err;
}
/*
return dentry;
}
-struct dentry * lookup_hash(struct qstr *name, struct dentry * base)
+static struct dentry *lookup_hash(struct nameidata *nd)
{
- return __lookup_hash(name, base, NULL);
+ return __lookup_hash(&nd->last, nd->dentry, nd);
}
/* SMP-safe */
}
this.hash = end_name_hash(hash);
- return lookup_hash(&this, base);
+ return __lookup_hash(&this, base, NULL);
access:
return ERR_PTR(-EACCES);
}
* that namei follows links, while lnamei does not.
* SMP-safe
*/
-int fastcall __user_walk(const char __user *name, unsigned flags, struct nameidata *nd)
+int fastcall __user_walk_fd(int dfd, const char __user *name, unsigned flags,
+ struct nameidata *nd)
{
char *tmp = getname(name);
int err = PTR_ERR(tmp);
if (!IS_ERR(tmp)) {
- err = path_lookup(tmp, flags, nd);
+ err = do_path_lookup(dfd, tmp, flags, nd);
putname(tmp);
}
return err;
}
+int fastcall __user_walk(const char __user *name, unsigned flags, struct nameidata *nd)
+{
+ return __user_walk_fd(AT_FDCWD, name, flags, nd);
+}
+
/*
* It's inline, so penalty for filesystems that don't use sticky bit is
* minimal.
* 10. We don't allow removal of NFS sillyrenamed files; it's handled by
* nfs_async_unlink().
*/
-static inline int may_delete(struct inode *dir,struct dentry *victim,int isdir)
+static int may_delete(struct inode *dir, struct dentry *victim,
+ int isdir, struct nameidata *nd)
{
int error;
+
if (!victim->d_inode)
return -ENOENT;
- if (victim->d_parent->d_inode != dir)
- BUG();
-
- error = permission(dir,MAY_WRITE | MAY_EXEC, NULL);
+
+ BUG_ON(victim->d_parent->d_inode != dir);
+ audit_inode_child(victim->d_name.name, victim->d_inode, dir);
+
+ error = permission(dir,MAY_WRITE | MAY_EXEC, nd);
if (error)
return error;
if (IS_APPEND(dir))
return permission(dir,MAY_WRITE | MAY_EXEC, nd);
}
-static inline int mnt_may_create(struct vfsmount *mnt, struct inode *dir, struct dentry *child) {
- if (child->d_inode)
- return -EEXIST;
- if (IS_DEADDIR(dir))
- return -ENOENT;
- if (mnt->mnt_flags & MNT_RDONLY)
- return -EROFS;
- return 0;
-}
-
-static inline int mnt_may_unlink(struct vfsmount *mnt, struct inode *dir, struct dentry *child) {
- if (!child->d_inode)
- return -ENOENT;
- if (mnt->mnt_flags & MNT_RDONLY)
- return -EROFS;
- return 0;
-}
-
/*
- * Special case: O_CREAT|O_EXCL implies O_NOFOLLOW for security
- * reasons.
- *
* O_DIRECTORY translates into forcing a directory lookup.
*/
static inline int lookup_flags(unsigned int f)
if (f & O_NOFOLLOW)
retval &= ~LOOKUP_FOLLOW;
- if ((f & (O_CREAT|O_EXCL)) == (O_CREAT|O_EXCL))
- retval &= ~LOOKUP_FOLLOW;
-
if (f & O_DIRECTORY)
retval |= LOOKUP_DIRECTORY;
- if (f & O_ATOMICLOOKUP)
- retval |= LOOKUP_ATOMIC;
return retval;
}
struct dentry *p;
if (p1 == p2) {
- down(&p1->d_inode->i_sem);
+ mutex_lock_nested(&p1->d_inode->i_mutex, I_MUTEX_PARENT);
return NULL;
}
- down(&p1->d_inode->i_sb->s_vfs_rename_sem);
+ mutex_lock(&p1->d_inode->i_sb->s_vfs_rename_mutex);
for (p = p1; p->d_parent != p; p = p->d_parent) {
if (p->d_parent == p2) {
- down(&p2->d_inode->i_sem);
- down(&p1->d_inode->i_sem);
+ mutex_lock_nested(&p2->d_inode->i_mutex, I_MUTEX_PARENT);
+ mutex_lock_nested(&p1->d_inode->i_mutex, I_MUTEX_CHILD);
return p;
}
}
for (p = p2; p->d_parent != p; p = p->d_parent) {
if (p->d_parent == p1) {
- down(&p1->d_inode->i_sem);
- down(&p2->d_inode->i_sem);
+ mutex_lock_nested(&p1->d_inode->i_mutex, I_MUTEX_PARENT);
+ mutex_lock_nested(&p2->d_inode->i_mutex, I_MUTEX_CHILD);
return p;
}
}
- down(&p1->d_inode->i_sem);
- down(&p2->d_inode->i_sem);
+ mutex_lock_nested(&p1->d_inode->i_mutex, I_MUTEX_PARENT);
+ mutex_lock_nested(&p2->d_inode->i_mutex, I_MUTEX_CHILD);
return NULL;
}
void unlock_rename(struct dentry *p1, struct dentry *p2)
{
- up(&p1->d_inode->i_sem);
+ mutex_unlock(&p1->d_inode->i_mutex);
if (p1 != p2) {
- up(&p2->d_inode->i_sem);
- up(&p1->d_inode->i_sb->s_vfs_rename_sem);
+ mutex_unlock(&p2->d_inode->i_mutex);
+ mutex_unlock(&p1->d_inode->i_sb->s_vfs_rename_mutex);
}
}
return error;
DQUOT_INIT(dir);
error = dir->i_op->create(dir, dentry, mode, nd);
- if (!error) {
- inode_dir_notify(dir, DN_CREATE);
- security_inode_post_create(dir, dentry, mode);
- }
+ if (!error)
+ fsnotify_create(dir, dentry);
return error;
}
if (S_ISDIR(inode->i_mode) && (flag & FMODE_WRITE))
return -EISDIR;
- error = permission(inode, acc_mode, nd);
+#ifdef CONFIG_VSERVER_COWBL
+ if (IS_COW(inode) && (flag & FMODE_WRITE)) {
+ if (IS_COW_LINK(inode))
+ return -EMLINK;
+ inode->i_flags &= ~(S_IUNLINK|S_IMMUTABLE);
+ mark_inode_dirty(inode);
+ }
+#endif
+ error = vfs_permission(nd, acc_mode);
if (error)
return error;
return -EACCES;
flag &= ~O_TRUNC;
- } else if ((IS_RDONLY(inode) || (nd && MNT_IS_RDONLY(nd->mnt)))
+ } else if ((IS_RDONLY(inode) || MNT_IS_RDONLY(nd->mnt))
&& (flag & FMODE_WRITE))
return -EROFS;
/*
if (!error) {
DQUOT_INIT(inode);
- error = do_truncate(dentry, 0);
+ error = do_truncate(dentry, 0, ATTR_MTIME|ATTR_CTIME, NULL);
}
put_write_access(inode);
if (error)
return 0;
}
+static int open_namei_create(struct nameidata *nd, struct path *path,
+ int flag, int mode)
+{
+ int error;
+ struct dentry *dir = nd->dentry;
+
+ if (!IS_POSIXACL(dir->d_inode))
+ mode &= ~current->fs->umask;
+ error = vfs_create(dir->d_inode, path->dentry, mode, nd);
+ mutex_unlock(&dir->d_inode->i_mutex);
+ dput(nd->dentry);
+ nd->dentry = path->dentry;
+ if (error)
+ return error;
+ /* Don't check for write permission, don't truncate */
+ return may_open(nd, 0, flag & ~O_TRUNC);
+}
+
/*
* open_namei()
*
* for symlinks (where the permissions are checked later).
