]> nv-tegra.nvidia Code Review - linux-2.6.git/blobdiff - fs/namei.c
Untangling ima mess, part 2: deal with counters
[linux-2.6.git] / fs / namei.c
index 3b67be7631dc21b4d76bb4e2ee45b486eb0bb720..c530e5d32f1282971415749b45fc3a816c16a7c2 100644 (file)
@@ -24,6 +24,7 @@
 #include <linux/fsnotify.h>
 #include <linux/personality.h>
 #include <linux/security.h>
+#include <linux/ima.h>
 #include <linux/syscalls.h>
 #include <linux/mount.h>
 #include <linux/audit.h>
 #include <linux/file.h>
 #include <linux/fcntl.h>
 #include <linux/device_cgroup.h>
-#include <asm/namei.h>
+#include <linux/fs_struct.h>
 #include <asm/uaccess.h>
 
+#include "internal.h"
+
 #define ACC_MODE(x) ("\000\004\002\006"[(x)&O_ACCMODE])
 
 /* [Feb-1997 T. Schoebel-Theuer]
  * any extra contention...
  */
 
-static int __link_path_walk(const char *name, struct nameidata *nd);
-
 /* In order to reduce some races, while at the same time doing additional
  * checking and hopefully speeding things up, we copy filenames to the
  * kernel data space before using them..
@@ -168,33 +169,22 @@ void putname(const char *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
- *
- * 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..
+/*
+ * This does basic POSIX ACL permission checking
  */
-int generic_permission(struct inode *inode, int mask,
+static int acl_permission_check(struct inode *inode, int mask,
                int (*check_acl)(struct inode *inode, int mask))
 {
        umode_t                 mode = inode->i_mode;
 
        mask &= MAY_READ | MAY_WRITE | MAY_EXEC;
 
-       if (current->fsuid == inode->i_uid)
+       if (current_fsuid() == inode->i_uid)
                mode >>= 6;
        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)
+                       if (error != -EAGAIN)
                                return error;
                }
 
@@ -207,14 +197,37 @@ int generic_permission(struct inode *inode, int mask,
         */
        if ((mask & ~mode) == 0)
                return 0;
+       return -EACCES;
+}
+
+/**
+ * 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
+ *
+ * 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 generic_permission(struct inode *inode, int mask,
+               int (*check_acl)(struct inode *inode, int mask))
+{
+       int ret;
+
+       /*
+        * Do the basic POSIX ACL permission checks.
+        */
+       ret = acl_permission_check(inode, mask, check_acl);
+       if (ret != -EACCES)
+               return ret;
 
- check_capabilities:
        /*
         * Read/write DACs are always overridable.
         * Executable DACs are overridable if at least one exec bit is set.
         */
-       if (!(mask & MAY_EXEC) ||
-           (inode->i_mode & S_IXUGO) || S_ISDIR(inode->i_mode))
+       if (!(mask & MAY_EXEC) || execute_ok(inode))
                if (capable(CAP_DAC_OVERRIDE))
                        return 0;
 
@@ -228,13 +241,19 @@ int generic_permission(struct inode *inode, int mask,
        return -EACCES;
 }
 
-int permission(struct inode *inode, int mask, struct nameidata *nd)
+/**
+ * inode_permission  -  check for access rights to a given inode
+ * @inode:     inode to check permission on
+ * @mask:      right to check for (%MAY_READ, %MAY_WRITE, %MAY_EXEC)
+ *
+ * Used to check for read/write/execute permissions on an inode.
+ * 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 inode_permission(struct inode *inode, int mask)
 {
        int retval;
-       struct vfsmount *mnt = NULL;
-
-       if (nd)
-               mnt = nd->path.mnt;
 
        if (mask & MAY_WRITE) {
                umode_t mode = inode->i_mode;
@@ -253,42 +272,11 @@ int permission(struct inode *inode, int mask, struct nameidata *nd)
                        return -EACCES;
        }
 
-       if ((mask & MAY_EXEC) && S_ISREG(inode->i_mode)) {
-               /*
-                * MAY_EXEC on regular files is denied if the fs is mounted
-                * with the "noexec" flag.
-                */
-               if (mnt && (mnt->mnt_flags & MNT_NOEXEC))
-                       return -EACCES;
-       }
+       if (inode->i_op->permission)
+               retval = inode->i_op->permission(inode, mask);
+       else
+               retval = generic_permission(inode, mask, inode->i_op->check_acl);
 
-       /* Ordinary permission routines do not understand MAY_APPEND. */
-       if (inode->i_op && inode->i_op->permission) {
-               int extra = 0;
-               if (nd) {
-                       if (nd->flags & LOOKUP_ACCESS)
-                               extra |= MAY_ACCESS;
-                       if (nd->flags & LOOKUP_CHDIR)
-                               extra |= MAY_CHDIR;
-                       if (nd->flags & LOOKUP_OPEN)
-                               extra |= MAY_OPEN;
-               }
-               retval = inode->i_op->permission(inode, mask | extra);
-               if (!retval) {
-                       /*
-                        * Exec permission on a regular file is denied if none
-                        * of the execute bits are set.
-                        *
-                        * This check should be done by the ->permission()
-                        * method.
-                        */
-                       if ((mask & MAY_EXEC) && S_ISREG(inode->i_mode) &&
-                           !(inode->i_mode & S_IXUGO))
-                               return -EACCES;
-               }
-       } else {
-               retval = generic_permission(inode, mask, NULL);
-       }
        if (retval)
                return retval;
 
@@ -297,22 +285,7 @@ int permission(struct inode *inode, int mask, struct nameidata *nd)
                return retval;
 
        return security_inode_permission(inode,
-                       mask & (MAY_READ|MAY_WRITE|MAY_EXEC), 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->path.dentry->d_inode, mask, nd);
+                       mask & (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND));
 }
 
 /**
@@ -325,11 +298,11 @@ int vfs_permission(struct nameidata *nd, int mask)
  *
  * Note:
  *     Do not use this function in new code.  All access checks should
- *     be done using vfs_permission().
+ *     be done using inode_permission().
  */
 int file_permission(struct file *file, int mask)
 {
-       return permission(file->f_path.dentry->d_inode, mask, NULL);
+       return inode_permission(file->f_path.dentry->d_inode, mask);
 }
 
 /*
@@ -441,180 +414,48 @@ do_revalidate(struct dentry *dentry, struct nameidata *nd)
 }
 
 /*
- * Internal lookup() using the new generic dcache.
- * SMP-safe
- */
-static struct dentry * cached_lookup(struct dentry * parent, struct qstr * name, struct nameidata *nd)
-{
-       struct dentry * dentry = __d_lookup(parent, name);
-
-       /* lockess __d_lookup may fail due to concurrent d_move() 
-        * in some unrelated directory, so try with d_lookup
-        */
-       if (!dentry)
-               dentry = d_lookup(parent, name);
-
-       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 generic_permission(), and tests ONLY for
- * MAY_EXEC permission.
+ * Short-cut version of permission(), for calling on directories
+ * during pathname resolution.  Combines parts 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
+ * short-cut DAC fails, then call ->permission() to do more
  * complete permission check.
  */
-static int exec_permission_lite(struct inode *inode,
-                                      struct nameidata *nd)
+static int exec_permission(struct inode *inode)
 {
-       umode_t mode = inode->i_mode;
-
-       if (inode->i_op && inode->i_op->permission)
-               return -EAGAIN;
-
-       if (current->fsuid == inode->i_uid)
-               mode >>= 6;
-       else if (in_group_p(inode->i_gid))
-               mode >>= 3;
-
-       if (mode & MAY_EXEC)
-               goto ok;
-
-       if ((inode->i_mode & S_IXUGO) && capable(CAP_DAC_OVERRIDE))
-               goto ok;
+       int ret;
 
-       if (S_ISDIR(inode->i_mode) && capable(CAP_DAC_OVERRIDE))
+       if (inode->i_op->permission) {
+               ret = inode->i_op->permission(inode, MAY_EXEC);
+               if (!ret)
+                       goto ok;
+               return ret;
+       }
+       ret = acl_permission_check(inode, MAY_EXEC, inode->i_op->check_acl);
+       if (!ret)
                goto ok;
 