* SMP-safe
*/
-int open_namei(const char * pathname, int flag, int mode, struct nameidata *nd)
+int open_namei(int dfd, const char *pathname, int flag,
+ int mode, struct nameidata *nd)
{
- int acc_mode, error = 0;
- struct dentry *dentry;
+ int acc_mode, error;
+ struct path path;
struct dentry *dir;
int count = 0;
+#ifdef CONFIG_VSERVER_COWBL
+ int rflag = flag;
+ int rmode = mode;
+restart:
+#endif
acc_mode = ACC_MODE(flag);
+ /* O_TRUNC implies we need access checks for write permissions */
+ if (flag & O_TRUNC)
+ acc_mode |= MAY_WRITE;
+
/* Allow the LSM permission hook to distinguish append
access from general write access. */
if (flag & O_APPEND)
acc_mode |= MAY_APPEND;
- /* Fill in the open() intent data */
- nd->intent.open.flags = flag;
- nd->intent.open.create_mode = mode;
-
/*
* The simplest case - just a plain lookup.
*/
if (!(flag & O_CREAT)) {
- error = path_lookup(pathname, lookup_flags(flag)|LOOKUP_OPEN, nd);
+ error = path_lookup_open(dfd, pathname, lookup_flags(flag),
+ nd, flag);
if (error)
return error;
goto ok;
/*
* Create - we need to know the parent.
*/
- error = path_lookup(pathname, LOOKUP_PARENT|LOOKUP_OPEN|LOOKUP_CREATE, nd);
+ error = path_lookup_create(dfd,pathname,LOOKUP_PARENT,nd,flag,mode);
if (error)
return error;
dir = nd->dentry;
nd->flags &= ~LOOKUP_PARENT;
- down(&dir->d_inode->i_sem);
- dentry = __lookup_hash(&nd->last, nd->dentry, nd);
+ mutex_lock(&dir->d_inode->i_mutex);
+ path.dentry = lookup_hash(nd);
+ path.mnt = nd->mnt;
do_last:
- error = PTR_ERR(dentry);
- if (IS_ERR(dentry)) {
- up(&dir->d_inode->i_sem);
+ error = PTR_ERR(path.dentry);
+ if (IS_ERR(path.dentry)) {
+ mutex_unlock(&dir->d_inode->i_mutex);
goto exit;
}
+ if (IS_ERR(nd->intent.open.file)) {
+ mutex_unlock(&dir->d_inode->i_mutex);
+ error = PTR_ERR(nd->intent.open.file);
+ goto exit_dput;
+ }
+
/* Negative dentry, just create the file */
- if (!dentry->d_inode) {
- if (!IS_POSIXACL(dir->d_inode))
- mode &= ~current->fs->umask;
- error = vfs_create(dir->d_inode, dentry, mode, nd);
- up(&dir->d_inode->i_sem);
- dput(nd->dentry);
- nd->dentry = dentry;
+ if (!path.dentry->d_inode) {
+ error = open_namei_create(nd, &path, flag, mode);
if (error)
goto exit;
- /* Don't check for write permission, don't truncate */
- acc_mode = 0;
- flag &= ~O_TRUNC;
- goto ok;
+ return 0;
}
/*
* It already exists.
*/
- up(&dir->d_inode->i_sem);
+ mutex_unlock(&dir->d_inode->i_mutex);
+ audit_inode_update(path.dentry->d_inode);
error = -EEXIST;
if (flag & O_EXCL)
goto exit_dput;
- if (d_mountpoint(dentry)) {
+ if (__follow_mount(&path)) {
error = -ELOOP;
if (flag & O_NOFOLLOW)
goto exit_dput;
- while (__follow_down(&nd->mnt,&dentry) && d_mountpoint(dentry));
}
+
error = -ENOENT;
- if (!dentry->d_inode)
+ if (!path.dentry->d_inode)
goto exit_dput;
- if (dentry->d_inode->i_op && dentry->d_inode->i_op->follow_link)
+ if (path.dentry->d_inode->i_op && path.dentry->d_inode->i_op->follow_link)
goto do_link;
- dput(nd->dentry);
- nd->dentry = dentry;
+ path_to_nameidata(&path, nd);
error = -EISDIR;
- if (dentry->d_inode && S_ISDIR(dentry->d_inode->i_mode))
+ if (path.dentry->d_inode && S_ISDIR(path.dentry->d_inode->i_mode))
goto exit;
ok:
error = may_open(nd, acc_mode, flag);
+#ifdef CONFIG_VSERVER_COWBL
+ if (error == -EMLINK) {
+ struct dentry *dentry;
+ dentry = cow_break_link(pathname);
+ if (IS_ERR(dentry)) {
+ error = PTR_ERR(dentry);
+ goto exit;
+ }
+ dput(dentry);
+ release_open_intent(nd);
+ path_release(nd);
+ flag = rflag;
+ mode = rmode;
+ goto restart;
+ }
+#endif
if (error)
goto exit;
return 0;
exit_dput:
- dput(dentry);
+ dput_path(&path, nd);
exit:
+ if (!IS_ERR(nd->intent.open.file))
+ release_open_intent(nd);
path_release(nd);
return error;
* are done. Procfs-like symlinks just set LAST_BIND.
*/
nd->flags |= LOOKUP_PARENT;
- error = security_inode_follow_link(dentry, nd);
+ error = security_inode_follow_link(path.dentry, nd);
if (error)
goto exit_dput;
- touch_atime(nd->mnt, dentry);
- nd_set_link(nd, NULL);
- error = dentry->d_inode->i_op->follow_link(dentry, nd);
- if (!error) {
- char *s = nd_get_link(nd);
- if (s)
- error = __vfs_follow_link(nd, s);
- if (dentry->d_inode->i_op->put_link)
- dentry->d_inode->i_op->put_link(dentry, nd);
- }
- dput(dentry);
- if (error)
+ error = __do_follow_link(&path, nd);
+ if (error) {
+ /* Does someone understand code flow here? Or it is only
+ * me so stupid? Anathema to whoever designed this non-sense
+ * with "intent.open".
+ */
+ release_open_intent(nd);
return error;
+ }
nd->flags &= ~LOOKUP_PARENT;
- if (nd->last_type == LAST_BIND) {
- dentry = nd->dentry;
+ if (nd->last_type == LAST_BIND)
goto ok;
- }
error = -EISDIR;
if (nd->last_type != LAST_NORM)
goto exit;
if (nd->last.name[nd->last.len]) {
- putname(nd->last.name);
+ __putname(nd->last.name);
goto exit;
}
error = -ELOOP;
if (count++==32) {
- putname(nd->last.name);
+ __putname(nd->last.name);
goto exit;
}
dir = nd->dentry;
- down(&dir->d_inode->i_sem);
- dentry = __lookup_hash(&nd->last, nd->dentry, nd);
- putname(nd->last.name);
+ mutex_lock(&dir->d_inode->i_mutex);
+ path.dentry = lookup_hash(nd);
+ path.mnt = nd->mnt;
+ __putname(nd->last.name);
goto do_last;
}
*
* Simple function to lookup and return a dentry and create it
* if it doesn't exist. Is SMP-safe.
+ *
+ * Returns with nd->dentry->d_inode->i_mutex locked.
*/
struct dentry *lookup_create(struct nameidata *nd, int is_dir)
{
- struct dentry *dentry;
- int error;
+ struct dentry *dentry = ERR_PTR(-EEXIST);
- down(&nd->dentry->d_inode->i_sem);
- error = -EEXIST;
+ mutex_lock_nested(&nd->dentry->d_inode->i_mutex, I_MUTEX_PARENT);
+ /*
+ * Yucky last component or no last component at all?
+ * (foo/., foo/.., /////)
+ */
if (nd->last_type != LAST_NORM)
- goto out;
+ goto fail;
nd->flags &= ~LOOKUP_PARENT;
- dentry = lookup_hash(&nd->last, nd->dentry);
+ nd->flags |= LOOKUP_CREATE;
+ nd->intent.open.flags = O_EXCL;
+
+ /*
+ * Do the final lookup.
+ */
+ dentry = lookup_hash(nd);
if (IS_ERR(dentry))
- goto ret;
- error = mnt_may_create(nd->mnt, nd->dentry->d_inode, dentry);
- if (error)
goto fail;
- error = -ENOENT;
+
+ /*
+ * Special case - lookup gave negative, but... we had foo/bar/
+ * From the vfs_mknod() POV we just have a negative dentry -
+ * all is fine. Let's be bastards - you had / on the end, you've
+ * been asking for (non-existent) directory. -ENOENT for you.
+ */
if (!is_dir && nd->last.name[nd->last.len] && !dentry->d_inode)
- goto fail;
-ret:
+ goto enoent;
return dentry;
-fail:
+enoent:
dput(dentry);
-out:
- return ERR_PTR(error);
+ dentry = ERR_PTR(-ENOENT);
+fail:
+ return dentry;
}
+EXPORT_SYMBOL_GPL(lookup_create);
-int vfs_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev)
+int vfs_mknod(struct inode *dir, struct dentry *dentry,
+ int mode, dev_t dev, struct nameidata *nd)
{
- int error = may_create(dir, dentry, NULL);
+ int error = may_create(dir, dentry, nd);
if (error)
return error;
DQUOT_INIT(dir);
error = dir->i_op->mknod(dir, dentry, mode, dev);
- if (!error) {
- inode_dir_notify(dir, DN_CREATE);
- security_inode_post_mknod(dir, dentry, mode, dev);
- }
+ if (!error)
+ fsnotify_create(dir, dentry);
return error;
}
-asmlinkage long sys_mknod(const char __user * filename, int mode, unsigned dev)
+asmlinkage long sys_mknodat(int dfd, const char __user *filename, int mode,
+ unsigned dev)
{
int error = 0;
char * tmp;
if (IS_ERR(tmp))
return PTR_ERR(tmp);
- error = path_lookup(tmp, LOOKUP_PARENT, &nd);
+ error = do_path_lookup(dfd, tmp, LOOKUP_PARENT, &nd);
if (error)
goto out;
dentry = lookup_create(&nd, 0);
error = vfs_create(nd.dentry->d_inode,dentry,mode,&nd);
break;
case S_IFCHR: case S_IFBLK:
- error = vfs_mknod(nd.dentry->d_inode,dentry,mode,
- new_decode_dev(dev));
+ error = vfs_mknod(nd.dentry->d_inode, dentry, mode,
+ new_decode_dev(dev), &nd);
break;
case S_IFIFO: case S_IFSOCK:
- error = vfs_mknod(nd.dentry->d_inode,dentry,mode,0);
+ error = vfs_mknod(nd.dentry->d_inode, dentry, mode,
+ 0, &nd);
break;
case S_IFDIR:
error = -EPERM;
}
dput(dentry);
}
- up(&nd.dentry->d_inode->i_sem);
+ mutex_unlock(&nd.dentry->d_inode->i_mutex);
path_release(&nd);
out:
putname(tmp);
return error;
}
-int vfs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
+asmlinkage long sys_mknod(const char __user *filename, int mode, unsigned dev)
{
- int error = may_create(dir, dentry, NULL);
+ return sys_mknodat(AT_FDCWD, filename, mode, dev);
+}
+
+int vfs_mkdir(struct inode *dir, struct dentry *dentry,
+ int mode, struct nameidata *nd)
+{
+ int error = may_create(dir, dentry, nd);
if (error)
return error;
DQUOT_INIT(dir);
error = dir->i_op->mkdir(dir, dentry, mode);
- if (!error) {
- inode_dir_notify(dir, DN_CREATE);
- security_inode_post_mkdir(dir,dentry, mode);
- }
+ if (!error)
+ fsnotify_mkdir(dir, dentry);
return error;
}
-asmlinkage long sys_mkdir(const char __user * pathname, int mode)
+asmlinkage long sys_mkdirat(int dfd, const char __user *pathname, int mode)
{
int error = 0;
char * tmp;
+ struct dentry *dentry;
+ struct nameidata nd;
tmp = getname(pathname);
error = PTR_ERR(tmp);
- if (!IS_ERR(tmp)) {
- struct dentry *dentry;
- struct nameidata nd;
+ if (IS_ERR(tmp))
+ goto out_err;
- error = path_lookup(tmp, LOOKUP_PARENT, &nd);
- if (error)
- goto out;
- dentry = lookup_create(&nd, 1);
- error = PTR_ERR(dentry);
- if (!IS_ERR(dentry)) {
- if (!IS_POSIXACL(nd.dentry->d_inode))
- mode &= ~current->fs->umask;
- error = vfs_mkdir(nd.dentry->d_inode, dentry, mode);
- dput(dentry);
- }
- up(&nd.dentry->d_inode->i_sem);
- path_release(&nd);
-out:
- putname(tmp);
- }
+ error = do_path_lookup(dfd, tmp, LOOKUP_PARENT, &nd);
+ if (error)
+ goto out;
+ dentry = lookup_create(&nd, 1);
+ error = PTR_ERR(dentry);
+ if (IS_ERR(dentry))
+ goto out_unlock;
+ if (!IS_POSIXACL(nd.dentry->d_inode))
+ mode &= ~current->fs->umask;
+ error = vfs_mkdir(nd.dentry->d_inode, dentry, mode, &nd);
+ dput(dentry);
+out_unlock:
+ mutex_unlock(&nd.dentry->d_inode->i_mutex);
+ path_release(&nd);
+out:
+ putname(tmp);
+out_err:
return error;
}
+asmlinkage long sys_mkdir(const char __user *pathname, int mode)
+{
+ return sys_mkdirat(AT_FDCWD, pathname, mode);
+}
+
/*
* We try to drop the dentry early: we should have
* a usage count of 2 if we're the only user of this
* if it cannot handle the case of removing a directory
* that is still in use by something else..