-       if (S_ISDIR(inode->i_mode) && capable(CAP_DAC_READ_SEARCH))
+       if (capable(CAP_DAC_OVERRIDE) || capable(CAP_DAC_READ_SEARCH))
                goto ok;
 
-       return -EACCES;
+       return ret;
 ok:
-       return security_inode_permission(inode, MAY_EXEC, nd);
+       return security_inode_permission(inode, MAY_EXEC);
 }
 
-/*
- * This is called when everything else fails, and we actually have
- * to go to the low-level filesystem to find out what we should do..
- *
- * We get the directory semaphore, and after getting that we also
- * make sure that nobody added the entry to the dcache in the meantime..
- * SMP-safe
- */
-static struct dentry * real_lookup(struct dentry * parent, struct qstr * name, struct nameidata *nd)
+static __always_inline void set_root(struct nameidata *nd)
 {
-       struct dentry * result;
-       struct inode *dir = parent->d_inode;
-
-       mutex_lock(&dir->i_mutex);
-       /*
-        * First re-do the cached lookup just in case it was created
-        * while we waited for the directory semaphore..
-        *
-        * FIXME! This could use version numbering or similar to
-        * avoid unnecessary cache lookups.
-        *
-        * The "dcache_lock" is purely to protect the RCU list walker
-        * from concurrent renames at this point (we mustn't get false
-        * negatives from the RCU list walk here, unlike the optimistic
-        * fast walk).
-        *
-        * so doing d_lookup() (with seqlock), instead of lockfree __d_lookup
-        */
-       result = d_lookup(parent, name);
-       if (!result) {
-               struct dentry *dentry;
-
-               /* Don't create child dentry for a dead directory. */
-               result = ERR_PTR(-ENOENT);
-               if (IS_DEADDIR(dir))
-                       goto out_unlock;
-
-               dentry = d_alloc(parent, name);
-               result = ERR_PTR(-ENOMEM);
-               if (dentry) {
-                       result = dir->i_op->lookup(dir, dentry, nd);
-                       if (result)
-                               dput(dentry);
-                       else
-                               result = dentry;
-               }
-out_unlock:
-               mutex_unlock(&dir->i_mutex);
-               return result;
-       }
-
-       /*
-        * Uhhuh! Nasty case: the cache was re-populated while
-        * we waited on the semaphore. Need to revalidate.
-        */
-       mutex_unlock(&dir->i_mutex);
-       if (result->d_op && result->d_op->d_revalidate) {
-               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 __always_inline int
-walk_init_root(const char *name, struct nameidata *nd)
-{
-       struct fs_struct *fs = current->fs;
-
-       read_lock(&fs->lock);
-       if (fs->altroot.dentry && !(nd->flags & LOOKUP_NOALT)) {
-               nd->path = fs->altroot;
-               path_get(&fs->altroot);
-               read_unlock(&fs->lock);
-               if (__emul_lookup_dentry(name,nd))
-                       return 0;
+       if (!nd->root.mnt) {
+               struct fs_struct *fs = current->fs;
                read_lock(&fs->lock);
+               nd->root = fs->root;
+               path_get(&nd->root);
+               read_unlock(&fs->lock);
        }
-       nd->path = fs->root;
-       path_get(&fs->root);
-       read_unlock(&fs->lock);
-       return 1;
 }
 
-/*
- * 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.
- */
-static __always_inline int link_path_walk(const char *name, struct nameidata *nd)
-{
-       struct path save = nd->path;
-       int result;
-
-       /* make sure the stuff we saved doesn't go away */
-       path_get(&save);
-
-       result = __link_path_walk(name, nd);
-       if (result == -ESTALE) {
-               /* nd->path had been dropped */
-               nd->path = save;
-               path_get(&nd->path);
-               nd->flags |= LOOKUP_REVAL;
-               result = __link_path_walk(name, nd);
-       }
-
-       path_put(&save);
-
-       return result;
-}
+static int link_path_walk(const char *, struct nameidata *);
 
 static __always_inline int __vfs_follow_link(struct nameidata *nd, const char *link)
 {
@@ -624,13 +465,13 @@ static __always_inline int __vfs_follow_link(struct nameidata *nd, const char *l
                goto fail;
 
        if (*link == '/') {
+               set_root(nd);
                path_put(&nd->path);
-               if (!walk_init_root(link, nd))
-                       /* weird __emul_prefix() stuff did it */
-                       goto out;
+               nd->path = nd->root;
+               path_get(&nd->root);
        }
+
        res = link_path_walk(link, nd);
-out:
        if (nd->depth || res || nd->last_type!=LAST_NORM)
                return res;
        /*
@@ -691,8 +532,6 @@ static __always_inline int __do_follow_link(struct path *path, struct nameidata
                if (dentry->d_inode->i_op->put_link)
                        dentry->d_inode->i_op->put_link(dentry, nd, cookie);
        }
-       path_put(path);
-
        return error;
 }
 
@@ -719,6 +558,7 @@ static inline int do_follow_link(struct path *path, struct nameidata *nd)
        current->total_link_count++;
        nd->depth++;
        err = __do_follow_link(path, nd);
+       path_put(path);
        current->link_count--;
        nd->depth--;
        return err;
@@ -728,23 +568,23 @@ loop:
        return err;
 }
 
-int follow_up(struct vfsmount **mnt, struct dentry **dentry)
+int follow_up(struct path *path)
 {
        struct vfsmount *parent;
        struct dentry *mountpoint;
        spin_lock(&vfsmount_lock);
-       parent=(*mnt)->mnt_parent;
-       if (parent == *mnt) {
+       parent = path->mnt->mnt_parent;
+       if (parent == path->mnt) {
                spin_unlock(&vfsmount_lock);
                return 0;
        }
        mntget(parent);
-       mountpoint=dget((*mnt)->mnt_mountpoint);
+       mountpoint = dget(path->mnt->mnt_mountpoint);
        spin_unlock(&vfsmount_lock);
-       dput(*dentry);
-       *dentry = mountpoint;
-       mntput(*mnt);
-       *mnt = parent;
+       dput(path->dentry);
+       path->dentry = mountpoint;
+       mntput(path->mnt);
+       path->mnt = parent;
        return 1;
 }
 
@@ -755,7 +595,7 @@ static int __follow_mount(struct path *path)
 {
        int res = 0;
        while (d_mountpoint(path->dentry)) {
-               struct vfsmount *mounted = lookup_mnt(path->mnt, path->dentry);
+               struct vfsmount *mounted = lookup_mnt(path);
                if (!mounted)
                        break;
                dput(path->dentry);
@@ -768,32 +608,32 @@ static int __follow_mount(struct path *path)
        return res;
 }
 
-static void follow_mount(struct vfsmount **mnt, struct dentry **dentry)
+static void follow_mount(struct path *path)
 {
-       while (d_mountpoint(*dentry)) {
-               struct vfsmount *mounted = lookup_mnt(*mnt, *dentry);
+       while (d_mountpoint(path->dentry)) {
+               struct vfsmount *mounted = lookup_mnt(path);
                if (!mounted)
                        break;
-               dput(*dentry);
-               mntput(*mnt);
-               *mnt = mounted;
-               *dentry = dget(mounted->mnt_root);
+               dput(path->dentry);
+               mntput(path->mnt);
+               path->mnt = mounted;
+               path->dentry = dget(mounted->mnt_root);
        }
 }
 
 /* no need for dcache_lock, as serialization is taken care in
  * namespace.c
  */
-int follow_down(struct vfsmount **mnt, struct dentry **dentry)
+int follow_down(struct path *path)
 {
        struct vfsmount *mounted;
 