*/
-static void d_unhash(struct dentry *dentry)
+void dentry_unhash(struct dentry *dentry)
{
dget(dentry);
+ shrink_dcache_parent(dentry);
spin_lock(&dcache_lock);
- switch (atomic_read(&dentry->d_count)) {
- default:
- spin_unlock(&dcache_lock);
- shrink_dcache_parent(dentry);
- spin_lock(&dcache_lock);
- if (atomic_read(&dentry->d_count) != 2)
- break;
- case 2:
+ spin_lock(&dentry->d_lock);
+ if (atomic_read(&dentry->d_count) == 2)
__d_drop(dentry);
- }
+ spin_unlock(&dentry->d_lock);
spin_unlock(&dcache_lock);
}
-int vfs_rmdir(struct inode *dir, struct dentry *dentry)
+int vfs_rmdir(struct inode *dir, struct dentry *dentry,
+ struct nameidata *nd)
{
- int error = may_delete(dir, dentry, 1);
+ int error = may_delete(dir, dentry, 1, nd);
if (error)
return error;
DQUOT_INIT(dir);
- down(&dentry->d_inode->i_sem);
- d_unhash(dentry);
+ mutex_lock(&dentry->d_inode->i_mutex);
+ dentry_unhash(dentry);
if (d_mountpoint(dentry))
error = -EBUSY;
else {
dentry->d_inode->i_flags |= S_DEAD;
}
}
- up(&dentry->d_inode->i_sem);
+ mutex_unlock(&dentry->d_inode->i_mutex);
if (!error) {
- inode_dir_notify(dir, DN_DELETE);
d_delete(dentry);
}
dput(dentry);
return error;
}
-asmlinkage long sys_rmdir(const char __user * pathname)
+static long do_rmdir(int dfd, const char __user *pathname)
{
int error = 0;
char * name;
if(IS_ERR(name))
return PTR_ERR(name);
- error = path_lookup(name, LOOKUP_PARENT, &nd);
+ error = do_path_lookup(dfd, name, LOOKUP_PARENT, &nd);
if (error)
goto exit;
error = -EBUSY;
goto exit1;
}
- down(&nd.dentry->d_inode->i_sem);
- dentry = lookup_hash(&nd.last, nd.dentry);
+ mutex_lock_nested(&nd.dentry->d_inode->i_mutex, I_MUTEX_PARENT);
+ dentry = lookup_hash(&nd);
error = PTR_ERR(dentry);
- if (!IS_ERR(dentry)) {
- error = mnt_may_unlink(nd.mnt, nd.dentry->d_inode, dentry);
- if (error)
- goto exit2;
- error = vfs_rmdir(nd.dentry->d_inode, dentry);
- exit2:
- dput(dentry);
- }
- up(&nd.dentry->d_inode->i_sem);
+ if (IS_ERR(dentry))
+ goto exit2;
+ error = vfs_rmdir(nd.dentry->d_inode, dentry, &nd);
+ dput(dentry);
+exit2:
+ mutex_unlock(&nd.dentry->d_inode->i_mutex);
exit1:
path_release(&nd);
exit:
return error;
}
-int vfs_unlink(struct inode *dir, struct dentry *dentry)
+asmlinkage long sys_rmdir(const char __user *pathname)
+{
+ return do_rmdir(AT_FDCWD, pathname);
+}
+
+int vfs_unlink(struct inode *dir, struct dentry *dentry,
+ struct nameidata *nd)
{
- int error = may_delete(dir, dentry, 0);
+ int error = may_delete(dir, dentry, 0, nd);
if (error)
return error;
DQUOT_INIT(dir);
- down(&dentry->d_inode->i_sem);
+ mutex_lock(&dentry->d_inode->i_mutex);
if (d_mountpoint(dentry))
error = -EBUSY;
else {
if (!error)
error = dir->i_op->unlink(dir, dentry);
}
- up(&dentry->d_inode->i_sem);
+ mutex_unlock(&dentry->d_inode->i_mutex);
/* We don't d_delete() NFS sillyrenamed files--they still exist. */
if (!error && !(dentry->d_flags & DCACHE_NFSFS_RENAMED)) {
d_delete(dentry);
- inode_dir_notify(dir, DN_DELETE);
}
+
return error;
}
/*
* Make sure that the actual truncation of the file will occur outside its
- * directory's i_sem. Truncate can take a long time if there is a lot of
+ * directory's i_mutex. Truncate can take a long time if there is a lot of
* writeout happening, and we don't want to prevent access to the directory
* while waiting on the I/O.