-       mounted = lookup_mnt(*mnt, *dentry);
+       mounted = lookup_mnt(path);
        if (mounted) {
-               dput(*dentry);
-               mntput(*mnt);
-               *mnt = mounted;
-               *dentry = dget(mounted->mnt_root);
+               dput(path->dentry);
+               mntput(path->mnt);
+               path->mnt = mounted;
+               path->dentry = dget(mounted->mnt_root);
                return 1;
        }
        return 0;
@@ -801,19 +641,16 @@ int follow_down(struct vfsmount **mnt, struct dentry **dentry)
 
 static __always_inline void follow_dotdot(struct nameidata *nd)
 {
-       struct fs_struct *fs = current->fs;
+       set_root(nd);
 
        while(1) {
                struct vfsmount *parent;
                struct dentry *old = nd->path.dentry;
 
-                read_lock(&fs->lock);
-               if (nd->path.dentry == fs->root.dentry &&
-                   nd->path.mnt == fs->root.mnt) {
-                        read_unlock(&fs->lock);
+               if (nd->path.dentry == nd->root.dentry &&
+                   nd->path.mnt == nd->root.mnt) {
                        break;
                }
-                read_unlock(&fs->lock);
                spin_lock(&dcache_lock);
                if (nd->path.dentry != nd->path.mnt->mnt_root) {
                        nd->path.dentry = dget(nd->path.dentry->d_parent);
@@ -835,7 +672,7 @@ static __always_inline void follow_dotdot(struct nameidata *nd)
                mntput(nd->path.mnt);
                nd->path.mnt = parent;
        }
-       follow_mount(&nd->path.mnt, &nd->path.dentry);
+       follow_mount(&nd->path);
 }
 
 /*
@@ -847,8 +684,19 @@ static int do_lookup(struct nameidata *nd, struct qstr *name,
                     struct path *path)
 {
        struct vfsmount *mnt = nd->path.mnt;
-       struct dentry *dentry = __d_lookup(nd->path.dentry, name);
+       struct dentry *dentry, *parent;
+       struct inode *dir;
+       /*
+        * See if the low-level filesystem might want
+        * to use its own hash..
+        */
+       if (nd->path.dentry->d_op && nd->path.dentry->d_op->d_hash) {
+               int err = nd->path.dentry->d_op->d_hash(nd->path.dentry, name);
+               if (err < 0)
+                       return err;
+       }
 
+       dentry = __d_lookup(nd->path.dentry, name);
        if (!dentry)
                goto need_lookup;
        if (dentry->d_op && dentry->d_op->d_revalidate)
@@ -860,7 +708,59 @@ done:
        return 0;
 
 need_lookup:
-       dentry = real_lookup(nd->path.dentry, name, nd);
+       parent = nd->path.dentry;
+       dir = parent->d_inode;
+
+       mutex_lock(&dir->i_mutex);
+       /*
+        * First re-do the cached lookup just in case it was created
+        * while we waited for the directory semaphore..
+        *
+        * FIXME! This could use version numbering or similar to
+        * avoid unnecessary cache lookups.
+        *
+        * The "dcache_lock" is purely to protect the RCU list walker
+        * from concurrent renames at this point (we mustn't get false
+        * negatives from the RCU list walk here, unlike the optimistic
+        * fast walk).
+        *
+        * so doing d_lookup() (with seqlock), instead of lockfree __d_lookup
+        */
+       dentry = d_lookup(parent, name);
+       if (!dentry) {
+               struct dentry *new;
+
+               /* Don't create child dentry for a dead directory. */
+               dentry = ERR_PTR(-ENOENT);
+               if (IS_DEADDIR(dir))
+                       goto out_unlock;
+
+               new = d_alloc(parent, name);
+               dentry = ERR_PTR(-ENOMEM);
+               if (new) {
+                       dentry = dir->i_op->lookup(dir, new, nd);
+                       if (dentry)
+                               dput(new);
+                       else
+                               dentry = new;
+               }
+out_unlock:
+               mutex_unlock(&dir->i_mutex);
+               if (IS_ERR(dentry))
+                       goto fail;
+               goto done;
+       }
+
+       /*
+        * Uhhuh! Nasty case: the cache was re-populated while
+        * we waited on the semaphore. Need to revalidate.
+        */
+       mutex_unlock(&dir->i_mutex);
+       if (dentry->d_op && dentry->d_op->d_revalidate) {
+               dentry = do_revalidate(dentry, nd);
+               if (!dentry)
+                       dentry = ERR_PTR(-ENOENT);
+       }
        if (IS_ERR(dentry))
                goto fail;
        goto done;
@@ -885,7 +785,7 @@ fail:
  * Returns 0 and nd will have valid dentry and mnt on success.
  * Returns error and drops reference to input namei data on failure.
  */
-static int __link_path_walk(const char *name, struct nameidata *nd)
+static int link_path_walk(const char *name, struct nameidata *nd)
 {
        struct path next;
        struct inode *inode;
@@ -908,9 +808,7 @@ static int __link_path_walk(const char *name, struct nameidata *nd)
                unsigned int c;
 
                nd->flags |= LOOKUP_CONTINUE;
-               err = exec_permission_lite(inode, nd);
-               if (err == -EAGAIN)
-                       err = vfs_permission(nd, MAY_EXEC);
+               err = exec_permission(inode);
                if (err)
                        break;
 
@@ -950,16 +848,6 @@ static int __link_path_walk(const char *name, struct nameidata *nd)
                        case 1:
                                continue;
                }
-               /*
-                * See if the low-level filesystem might want
-                * to use its own hash..
-                */
-               if (nd->path.dentry->d_op && nd->path.dentry->d_op->d_hash) {
-                       err = nd->path.dentry->d_op->d_hash(nd->path.dentry,
-                                                           &this);
-                       if (err < 0)
-                               break;
-               }
                /* This does the actual lookups.. */
                err = do_lookup(nd, &this, &next);
                if (err)
@@ -969,9 +857,6 @@ static int __link_path_walk(const char *name, struct nameidata *nd)
                inode = next.dentry->d_inode;
                if (!inode)
                        goto out_dput;
-               err = -ENOTDIR; 
-               if (!inode->i_op)
-                       goto out_dput;
 
                if (inode->i_op->follow_link) {
                        err = do_follow_link(&next, nd);
@@ -981,9 +866,6 @@ static int __link_path_walk(const char *name, struct nameidata *nd)
                        inode = nd->path.dentry->d_inode;
                        if (!inode)
                                break;
-                       err = -ENOTDIR; 
-                       if (!inode->i_op)
-                               break;
                } else
                        path_to_nameidata(&next, nd);
                err = -ENOTDIR; 
@@ -1011,18 +893,12 @@ last_component:
                        case 1:
                                goto return_reval;
                }
-               if (nd->path.dentry->d_op && nd->path.dentry->d_op->d_hash) {
-                       err = nd->path.dentry->d_op->d_hash(nd->path.dentry,
-                                                           &this);
-                       if (err < 0)
-                               break;
-               }
                err = do_lookup(nd, &this, &next);
                if (err)
                        break;
                inode = next.dentry->d_inode;
                if ((lookup_flags & LOOKUP_FOLLOW)
-                   && inode && inode->i_op && inode->i_op->follow_link) {
+                   && inode && inode->i_op->follow_link) {
                        err = do_follow_link(&next, nd);
                        if (err)
                                goto return_err;
@@ -1034,7 +910,7 @@ last_component:
                        break;
                if (lookup_flags & LOOKUP_DIRECTORY) {
                        err = -ENOTDIR; 
-                       if (!inode->i_op || !inode->i_op->lookup)
+                       if (!inode->i_op->lookup)
                                break;
                }
                goto return_base;
@@ -1075,98 +951,46 @@ return_err:
 
 static int path_walk(const char *name, struct nameidata *nd)
 {
-       current->total_link_count = 0;
-       return link_path_walk(name, nd);
-}
+       struct path save = nd->path;
+       int result;
 
-/* 
- * 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))
-               return 0;               /* something went wrong... */
+       current->total_link_count = 0;
 