*/
-asmlinkage long sys_unlink(const char __user * pathname)
+static long do_unlinkat(int dfd, const char __user *pathname)
{
int error = 0;
char * name;
if(IS_ERR(name))
return PTR_ERR(name);
- error = path_lookup(name, LOOKUP_PARENT, &nd);
+ error = do_path_lookup(dfd, name, LOOKUP_PARENT, &nd);
if (error)
goto exit;
error = -EISDIR;
if (nd.last_type != LAST_NORM)
goto exit1;
- down(&nd.dentry->d_inode->i_sem);
- dentry = lookup_hash(&nd.last, nd.dentry);
+ mutex_lock_nested(&nd.dentry->d_inode->i_mutex, I_MUTEX_PARENT);
+ dentry = lookup_hash(&nd);
error = PTR_ERR(dentry);
if (!IS_ERR(dentry)) {
/* Why not before? Because we want correct error value */
if (nd.last.name[nd.last.len])
goto slashes;
- error = mnt_may_unlink(nd.mnt, nd.dentry->d_inode, dentry);
- if (error)
- goto exit2;
inode = dentry->d_inode;
if (inode)
atomic_inc(&inode->i_count);
- error = vfs_unlink(nd.dentry->d_inode, dentry);
+ error = vfs_unlink(nd.dentry->d_inode, dentry, &nd);
exit2:
dput(dentry);
}
- up(&nd.dentry->d_inode->i_sem);
+ mutex_unlock(&nd.dentry->d_inode->i_mutex);
+ if (inode)
+ iput(inode); /* truncate the inode here */
exit1:
path_release(&nd);
exit:
putname(name);
-
- if (inode)
- iput(inode); /* truncate the inode here */
return error;
slashes:
goto exit2;
}
-int vfs_symlink(struct inode *dir, struct dentry *dentry, const char *oldname, int mode)
+asmlinkage long sys_unlinkat(int dfd, const char __user *pathname, int flag)
{
- int error = may_create(dir, dentry, NULL);
+ if ((flag & ~AT_REMOVEDIR) != 0)
+ return -EINVAL;
+
+ if (flag & AT_REMOVEDIR)
+ return do_rmdir(dfd, pathname);
+
+ return do_unlinkat(dfd, pathname);
+}
+
+asmlinkage long sys_unlink(const char __user *pathname)
+{
+ return do_unlinkat(AT_FDCWD, pathname);
+}
+
+int vfs_symlink(struct inode *dir, struct dentry *dentry,
+ const char *oldname, int mode, struct nameidata *nd)
+{
+ int error = may_create(dir, dentry, nd);
if (error)
return error;
DQUOT_INIT(dir);
error = dir->i_op->symlink(dir, dentry, oldname);
- if (!error) {
- inode_dir_notify(dir, DN_CREATE);
- security_inode_post_symlink(dir, dentry, oldname);
- }
+ if (!error)
+ fsnotify_create(dir, dentry);
return error;
}
-asmlinkage long sys_symlink(const char __user * oldname, const char __user * newname)
+asmlinkage long sys_symlinkat(const char __user *oldname,
+ int newdfd, const char __user *newname)
{
int error = 0;
char * from;
char * to;
+ struct dentry *dentry;
+ struct nameidata nd;
from = getname(oldname);
if(IS_ERR(from))
return PTR_ERR(from);
to = getname(newname);
error = PTR_ERR(to);
- if (!IS_ERR(to)) {
- struct dentry *dentry;
- struct nameidata nd;
+ if (IS_ERR(to))
+ goto out_putname;
- error = path_lookup(to, LOOKUP_PARENT, &nd);
- if (error)
- goto out;
- dentry = lookup_create(&nd, 0);
- error = PTR_ERR(dentry);
- if (!IS_ERR(dentry)) {
- error = vfs_symlink(nd.dentry->d_inode, dentry, from, S_IALLUGO);
- dput(dentry);
- }
- up(&nd.dentry->d_inode->i_sem);
- path_release(&nd);
+ error = do_path_lookup(newdfd, to, LOOKUP_PARENT, &nd);
+ if (error)
+ goto out;
+ dentry = lookup_create(&nd, 0);
+ error = PTR_ERR(dentry);
+ if (IS_ERR(dentry))
+ goto out_unlock;
+
+ error = vfs_symlink(nd.dentry->d_inode, dentry, from, S_IALLUGO, &nd);
+ dput(dentry);
+out_unlock:
+ mutex_unlock(&nd.dentry->d_inode->i_mutex);
+ path_release(&nd);
out:
- putname(to);
- }
+ putname(to);
+out_putname:
putname(from);
return error;
}
-int vfs_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
+asmlinkage long sys_symlink(const char __user *oldname, const char __user *newname)
+{
+ return sys_symlinkat(oldname, AT_FDCWD, newname);
+}
+
+int vfs_link(struct dentry *old_dentry, struct inode *dir,
+ struct dentry *new_dentry, struct nameidata *nd)
{
struct inode *inode = old_dentry->d_inode;
int error;
if (!inode)
return -ENOENT;
- error = may_create(dir, new_dentry, NULL);
+ error = may_create(dir, new_dentry, nd);
if (error)
return error;
if (error)
return error;
- down(&old_dentry->d_inode->i_sem);
+ mutex_lock(&old_dentry->d_inode->i_mutex);
DQUOT_INIT(dir);
error = dir->i_op->link(old_dentry, dir, new_dentry);
- up(&old_dentry->d_inode->i_sem);
- if (!error) {
- inode_dir_notify(dir, DN_CREATE);
- security_inode_post_link(old_dentry, dir, new_dentry);
- }
+ mutex_unlock(&old_dentry->d_inode->i_mutex);
+ if (!error)
+ fsnotify_create(dir, new_dentry);
return error;
}
* with linux 2.0, and to avoid hard-linking to directories
* and other special files. --ADM
*/
-asmlinkage long sys_link(const char __user * oldname, const char __user * newname)
+asmlinkage long sys_linkat(int olddfd, const char __user *oldname,
+ int newdfd, const char __user *newname,
+ int flags)
{
struct dentry *new_dentry;
struct nameidata nd, old_nd;
int error;
char * to;
+ if ((flags & ~AT_SYMLINK_FOLLOW) != 0)
+ return -EINVAL;
+
to = getname(newname);
if (IS_ERR(to))
return PTR_ERR(to);
- error = __user_walk(oldname, 0, &old_nd);
+ error = __user_walk_fd(olddfd, oldname,
+ flags & AT_SYMLINK_FOLLOW ? LOOKUP_FOLLOW : 0,
+ &old_nd);
if (error)
goto exit;
- error = path_lookup(to, LOOKUP_PARENT, &nd);
+ error = do_path_lookup(newdfd, to, LOOKUP_PARENT, &nd);
if (error)
goto out;
/*
goto out_release;
new_dentry = lookup_create(&nd, 0);
error = PTR_ERR(new_dentry);
- if (!IS_ERR(new_dentry)) {
- error = vfs_link(old_nd.dentry, nd.dentry->d_inode, new_dentry);
- dput(new_dentry);
- }
- up(&nd.dentry->d_inode->i_sem);
+ if (IS_ERR(new_dentry))
+ goto out_unlock;
+ error = vfs_link(old_nd.dentry, nd.dentry->d_inode, new_dentry, &nd);
+ dput(new_dentry);
+out_unlock:
+ mutex_unlock(&nd.dentry->d_inode->i_mutex);
out_release:
path_release(&nd);
out:
return error;
}
+asmlinkage long sys_link(const char __user *oldname, const char __user *newname)
+{
+ return sys_linkat(AT_FDCWD, oldname, AT_FDCWD, newname, 0);
+}
+
/*
* The worst of all namespace operations - renaming directory. "Perverted"
* doesn't even start to describe it. Somebody in UCB had a heck of a trip...
* a) we can get into loop creation. Check is done in is_subdir().
* b) race potential - two innocent renames can create a loop together.
* That's where 4.4 screws up. Current fix: serialization on
- * sb->s_vfs_rename_sem. We might be more accurate, but that's another
+ * sb->s_vfs_rename_mutex. We might be more accurate, but that's another
* story.
* c) we have to lock _three_ objects - parents and victim (if it exists).
- * And that - after we got ->i_sem on parents (until then we don't know
+ * And that - after we got ->i_mutex on parents (until then we don't know
* whether the target exists). Solution: try to be smart with locking
* order for inodes. We rely on the fact that tree topology may change
- * only under ->s_vfs_rename_sem _and_ that parent of the object we
+ * only under ->s_vfs_rename_mutex _and_ that parent of the object we
* move will be locked. Thus we can rank directories by the tree
* (ancestors first) and rank all non-directories after them.
* That works since everybody except rename does "lock parent, lookup,
- * lock child" and rename is under ->s_vfs_rename_sem.
+ * lock child" and rename is under ->s_vfs_rename_mutex.
* HOWEVER, it relies on the assumption that any object with ->lookup()
* has no more than 1 dentry. If "hybrid" objects will ever appear,
* we'd better make sure that there's no link(2) for them.
* stuff into VFS), but the former is not going away. Solution: the same
* trick as in rmdir().
* e) conversion from fhandle to dentry may come in the wrong moment - when
- * we are removing the target. Solution: we will have to grab ->i_sem
+ * we are removing the target. Solution: we will have to grab ->i_mutex
* in the fhandle_to_dentry code. [FIXME - current nfsfh.c relies on
- * ->i_sem on parents, which works but leads to some truely excessive
+ * ->i_mutex on parents, which works but leads to some truely excessive
* locking].
*/
-int vfs_rename_dir(struct inode *old_dir, struct dentry *old_dentry,
- struct inode *new_dir, struct dentry *new_dentry)
+static int vfs_rename_dir(struct inode *old_dir, struct dentry *old_dentry,
+ struct inode *new_dir, struct dentry *new_dentry)
{
int error = 0;
struct inode *target;
target = new_dentry->d_inode;
if (target) {
- down(&target->i_sem);
- d_unhash(new_dentry);
+ mutex_lock(&target->i_mutex);
+ dentry_unhash(new_dentry);
}
if (d_mountpoint(old_dentry)||d_mountpoint(new_dentry))
error = -EBUSY;
if (target) {
if (!error)
target->i_flags |= S_DEAD;
- up(&target->i_sem);
+ mutex_unlock(&target->i_mutex);
if (d_unhashed(new_dentry))
d_rehash(new_dentry);
dput(new_dentry);
}
- if (!error) {
- d_move(old_dentry,new_dentry);
- security_inode_post_rename(old_dir, old_dentry,
- new_dir, new_dentry);
- }
+ if (!error)
+ if (!(old_dir->i_sb->s_type->fs_flags & FS_RENAME_DOES_D_MOVE))
+ d_move(old_dentry,new_dentry);
return error;
}
-int vfs_rename_other(struct inode *old_dir, struct dentry *old_dentry,
- struct inode *new_dir, struct dentry *new_dentry)
+static int vfs_rename_other(struct inode *old_dir, struct dentry *old_dentry,
+ struct inode *new_dir, struct dentry *new_dentry)
{
struct inode *target;
int error;
dget(new_dentry);
target = new_dentry->d_inode;
if (target)
- down(&target->i_sem);
+ mutex_lock(&target->i_mutex);
if (d_mountpoint(old_dentry)||d_mountpoint(new_dentry))
error = -EBUSY;
else
error = old_dir->i_op->rename(old_dir, old_dentry, new_dir, new_dentry);
if (!error) {
- /* The following d_move() should become unconditional */
- if (!(old_dir->i_sb->s_type->fs_flags & FS_ODD_RENAME))
+ if (!(old_dir->i_sb->s_type->fs_flags & FS_RENAME_DOES_D_MOVE))
d_move(old_dentry, new_dentry);
- security_inode_post_rename(old_dir, old_dentry, new_dir, new_dentry);
}
if (target)
- up(&target->i_sem);
+ mutex_unlock(&target->i_mutex);
dput(new_dentry);
return error;
}
{
int error;
int is_dir = S_ISDIR(old_dentry->d_inode->i_mode);
+ const char *old_name;
if (old_dentry->d_inode == new_dentry->d_inode)
return 0;
- error = may_delete(old_dir, old_dentry, is_dir);
+ error = may_delete(old_dir, old_dentry, is_dir, NULL);
if (error)
return error;
if (!new_dentry->d_inode)
error = may_create(new_dir, new_dentry, NULL);
else
- error = may_delete(new_dir, new_dentry, is_dir);
+ error = may_delete(new_dir, new_dentry, is_dir, NULL);
if (error)
return error;
DQUOT_INIT(old_dir);
DQUOT_INIT(new_dir);
+ old_name = fsnotify_oldname_init(old_dentry->d_name.name);
+
if (is_dir)
error = vfs_rename_dir(old_dir,old_dentry,new_dir,new_dentry);
else
error = vfs_rename_other(old_dir,old_dentry,new_dir,new_dentry);
if (!error) {
- if (old_dir == new_dir)
- inode_dir_notify(old_dir, DN_RENAME);
- else {
- inode_dir_notify(old_dir, DN_DELETE);
- inode_dir_notify(new_dir, DN_CREATE);
- }
+ const char *new_name = old_dentry->d_name.name;