-       if (!nd->path.dentry->d_inode ||
-           S_ISDIR(nd->path.dentry->d_inode->i_mode)) {
-               struct path old_path = nd->path;
-               struct qstr last = nd->last;
-               int last_type = nd->last_type;
-               struct fs_struct *fs = current->fs;
+       /* make sure the stuff we saved doesn't go away */
+       path_get(&save);
 
-               /*
-                * 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(&fs->lock);
-               nd->path = fs->root;
-               path_get(&fs->root);
-               read_unlock(&fs->lock);
-               if (path_walk(name, nd) == 0) {
-                       if (nd->path.dentry->d_inode) {
-                               path_put(&old_path);
-                               return 1;
-                       }
-                       path_put(&nd->path);
-               }
-               nd->path = old_path;
-               nd->last = last;
-               nd->last_type = last_type;
+       result = link_path_walk(name, nd);
+       if (result == -ESTALE) {
+               /* nd->path had been dropped */
+               current->total_link_count = 0;
+               nd->path = save;
+               path_get(&nd->path);
+               nd->flags |= LOOKUP_REVAL;
+               result = link_path_walk(name, nd);
        }
-       return 1;
-}
 
-void set_fs_altroot(void)
-{
-       char *emul = __emul_prefix();
-       struct nameidata nd;
-       struct path path = {}, old_path;
-       int err;
-       struct fs_struct *fs = current->fs;
-
-       if (!emul)
-               goto set_it;
-       err = path_lookup(emul, LOOKUP_FOLLOW|LOOKUP_DIRECTORY|LOOKUP_NOALT, &nd);
-       if (!err)
-               path = nd.path;
-set_it:
-       write_lock(&fs->lock);
-       old_path = fs->altroot;
-       fs->altroot = path;
-       write_unlock(&fs->lock);
-       if (old_path.dentry)
-               path_put(&old_path);
+       path_put(&save);
+
+       return result;
 }
 
-/* Returns 0 and nd will be valid on success; Retuns error, otherwise. */
-static int do_path_lookup(int dfd, const char *name,
-                               unsigned int flags, struct nameidata *nd)
+static int path_init(int dfd, const char *name, unsigned int flags, struct nameidata *nd)
 {
        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;
+       nd->root.mnt = NULL;
 
        if (*name=='/') {
-               read_lock(&fs->lock);
-               if (fs->altroot.dentry && !(nd->flags & LOOKUP_NOALT)) {
-                       nd->path = fs->altroot;
-                       path_get(&fs->altroot);
-                       read_unlock(&fs->lock);
-                       if (__emul_lookup_dentry(name,nd))
-                               goto out; /* found in altroot */
-                       read_lock(&fs->lock);
-               }
-               nd->path = fs->root;
-               path_get(&fs->root);
-               read_unlock(&fs->lock);
+               set_root(nd);
+               nd->path = nd->root;
+               path_get(&nd->root);
        } else if (dfd == AT_FDCWD) {
+               struct fs_struct *fs = current->fs;
                read_lock(&fs->lock);
                nd->path = fs->pwd;
                path_get(&fs->pwd);
@@ -1194,18 +1018,29 @@ static int do_path_lookup(int dfd, const char *name,
 
                fput_light(file, fput_needed);
        }
+       return 0;
 
-       retval = path_walk(name, nd);
-out:
+fput_fail:
+       fput_light(file, fput_needed);
+out_fail:
+       return retval;
+}
+
+/* Returns 0 and nd will be valid on success; Retuns error, otherwise. */
+static int do_path_lookup(int dfd, const char *name,
+                               unsigned int flags, struct nameidata *nd)
+{
+       int retval = path_init(dfd, name, flags, nd);
+       if (!retval)
+               retval = path_walk(name, nd);
        if (unlikely(!retval && !audit_dummy_context() && nd->path.dentry &&
                                nd->path.dentry->d_inode))
                audit_inode(name, nd->path.dentry);
-out_fail:
+       if (nd->root.mnt) {
+               path_put(&nd->root);
+               nd->root.mnt = NULL;
+       }
        return retval;
-
-fput_fail:
-       fput_light(file, fput_needed);
-       goto out_fail;
 }
 
 int path_lookup(const char *name, unsigned int flags,
@@ -1214,6 +1049,15 @@ int path_lookup(const char *name, unsigned int flags,
        return do_path_lookup(AT_FDCWD, name, flags, nd);
 }
 
+int kern_path(const char *name, unsigned int flags, struct path *path)
+{
+       struct nameidata nd;
+       int res = do_path_lookup(AT_FDCWD, name, flags, &nd);
+       if (!res)
+               *path = nd.path;
+       return res;
+}
+
 /**
  * vfs_path_lookup - lookup a file path relative to a dentry-vfsmount pair
  * @dentry:  pointer to dentry of the base directory
@@ -1236,82 +1080,18 @@ int vfs_path_lookup(struct dentry *dentry, struct vfsmount *mnt,
        nd->path.dentry = dentry;
        nd->path.mnt = mnt;
        path_get(&nd->path);
+       nd->root = nd->path;
+       path_get(&nd->root);
 
        retval = path_walk(name, nd);
        if (unlikely(!retval && !audit_dummy_context() && nd->path.dentry &&
                                nd->path.dentry->d_inode))
                audit_inode(name, nd->path.dentry);
 
-       return retval;
-
-}
-
-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_put(&nd->path);
-               }
-       } 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);
+       path_put(&nd->root);
+       nd->root.mnt = NULL;
 
-       if (!IS_ERR(tmp)) {
-               err = __path_lookup_intent_open(AT_FDCWD, tmp, lookup_flags, nd, open_flags, 0);
-               putname(tmp);
-       }
-       return err;
+       return retval;
 }
 
 static struct dentry *__lookup_hash(struct qstr *name,
@@ -1334,7 +1114,17 @@ static struct dentry *__lookup_hash(struct qstr *name,
                        goto out;
        }
 
-       dentry = cached_lookup(base, name, nd);
+       dentry = __d_lookup(base, name);
+
+       /* lockess __d_lookup may fail due to concurrent d_move()
+        * in some unrelated directory, so try with d_lookup
+        */
+       if (!dentry)
+               dentry = d_lookup(base, name);
+
+       if (dentry && dentry->d_op && dentry->d_op->d_revalidate)
+               dentry = do_revalidate(dentry, nd);
+
        if (!dentry) {
                struct dentry *new;
 
@@ -1366,7 +1156,7 @@ static struct dentry *lookup_hash(struct nameidata *nd)
 {
        int err;
 
-       err = permission(nd->path.dentry->d_inode, MAY_EXEC, nd);
+       err = exec_permission(nd->path.dentry->d_inode);
        if (err)
                return ERR_PTR(err);
        return __lookup_hash(&nd->last, nd->path.dentry, nd);
@@ -1410,54 +1200,52 @@ struct dentry *lookup_one_len(const char *name, struct dentry *base, int len)
        int err;
        struct qstr this;
 
-       err = __lookup_one_len(name, &this, base, len);
-       if (err)
-               return ERR_PTR(err);
+       WARN_ON_ONCE(!mutex_is_locked(&base->d_inode->i_mutex));
 
-       err = permission(base->d_inode, MAY_EXEC, NULL);
+       err = __lookup_one_len(name, &this, base, len);
        if (err)
                return ERR_PTR(err);
-       return __lookup_hash(&this, base, NULL);
-}
-
-/**
- * lookup_one_noperm - bad hack for sysfs
- * @name:      pathname component to lookup
- * @base:      base directory to lookup from
- *
- * This is a variant of lookup_one_len that doesn't perform any permission
- * checks.   It's a horrible hack to work around the braindead sysfs
- * architecture and should not be used anywhere else.
- *
- * DON'T USE THIS FUNCTION EVER, thanks.
- */
-struct dentry *lookup_one_noperm(const char *name, struct dentry *base)
-{
-       int err;
-       struct qstr this;
 
-       err = __lookup_one_len(name, &this, base, strlen(name));
+       err = exec_permission(base->d_inode);
        if (err)
                return ERR_PTR(err);
        return __lookup_hash(&this, base, NULL);
 }
 