+ fsnotify_move(old_dir, new_dir, old_name, new_name, is_dir,
+ new_dentry->d_inode, old_dentry->d_inode);
}
+ fsnotify_oldname_free(old_name);
+
return error;
}
-static inline int do_rename(const char * oldname, const char * newname)
+static int do_rename(int olddfd, const char *oldname,
+ int newdfd, const char *newname)
{
int error = 0;
struct dentry * old_dir, * new_dir;
struct dentry * trap;
struct nameidata oldnd, newnd;
- error = path_lookup(oldname, LOOKUP_PARENT, &oldnd);
+ error = do_path_lookup(olddfd, oldname, LOOKUP_PARENT, &oldnd);
if (error)
goto exit;
- error = path_lookup(newname, LOOKUP_PARENT, &newnd);
+ error = do_path_lookup(newdfd, newname, LOOKUP_PARENT, &newnd);
if (error)
goto exit1;
trap = lock_rename(new_dir, old_dir);
- old_dentry = lookup_hash(&oldnd.last, old_dir);
+ old_dentry = lookup_hash(&oldnd);
error = PTR_ERR(old_dentry);
if (IS_ERR(old_dentry))
goto exit3;
error = -EROFS;
if (MNT_IS_RDONLY(newnd.mnt))
goto exit4;
- new_dentry = lookup_hash(&newnd.last, new_dir);
+ new_dentry = lookup_hash(&newnd);
error = PTR_ERR(new_dentry);
if (IS_ERR(new_dentry))
goto exit4;
return error;
}
-asmlinkage long sys_rename(const char __user * oldname, const char __user * newname)
+asmlinkage long sys_renameat(int olddfd, const char __user *oldname,
+ int newdfd, const char __user *newname)
{
int error;
char * from;
to = getname(newname);
error = PTR_ERR(to);
if (!IS_ERR(to)) {
- error = do_rename(from,to);
+ error = do_rename(olddfd, from, newdfd, to);
putname(to);
}
putname(from);
return error;
}
+asmlinkage long sys_rename(const char __user *oldname, const char __user *newname)
+{
+ return sys_renameat(AT_FDCWD, oldname, AT_FDCWD, newname);
+}
+
int vfs_readlink(struct dentry *dentry, char __user *buffer, int buflen, const char *link)
{
int len;
int generic_readlink(struct dentry *dentry, char __user *buffer, int buflen)
{
struct nameidata nd;
- int res;
+ void *cookie;
+
nd.depth = 0;
- res = dentry->d_inode->i_op->follow_link(dentry, &nd);
- if (!res) {
- res = vfs_readlink(dentry, buffer, buflen, nd_get_link(&nd));
+ cookie = dentry->d_inode->i_op->follow_link(dentry, &nd);
+ if (!IS_ERR(cookie)) {
+ int res = vfs_readlink(dentry, buffer, buflen, nd_get_link(&nd));
if (dentry->d_inode->i_op->put_link)
- dentry->d_inode->i_op->put_link(dentry, &nd);
+ dentry->d_inode->i_op->put_link(dentry, &nd, cookie);
+ cookie = ERR_PTR(res);
}
- return res;
+ return PTR_ERR(cookie);
}
int vfs_follow_link(struct nameidata *nd, const char *link)
return __vfs_follow_link(nd, link);
}
+
+#ifdef CONFIG_VSERVER_COWBL
+
+#include <linux/file.h>
+
+struct dentry *cow_break_link(const char *pathname)
+{
+ int ret, mode, pathlen;
+ struct nameidata old_nd, dir_nd;
+ struct dentry *old_dentry, *new_dentry;
+ struct dentry *res = ERR_PTR(-EMLINK);
+ struct vfsmount *old_mnt, *new_mnt;
+ struct file *old_file;
+ struct file *new_file;
+ char *to, *path, pad='\251';
+ loff_t size;
+
+ vxdprintk(VXD_CBIT(misc, 1), "cow_break_link(»%s«)", pathname);
+ path = kmalloc(PATH_MAX, GFP_KERNEL);
+
+ ret = path_lookup(pathname, LOOKUP_FOLLOW, &old_nd);
+ vxdprintk(VXD_CBIT(misc, 2), "path_lookup(old): %d", ret);
+ old_dentry = old_nd.dentry;
+ old_mnt = old_nd.mnt;
+ mode = old_dentry->d_inode->i_mode;
+
+ to = d_path(old_dentry, old_mnt, path, PATH_MAX-2);
+ pathlen = strlen(to);
+ vxdprintk(VXD_CBIT(misc, 2), "old path »%s«", to);
+
+ to[pathlen+1] = 0;
+retry:
+ to[pathlen] = pad--;
+ if (pad <= '\240')
+ goto out_rel_old;
+
+ vxdprintk(VXD_CBIT(misc, 1), "temp copy »%s«", to);
+ ret = path_lookup(to,
+ LOOKUP_PARENT|LOOKUP_OPEN|LOOKUP_CREATE, &dir_nd);
+
+ /* this puppy downs the inode sem */
+ new_dentry = lookup_create(&dir_nd, 0);
+ vxdprintk(VXD_CBIT(misc, 2),
+ "lookup_create(new): %p", new_dentry);
+ if (!new_dentry) {
+ path_release(&dir_nd);
+ goto retry;
+ }
+
+ ret = vfs_create(dir_nd.dentry->d_inode, new_dentry, mode, &dir_nd);
+ vxdprintk(VXD_CBIT(misc, 2),
+ "vfs_create(new): %d", ret);
+ if (ret == -EEXIST) {
+ mutex_unlock(&dir_nd.dentry->d_inode->i_mutex);
+ dput(new_dentry);
+ path_release(&dir_nd);
+ goto retry;
+ }
+ else if (ret < 0) {
+ res = ERR_PTR(ret);
+ goto out_rel_both;
+ }
+
+ new_mnt = dir_nd.mnt;
+
+ dget(old_dentry);
+ mntget(old_mnt);
+ /* this one cleans up the dentry in case of failure */
+ old_file = dentry_open(old_dentry, old_mnt, O_RDONLY);
+ vxdprintk(VXD_CBIT(misc, 2),
+ "dentry_open(old): %p", old_file);
+ if (!old_file)
+ goto out_rel_both;
+
+ dget(new_dentry);
+ mntget(new_mnt);
+ /* this one cleans up the dentry in case of failure */
+ new_file = dentry_open(new_dentry, new_mnt, O_WRONLY);
+ vxdprintk(VXD_CBIT(misc, 2),
+ "dentry_open(new): %p", new_file);
+ if (!new_file)
+ goto out_fput_old;
+
+ size = i_size_read(old_file->f_dentry->d_inode);
+ ret = vfs_sendfile(new_file, old_file, NULL, size, 0);