-int __user_walk_fd(int dfd, const char __user *name, unsigned flags,
-                           struct nameidata *nd)
+int user_path_at(int dfd, const char __user *name, unsigned flags,
+                struct path *path)
 {
+       struct nameidata nd;
        char *tmp = getname(name);
        int err = PTR_ERR(tmp);
-
        if (!IS_ERR(tmp)) {
-               err = do_path_lookup(dfd, tmp, flags, nd);
+
+               BUG_ON(flags & LOOKUP_PARENT);
+
+               err = do_path_lookup(dfd, tmp, flags, &nd);
                putname(tmp);
+               if (!err)
+                       *path = nd.path;
        }
        return err;
 }
 
-int __user_walk(const char __user *name, unsigned flags, struct nameidata *nd)
+static int user_path_parent(int dfd, const char __user *path,
+                       struct nameidata *nd, char **name)
 {
-       return __user_walk_fd(AT_FDCWD, name, flags, nd);
+       char *s = getname(path);
+       int error;
+
+       if (IS_ERR(s))
+               return PTR_ERR(s);
+
+       error = do_path_lookup(dfd, s, LOOKUP_PARENT, nd);
+       if (error)
+               putname(s);
+       else
+               *name = s;
+
+       return error;
 }
 
 /*
@@ -1466,11 +1254,13 @@ int __user_walk(const char __user *name, unsigned flags, struct nameidata *nd)
  */
 static inline int check_sticky(struct inode *dir, struct inode *inode)
 {
+       uid_t fsuid = current_fsuid();
+
        if (!(dir->i_mode & S_ISVTX))
                return 0;
-       if (inode->i_uid == current->fsuid)
+       if (inode->i_uid == fsuid)
                return 0;
-       if (dir->i_uid == current->fsuid)
+       if (dir->i_uid == fsuid)
                return 0;
        return !capable(CAP_FOWNER);
 }
@@ -1504,13 +1294,13 @@ static int may_delete(struct inode *dir,struct dentry *victim,int isdir)
        BUG_ON(victim->d_parent->d_inode != dir);
        audit_inode_child(victim->d_name.name, victim, dir);
 
-       error = permission(dir,MAY_WRITE | MAY_EXEC, NULL);
+       error = inode_permission(dir, MAY_WRITE | MAY_EXEC);
        if (error)
                return error;
        if (IS_APPEND(dir))
                return -EPERM;
        if (check_sticky(dir, victim->d_inode)||IS_APPEND(victim->d_inode)||
-           IS_IMMUTABLE(victim->d_inode))
+           IS_IMMUTABLE(victim->d_inode) || IS_SWAPFILE(victim->d_inode))
                return -EPERM;
        if (isdir) {
                if (!S_ISDIR(victim->d_inode->i_mode))
@@ -1534,14 +1324,13 @@ static int may_delete(struct inode *dir,struct dentry *victim,int isdir)
  *  3. We should have write and exec permissions on dir
  *  4. We can't do it if dir is immutable (done in permission())
  */
-static inline int may_create(struct inode *dir, struct dentry *child,
-                            struct nameidata *nd)
+static inline int may_create(struct inode *dir, struct dentry *child)
 {
        if (child->d_inode)
                return -EEXIST;
        if (IS_DEADDIR(dir))
                return -ENOENT;
-       return permission(dir,MAY_WRITE | MAY_EXEC, nd);
+       return inode_permission(dir, MAY_WRITE | MAY_EXEC);
 }
 
 /* 
@@ -1574,20 +1363,18 @@ struct dentry *lock_rename(struct dentry *p1, struct dentry *p2)
 
        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) {
-                       mutex_lock_nested(&p2->d_inode->i_mutex, I_MUTEX_PARENT);
-                       mutex_lock_nested(&p1->d_inode->i_mutex, I_MUTEX_CHILD);
-                       return p;
-               }
+       p = d_ancestor(p2, p1);
+       if (p) {
+               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) {
-                       mutex_lock_nested(&p1->d_inode->i_mutex, I_MUTEX_PARENT);
-                       mutex_lock_nested(&p2->d_inode->i_mutex, I_MUTEX_CHILD);
-                       return p;
-               }
+       p = d_ancestor(p1, p2);
+       if (p) {
+               mutex_lock_nested(&p1->d_inode->i_mutex, I_MUTEX_PARENT);
+               mutex_lock_nested(&p2->d_inode->i_mutex, I_MUTEX_CHILD);
+               return p;
        }
 
        mutex_lock_nested(&p1->d_inode->i_mutex, I_MUTEX_PARENT);
@@ -1607,57 +1394,56 @@ void unlock_rename(struct dentry *p1, struct dentry *p2)
 int vfs_create(struct inode *dir, struct dentry *dentry, int mode,
                struct nameidata *nd)
 {
-       int error = may_create(dir, dentry, nd);
+       int error = may_create(dir, dentry);
 
        if (error)
                return error;
 
-       if (!dir->i_op || !dir->i_op->create)
+       if (!dir->i_op->create)
                return -EACCES; /* shouldn't it be ENOSYS? */
        mode &= S_IALLUGO;
        mode |= S_IFREG;
        error = security_inode_create(dir, dentry, mode);
        if (error)
                return error;
-       DQUOT_INIT(dir);
+       vfs_dq_init(dir);
        error = dir->i_op->create(dir, dentry, mode, nd);
        if (!error)
                fsnotify_create(dir, dentry);
        return error;
 }
 
-int may_open(struct nameidata *nd, int acc_mode, int flag)
+int may_open(struct path *path, int acc_mode, int flag)
 {
-       struct dentry *dentry = nd->path.dentry;
+       struct dentry *dentry = path->dentry;
        struct inode *inode = dentry->d_inode;
        int error;
 
        if (!inode)
                return -ENOENT;
 
-       if (S_ISLNK(inode->i_mode))
+       switch (inode->i_mode & S_IFMT) {
+       case S_IFLNK:
                return -ELOOP;
-       
-       if (S_ISDIR(inode->i_mode) && (acc_mode & MAY_WRITE))
-               return -EISDIR;
-
-       /*
-        * FIFO's, sockets and device files are special: they don't
-        * actually live on the filesystem itself, and as such you
-        * can write to them even if the filesystem is read-only.
-        */
-       if (S_ISFIFO(inode->i_mode) || S_ISSOCK(inode->i_mode)) {
-               flag &= ~O_TRUNC;
-       } else if (S_ISBLK(inode->i_mode) || S_ISCHR(inode->i_mode)) {
-               if (nd->path.mnt->mnt_flags & MNT_NODEV)
+       case S_IFDIR:
+               if (acc_mode & MAY_WRITE)
+                       return -EISDIR;
+               break;
+       case S_IFBLK:
+       case S_IFCHR:
+               if (path->mnt->mnt_flags & MNT_NODEV)
                        return -EACCES;
-
+               /*FALLTHRU*/
+       case S_IFIFO:
+       case S_IFSOCK:
                flag &= ~O_TRUNC;
+               break;
        }
 
-       error = vfs_permission(nd, acc_mode);
+       error = inode_permission(inode, acc_mode);
        if (error)
                return error;
+
        /*
         * An append-only file must be opened in append mode for writing.
         */
@@ -1669,41 +1455,35 @@ int may_open(struct nameidata *nd, int acc_mode, int flag)
        }
 
        /* O_NOATIME can only be set by the owner or superuser */
-       if (flag & O_NOATIME)
-               if (!is_owner_or_cap(inode))
-                       return -EPERM;
+       if (flag & O_NOATIME && !is_owner_or_cap(inode))
+               return -EPERM;
 
        /*
         * Ensure there are no outstanding leases on the file.
         */
-       error = break_lease(inode, flag);
+       return break_lease(inode, flag);
+}
+
+static int handle_truncate(struct path *path)
+{
+       struct inode *inode = path->dentry->d_inode;
+       int error = get_write_access(inode);
        if (error)
                return error;
-
-       if (flag & O_TRUNC) {
-               error = get_write_access(inode);
-               if (error)
-                       return error;
-
-               /*
-                * Refuse to truncate files with mandatory locks held on them.
-                */
-               error = locks_verify_locked(inode);
-               if (!error) {
-                       DQUOT_INIT(inode);
-
-                       error = do_truncate(dentry, 0,
-                                           ATTR_MTIME|ATTR_CTIME|ATTR_OPEN,
-                                           NULL);
-               }
-               put_write_access(inode);
-               if (error)
-                       return error;
-       } else
-               if (flag & FMODE_WRITE)
-                       DQUOT_INIT(inode);
-
-       return 0;
+       /*
+        * Refuse to truncate files with mandatory locks held on them.
+        */
+       error = locks_verify_locked(inode);
+       if (!error)
+               error = security_path_truncate(path, 0,
+                                      ATTR_MTIME|ATTR_CTIME|ATTR_OPEN);
+       if (!error) {
+               error = do_truncate(path->dentry, 0,
+                                   ATTR_MTIME|ATTR_CTIME|ATTR_OPEN,
+                                   NULL);
+       }
+       put_write_access(inode);
+       return error;
 }
 
 /*
@@ -1718,15 +1498,19 @@ static int __open_namei_create(struct nameidata *nd, struct path *path,
        struct dentry *dir = nd->path.dentry;
 
        if (!IS_POSIXACL(dir->d_inode))
-               mode &= ~current->fs->umask;
+               mode &= ~current_umask();
+       error = security_path_mknod(&nd->path, path->dentry, mode, 0);
+       if (error)
+               goto out_unlock;
        error = vfs_create(dir->d_inode, path->dentry, mode, nd);
+out_unlock:
        mutex_unlock(&dir->d_inode->i_mutex);
        dput(nd->path.dentry);
        nd->path.dentry = path->dentry;
        if (error)
                return error;
        /* Don't check for write permission, don't truncate */
-       return may_open(nd, 0, flag & ~O_TRUNC);
+       return may_open(&nd->path, 0, flag & ~O_TRUNC);
 }
 
 /*
@@ -1753,7 +1537,7 @@ static inline int open_to_namei_flags(int flag)
        return flag;
 }
 
-static int open_will_write_to_fs(int flag, struct inode *inode)
+static int open_will_truncate(int flag, struct inode *inode)
 {
        /*
         * We'll never write to the fs underlying
@@ -1770,18 +1554,28 @@ static int open_will_write_to_fs(int flag, struct inode *inode)
  * open_to_namei_flags() for more details.
  */
 struct file *do_filp_open(int dfd, const char *pathname,
-               int open_flag, int mode)
+               int open_flag, int mode, int acc_mode)
 {
        struct file *filp;
        struct nameidata nd;
-       int acc_mode, error;
-       struct path path;
+       int error;
+       struct path path, save;
        struct dentry *dir;
        int count = 0;
-       int will_write;
+       int will_truncate;
        int flag = open_to_namei_flags(open_flag);
 
-       acc_mode = ACC_MODE(flag);
+       /*
+        * O_SYNC is implemented as __O_SYNC|O_DSYNC.  As many places only
+        * check for O_DSYNC if the need any syncing at all we enforce it's
+        * always set instead of having to deal with possibly weird behaviour
+        * for malicious applications setting only __O_SYNC.
+        */
+       if (open_flag & __O_SYNC)
+               open_flag |= O_DSYNC;
+
+       if (!acc_mode)
+               acc_mode = MAY_OPEN | ACC_MODE(flag);
 
        /* O_TRUNC implies we need access checks for write permissions */
        if (flag & O_TRUNC)
@@ -1796,8 +1590,22 @@ struct file *do_filp_open(int dfd, const char *pathname,
         * The simplest case - just a plain lookup.
         */
        if (!(flag & O_CREAT)) {
-               error = path_lookup_open(dfd, pathname, lookup_flags(flag),
-                                        &nd, flag);
+               filp = get_empty_filp();
+
+               if (filp == NULL)
+                       return ERR_PTR(-ENFILE);
+               nd.intent.open.file = filp;
+               nd.intent.open.flags = flag;
+               nd.intent.open.create_mode = 0;
+               error = do_path_lookup(dfd, pathname,
+                                       lookup_flags(flag)|LOOKUP_OPEN, &nd);
+               if (IS_ERR(nd.intent.open.file)) {
+                       if (error == 0) {
+                               error = PTR_ERR(nd.intent.open.file);
+                               path_put(&nd.path);
+                       }
+               } else if (error)
+                       release_open_intent(&nd);
                if (error)
                        return ERR_PTR(error);
                goto ok;
@@ -1806,10 +1614,17 @@ struct file *do_filp_open(int dfd, const char *pathname,
        /*
         * Create - we need to know the parent.
         */
-       error = path_lookup_create(dfd, pathname, LOOKUP_PARENT,
-                                  &nd, flag, mode);
+       error = path_init(dfd, pathname, LOOKUP_PARENT, &nd);
        if (error)
                return ERR_PTR(error);
+       error = path_walk(pathname, &nd);
+       if (error) {
+               if (nd.root.mnt)
+                       path_put(&nd.root);
+               return ERR_PTR(error);
+       }
+       if (unlikely(!audit_dummy_context()))
+               audit_inode(pathname, nd.path.dentry);
 
        /*
         * We have the parent and last component. First of all, check
@@ -1818,10 +1633,20 @@ struct file *do_filp_open(int dfd, const char *pathname,
         */
        error = -EISDIR;
        if (nd.last_type != LAST_NORM || nd.last.name[nd.last.len])
-               goto exit;
+               goto exit_parent;
 
+       error = -ENFILE;
+       filp = get_empty_filp();
+       if (filp == NULL)
+               goto exit_parent;
+       nd.intent.open.file = filp;
+       nd.intent.open.flags = flag;
+       nd.intent.open.create_mode = mode;
        dir = nd.path.dentry;
        nd.flags &= ~LOOKUP_PARENT;
+       nd.flags |= LOOKUP_CREATE | LOOKUP_OPEN;
+       if (flag & O_EXCL)
+               nd.flags |= LOOKUP_EXCL;
        mutex_lock(&dir->d_inode->i_mutex);
        path.dentry = lookup_hash(&nd);
        path.mnt = nd.path.mnt;
@@ -1857,6 +1682,16 @@ do_last:
                }
                filp = nameidata_to_filp(&nd, open_flag);
                mnt_drop_write(nd.path.mnt);
+               if (nd.root.mnt)
+                       path_put(&nd.root);
+               if (!IS_ERR(filp)) {
+                       error = ima_path_check(&filp->f_path, filp->f_mode &
+                                      (MAY_READ | MAY_WRITE | MAY_EXEC), 0);
+                       if (error) {
+                               fput(filp);
+                               filp = ERR_PTR(error);
+                       }
+               }
                return filp;
        }
 