+ vxdprintk(VXD_CBIT(misc, 2), "vfs_sendfile: %d", ret);
+
+ if (ret < 0)
+ goto out_fput_both;
+
+ ret = vfs_rename(dir_nd.dentry->d_inode, new_dentry,
+ old_nd.dentry->d_parent->d_inode, old_dentry);
+ vxdprintk(VXD_CBIT(misc, 2), "vfs_rename: %d", ret);
+ if (!ret) {
+ res = new_dentry;
+ dget(new_dentry);
+ }
+
+out_fput_both:
+ vxdprintk(VXD_CBIT(misc, 3),
+ "fput(new_file=%p[#%d])", new_file,
+ atomic_read(&new_file->f_count));
+ fput(new_file);
+
+out_fput_old:
+ vxdprintk(VXD_CBIT(misc, 3),
+ "fput(old_file=%p[#%d])", old_file,
+ atomic_read(&old_file->f_count));
+ fput(old_file);
+
+out_rel_both:
+ mutex_unlock(&dir_nd.dentry->d_inode->i_mutex);
+ dput(new_dentry);
+
+ path_release(&dir_nd);
+out_rel_old:
+ path_release(&old_nd);
+ kfree(path);
+ return res;
+}
+
+#endif
+
/* get the link contents into pagecache */
static char *page_getlink(struct dentry * dentry, struct page **ppage)
{
struct page * page;
struct address_space *mapping = dentry->d_inode->i_mapping;
- page = read_cache_page(mapping, 0, (filler_t *)mapping->a_ops->readpage,
- NULL);
+ page = read_mapping_page(mapping, 0, NULL);
if (IS_ERR(page))
goto sync_fail;
wait_on_page_locked(page);
return res;
}
-int page_follow_link_light(struct dentry *dentry, struct nameidata *nd)
+void *page_follow_link_light(struct dentry *dentry, struct nameidata *nd)
{
- struct page *page;
+ struct page *page = NULL;
nd_set_link(nd, page_getlink(dentry, &page));
- return 0;
+ return page;
}
-void page_put_link(struct dentry *dentry, struct nameidata *nd)
+void page_put_link(struct dentry *dentry, struct nameidata *nd, void *cookie)
{
- if (!IS_ERR(nd_get_link(nd))) {
- struct page *page;
- page = find_get_page(dentry->d_inode->i_mapping, 0);
- if (!page)
- BUG();
- kunmap(page);
- page_cache_release(page);
- page_cache_release(page);
- }
-}
+ struct page *page = cookie;
-int page_follow_link(struct dentry *dentry, struct nameidata *nd)
-{
- struct page *page = NULL;
- char *s = page_getlink(dentry, &page);
- int res = __vfs_follow_link(nd, s);
if (page) {
kunmap(page);
page_cache_release(page);
}
- return res;
}
-int page_symlink(struct inode *inode, const char *symname, int len)
+int __page_symlink(struct inode *inode, const char *symname, int len,
+ gfp_t gfp_mask)
{
struct address_space *mapping = inode->i_mapping;
- struct page *page = grab_cache_page(mapping, 0);
+ struct page *page;
int err = -ENOMEM;
char *kaddr;
+retry:
+ page = find_or_create_page(mapping, 0, gfp_mask);
if (!page)
goto fail;
err = mapping->a_ops->prepare_write(NULL, page, 0, len-1);
+ if (err == AOP_TRUNCATED_PAGE) {
+ page_cache_release(page);
+ goto retry;
+ }
if (err)
goto fail_map;
kaddr = kmap_atomic(page, KM_USER0);
memcpy(kaddr, symname, len-1);
kunmap_atomic(kaddr, KM_USER0);
- mapping->a_ops->commit_write(NULL, page, 0, len-1);
+ err = mapping->a_ops->commit_write(NULL, page, 0, len-1);
+ if (err == AOP_TRUNCATED_PAGE) {
+ page_cache_release(page);
+ goto retry;
+ }
+ if (err)
+ goto fail_map;
/*
* Notice that we are _not_ going to block here - end of page is
* unmapped, so this will only try to map the rest of page, see
*/
if (!PageUptodate(page)) {
err = mapping->a_ops->readpage(NULL, page);
- wait_on_page_locked(page);
+ if (err != AOP_TRUNCATED_PAGE)
+ wait_on_page_locked(page);
} else {
unlock_page(page);
}
return err;
}
+int page_symlink(struct inode *inode, const char *symname, int len)
+{
+ return __page_symlink(inode, symname, len,
+ mapping_gfp_mask(inode->i_mapping));
+}
+
struct inode_operations page_symlink_inode_operations = {
.readlink = generic_readlink,
.follow_link = page_follow_link_light,
};
EXPORT_SYMBOL(__user_walk);
+EXPORT_SYMBOL(__user_walk_fd);
EXPORT_SYMBOL(follow_down);
EXPORT_SYMBOL(follow_up);
EXPORT_SYMBOL(get_write_access); /* binfmt_aout */
EXPORT_SYMBOL(getname);
EXPORT_SYMBOL(lock_rename);
-EXPORT_SYMBOL(lookup_create);
-EXPORT_SYMBOL(lookup_hash);
EXPORT_SYMBOL(lookup_one_len);
-EXPORT_SYMBOL(page_follow_link);
EXPORT_SYMBOL(page_follow_link_light);
EXPORT_SYMBOL(page_put_link);
EXPORT_SYMBOL(page_readlink);
+EXPORT_SYMBOL(__page_symlink);
EXPORT_SYMBOL(page_symlink);
EXPORT_SYMBOL(page_symlink_inode_operations);
EXPORT_SYMBOL(path_lookup);
EXPORT_SYMBOL(path_release);
EXPORT_SYMBOL(path_walk);
EXPORT_SYMBOL(permission);
+EXPORT_SYMBOL(vfs_permission);
+EXPORT_SYMBOL(file_permission);
EXPORT_SYMBOL(unlock_rename);
EXPORT_SYMBOL(vfs_create);
EXPORT_SYMBOL(vfs_follow_link);
EXPORT_SYMBOL(vfs_link);
EXPORT_SYMBOL(vfs_mkdir);
EXPORT_SYMBOL(vfs_mknod);
-EXPORT_SYMBOL(vfs_permission);
+EXPORT_SYMBOL(generic_permission);
EXPORT_SYMBOL(vfs_readlink);
EXPORT_SYMBOL(vfs_rename);
EXPORT_SYMBOL(vfs_rmdir);
EXPORT_SYMBOL(vfs_symlink);
EXPORT_SYMBOL(vfs_unlink);
+EXPORT_SYMBOL(dentry_unhash);
EXPORT_SYMBOL(generic_readlink);