@@ -1879,7 +1714,7 @@ do_last:
        error = -ENOENT;
        if (!path.dentry->d_inode)
                goto exit_dput;
-       if (path.dentry->d_inode->i_op && path.dentry->d_inode->i_op->follow_link)
+       if (path.dentry->d_inode->i_op->follow_link)
                goto do_link;
 
        path_to_nameidata(&path, &nd);
@@ -1897,26 +1732,48 @@ ok:
         * be avoided. Taking this mnt write here
         * ensures that (2) can not occur.
         */
-       will_write = open_will_write_to_fs(flag, nd.path.dentry->d_inode);
-       if (will_write) {
+       will_truncate = open_will_truncate(flag, nd.path.dentry->d_inode);
+       if (will_truncate) {
                error = mnt_want_write(nd.path.mnt);
                if (error)
                        goto exit;
        }
-       error = may_open(&nd, acc_mode, flag);
+       error = may_open(&nd.path, acc_mode, flag);
        if (error) {
-               if (will_write)
+               if (will_truncate)
                        mnt_drop_write(nd.path.mnt);
                goto exit;
        }
        filp = nameidata_to_filp(&nd, open_flag);
+       if (!IS_ERR(filp)) {
+               error = ima_path_check(&filp->f_path, filp->f_mode &
+                              (MAY_READ | MAY_WRITE | MAY_EXEC), 0);
+               if (error) {
+                       fput(filp);
+                       filp = ERR_PTR(error);
+               }
+       }
+       if (!IS_ERR(filp)) {
+               if (acc_mode & MAY_WRITE)
+                       vfs_dq_init(nd.path.dentry->d_inode);
+
+               if (will_truncate) {
+                       error = handle_truncate(&nd.path);
+                       if (error) {
+                               fput(filp);
+                               filp = ERR_PTR(error);
+                       }
+               }
+       }
        /*
         * It is now safe to drop the mnt write
         * because the filp has had a write taken
         * on its behalf.
         */
-       if (will_write)
+       if (will_truncate)
                mnt_drop_write(nd.path.mnt);
+       if (nd.root.mnt)
+               path_put(&nd.root);
        return filp;
 
 exit_mutex_unlock:
@@ -1926,6 +1783,9 @@ exit_dput:
 exit:
        if (!IS_ERR(nd.intent.open.file))
                release_open_intent(&nd);
+exit_parent:
+       if (nd.root.mnt)
+               path_put(&nd.root);
        path_put(&nd.path);
        return ERR_PTR(error);
 
@@ -1947,13 +1807,26 @@ do_link:
        error = security_inode_follow_link(path.dentry, &nd);
        if (error)
                goto exit_dput;
+       save = nd.path;
+       path_get(&save);
        error = __do_follow_link(&path, &nd);
+       if (error == -ESTALE) {
+               /* nd.path had been dropped */
+               nd.path = save;
+               path_get(&nd.path);
+               nd.flags |= LOOKUP_REVAL;
+               error = __do_follow_link(&path, &nd);
+       }
+       path_put(&save);
+       path_put(&path);
        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);
+               if (nd.root.mnt)
+                       path_put(&nd.root);
                return ERR_PTR(error);
        }
        nd.flags &= ~LOOKUP_PARENT;
@@ -1992,7 +1865,7 @@ do_link:
  */
 struct file *filp_open(const char *filename, int flags, int mode)
 {
-       return do_filp_open(AT_FDCWD, filename, flags, mode);
+       return do_filp_open(AT_FDCWD, filename, flags, mode, 0);
 }
 EXPORT_SYMBOL(filp_open);
 
@@ -2018,7 +1891,7 @@ struct dentry *lookup_create(struct nameidata *nd, int is_dir)
        if (nd->last_type != LAST_NORM)
                goto fail;
        nd->flags &= ~LOOKUP_PARENT;
-       nd->flags |= LOOKUP_CREATE;
+       nd->flags |= LOOKUP_CREATE | LOOKUP_EXCL;
        nd->intent.open.flags = O_EXCL;
 
        /*
@@ -2051,7 +1924,7 @@ EXPORT_SYMBOL_GPL(lookup_create);
 
 int vfs_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev)
 {
-       int error = may_create(dir, dentry, NULL);
+       int error = may_create(dir, dentry);
 
        if (error)
                return error;
@@ -2059,7 +1932,7 @@ int vfs_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev)
        if ((S_ISCHR(mode) || S_ISBLK(mode)) && !capable(CAP_MKNOD))
                return -EPERM;
 
-       if (!dir->i_op || !dir->i_op->mknod)
+       if (!dir->i_op->mknod)
                return -EPERM;
 
        error = devcgroup_inode_mknod(mode, dev);
@@ -2070,7 +1943,7 @@ int vfs_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev)
        if (error)
                return error;
 
-       DQUOT_INIT(dir);
+       vfs_dq_init(dir);
        error = dir->i_op->mknod(dir, dentry, mode, dev);
        if (!error)
                fsnotify_create(dir, dentry);
@@ -2094,36 +1967,37 @@ static int may_mknod(mode_t mode)
        }
 }
 
-asmlinkage long sys_mknodat(int dfd, const char __user *filename, int mode,
-                               unsigned dev)
+SYSCALL_DEFINE4(mknodat, int, dfd, const char __user *, filename, int, mode,
+               unsigned, dev)
 {
-       int error = 0;
-       char * tmp;
-       struct dentry * dentry;
+       int error;
+       char *tmp;
+       struct dentry *dentry;
        struct nameidata nd;
 
        if (S_ISDIR(mode))
                return -EPERM;
-       tmp = getname(filename);
-       if (IS_ERR(tmp))
-               return PTR_ERR(tmp);
 
-       error = do_path_lookup(dfd, tmp, LOOKUP_PARENT, &nd);
+       error = user_path_parent(dfd, filename, &nd, &tmp);
        if (error)
-               goto out;
+               return error;
+
        dentry = lookup_create(&nd, 0);
        if (IS_ERR(dentry)) {
                error = PTR_ERR(dentry);
                goto out_unlock;
        }
        if (!IS_POSIXACL(nd.path.dentry->d_inode))
-               mode &= ~current->fs->umask;
+               mode &= ~current_umask();
        error = may_mknod(mode);
        if (error)
                goto out_dput;
        error = mnt_want_write(nd.path.mnt);
        if (error)
                goto out_dput;
+       error = security_path_mknod(&nd.path, dentry, mode, dev);
+       if (error)
+               goto out_drop_write;
        switch (mode & S_IFMT) {
                case 0: case S_IFREG:
                        error = vfs_create(nd.path.dentry->d_inode,dentry,mode,&nd);
@@ -2136,31 +2010,31 @@ asmlinkage long sys_mknodat(int dfd, const char __user *filename, int mode,
                        error = vfs_mknod(nd.path.dentry->d_inode,dentry,mode,0);
                        break;
        }
+out_drop_write:
        mnt_drop_write(nd.path.mnt);
 out_dput:
        dput(dentry);
 out_unlock:
        mutex_unlock(&nd.path.dentry->d_inode->i_mutex);
        path_put(&nd.path);
-out:
        putname(tmp);
 
        return error;
 }
 
-asmlinkage long sys_mknod(const char __user *filename, int mode, unsigned dev)
+SYSCALL_DEFINE3(mknod, const char __user *, filename, int, mode, unsigned, dev)
 {
        return sys_mknodat(AT_FDCWD, filename, mode, dev);
 }
 
 int vfs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
 {
-       int error = may_create(dir, dentry, NULL);
+       int error = may_create(dir, dentry);
 
        if (error)
                return error;
 
-       if (!dir->i_op || !dir->i_op->mkdir)
+       if (!dir->i_op->mkdir)
                return -EPERM;
 
        mode &= (S_IRWXUGO|S_ISVTX);
@@ -2168,52 +2042,51 @@ int vfs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
        if (error)
                return error;
 
-       DQUOT_INIT(dir);
+       vfs_dq_init(dir);
        error = dir->i_op->mkdir(dir, dentry, mode);
        if (!error)
                fsnotify_mkdir(dir, dentry);
        return error;
 }
 
-asmlinkage long sys_mkdirat(int dfd, const char __user *pathname, int mode)
+SYSCALL_DEFINE3(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))
+       error = user_path_parent(dfd, pathname, &nd, &tmp);
+       if (error)
                goto out_err;
 
-       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.path.dentry->d_inode))
-               mode &= ~current->fs->umask;
+               mode &= ~current_umask();
        error = mnt_want_write(nd.path.mnt);
        if (error)
                goto out_dput;
+       error = security_path_mkdir(&nd.path, dentry, mode);
+       if (error)
+               goto out_drop_write;
        error = vfs_mkdir(nd.path.dentry->d_inode, dentry, mode);
+out_drop_write:
        mnt_drop_write(nd.path.mnt);
 out_dput:
        dput(dentry);
 out_unlock:
        mutex_unlock(&nd.path.dentry->d_inode->i_mutex);
        path_put(&nd.path);
-out:
        putname(tmp);
 out_err:
        return error;
 }
 
-asmlinkage long sys_mkdir(const char __user *pathname, int mode)
+SYSCALL_DEFINE2(mkdir, const char __user *, pathname, int, mode)
 {
        return sys_mkdirat(AT_FDCWD, pathname, mode);
 }
@@ -2252,10 +2125,10 @@ int vfs_rmdir(struct inode *dir, struct dentry *dentry)
        if (error)
                return error;
 
-       if (!dir->i_op || !dir->i_op->rmdir)
+       if (!dir->i_op->rmdir)
                return -EPERM;
 
-       DQUOT_INIT(dir);
+       vfs_dq_init(dir);
 
        mutex_lock(&dentry->d_inode->i_mutex);
        dentry_unhash(dentry);
@@ -2285,25 +2158,24 @@ static long do_rmdir(int dfd, const char __user *pathname)
        struct dentry *dentry;
        struct nameidata nd;
 
-       name = getname(pathname);
-       if(IS_ERR(name))
-               return PTR_ERR(name);
-
-       error = do_path_lookup(dfd, name, LOOKUP_PARENT, &nd);
+       error = user_path_parent(dfd, pathname, &nd, &name);
        if (error)
-               goto exit;
+               return error;
 
        switch(nd.last_type) {
-               case LAST_DOTDOT:
-                       error = -ENOTEMPTY;
-                       goto exit1;
-               case LAST_DOT:
-                       error = -EINVAL;
-                       goto exit1;
-               case LAST_ROOT:
-                       error = -EBUSY;
-                       goto exit1;
+       case LAST_DOTDOT:
+               error = -ENOTEMPTY;
+               goto exit1;
+       case LAST_DOT:
+               error = -EINVAL;
+               goto exit1;
+       case LAST_ROOT:
+               error = -EBUSY;
+               goto exit1;
        }
+
+       nd.flags &= ~LOOKUP_PARENT;
+
        mutex_lock_nested(&nd.path.dentry->d_inode->i_mutex, I_MUTEX_PARENT);
        dentry = lookup_hash(&nd);
        error = PTR_ERR(dentry);
@@ -2312,7 +2184,11 @@ static long do_rmdir(int dfd, const char __user *pathname)
        error = mnt_want_write(nd.path.mnt);
        if (error)
                goto exit3;
+       error = security_path_rmdir(&nd.path, dentry);
+       if (error)
+               goto exit4;
        error = vfs_rmdir(nd.path.dentry->d_inode, dentry);
+exit4:
        mnt_drop_write(nd.path.mnt);
 exit3:
        dput(dentry);
@@ -2320,12 +2196,11 @@ exit2:
        mutex_unlock(&nd.path.dentry->d_inode->i_mutex);
 exit1:
        path_put(&nd.path);
-exit:
        putname(name);
        return error;
 }
 
-asmlinkage long sys_rmdir(const char __user *pathname)
+SYSCALL_DEFINE1(rmdir, const char __user *, pathname)
 {
        return do_rmdir(AT_FDCWD, pathname);
 }
@@ -2337,10 +2212,10 @@ int vfs_unlink(struct inode *dir, struct dentry *dentry)
        if (error)
                return error;
 
-       if (!dir->i_op || !dir->i_op->unlink)
+       if (!dir->i_op->unlink)
                return -EPERM;
 
-       DQUOT_INIT(dir);
+       vfs_dq_init(dir);
 
        mutex_lock(&dentry->d_inode->i_mutex);
        if (d_mountpoint(dentry))
@@ -2369,22 +2244,22 @@ int vfs_unlink(struct inode *dir, struct dentry *dentry)
  */
 static long do_unlinkat(int dfd, const char __user *pathname)
 {
-       int error = 0;
-       char * name;
+       int error;
+       char *name;
        struct dentry *dentry;
        struct nameidata nd;
        struct inode *inode = NULL;
 
-       name = getname(pathname);
-       if(IS_ERR(name))
-               return PTR_ERR(name);
-
-       error = do_path_lookup(dfd, name, LOOKUP_PARENT, &nd);
+       error = user_path_parent(dfd, pathname, &nd, &name);
        if (error)
-               goto exit;
+               return error;
+
        error = -EISDIR;
        if (nd.last_type != LAST_NORM)
                goto exit1;
+
+       nd.flags &= ~LOOKUP_PARENT;
+
        mutex_lock_nested(&nd.path.dentry->d_inode->i_mutex, I_MUTEX_PARENT);
        dentry = lookup_hash(&nd);
        error = PTR_ERR(dentry);
@@ -2398,7 +2273,11 @@ static long do_unlinkat(int dfd, const char __user *pathname)
                error = mnt_want_write(nd.path.mnt);
                if (error)
                        goto exit2;
+               error = security_path_unlink(&nd.path, dentry);
+               if (error)
+                       goto exit3;
                error = vfs_unlink(nd.path.dentry->d_inode, dentry);
+exit3:
                mnt_drop_write(nd.path.mnt);
        exit2:
                dput(dentry);
@@ -2408,7 +2287,6 @@ static long do_unlinkat(int dfd, const char __user *pathname)
                iput(inode);    /* truncate the inode here */
 exit1:
        path_put(&nd.path);
-exit:
        putname(name);
        return error;
 
@@ -2418,7 +2296,7 @@ slashes:
        goto exit2;
 }
 
-asmlinkage long sys_unlinkat(int dfd, const char __user *pathname, int flag)
+SYSCALL_DEFINE3(unlinkat, int, dfd, const char __user *, pathname, int, flag)
 {
        if ((flag & ~AT_REMOVEDIR) != 0)
                return -EINVAL;
@@ -2429,52 +2307,49 @@ asmlinkage long sys_unlinkat(int dfd, const char __user *pathname, int flag)
        return do_unlinkat(dfd, pathname);
 }
 
-asmlinkage long sys_unlink(const char __user *pathname)
+SYSCALL_DEFINE1(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)
+int vfs_symlink(struct inode *dir, struct dentry *dentry, const char *oldname)
 {
-       int error = may_create(dir, dentry, NULL);
+       int error = may_create(dir, dentry);
 
        if (error)
                return error;
 
-       if (!dir->i_op || !dir->i_op->symlink)
+       if (!dir->i_op->symlink)
                return -EPERM;
 
        error = security_inode_symlink(dir, dentry, oldname);
        if (error)
                return error;
 
-       DQUOT_INIT(dir);
+       vfs_dq_init(dir);
        error = dir->i_op->symlink(dir, dentry, oldname);
        if (!error)
                fsnotify_create(dir, dentry);
        return error;
 }
 
-asmlinkage long sys_symlinkat(const char __user *oldname,
-                             int newdfd, const char __user *newname)
+SYSCALL_DEFINE3(symlinkat, const char __user *, oldname,
+               int, newdfd, const char __user *, newname)
 {
-       int error = 0;
-       char * from;
-       char * to;
+       int error;
+       char *from;
+       char *to;
        struct dentry *dentry;
        struct nameidata nd;
 
        from = getname(oldname);
-       if(IS_ERR(from))
+       if (IS_ERR(from))
                return PTR_ERR(from);
-       to = getname(newname);
-       error = PTR_ERR(to);
-       if (IS_ERR(to))
-               goto out_putname;
 
-       error = do_path_lookup(newdfd, to, LOOKUP_PARENT, &nd);
+       error = user_path_parent(newdfd, newname, &nd, &to);
        if (error)
-               goto out;
+               goto out_putname;
+
        dentry = lookup_create(&nd, 0);
        error = PTR_ERR(dentry);
        if (IS_ERR(dentry))
@@ -2483,21 +2358,24 @@ asmlinkage long sys_symlinkat(const char __user *oldname,
        error = mnt_want_write(nd.path.mnt);
        if (error)
                goto out_dput;
-       error = vfs_symlink(nd.path.dentry->d_inode, dentry, from, S_IALLUGO);
+       error = security_path_symlink(&nd.path, dentry, from);
+       if (error)
+               goto out_drop_write;
+       error = vfs_symlink(nd.path.dentry->d_inode, dentry, from);
+out_drop_write:
        mnt_drop_write(nd.path.mnt);
 out_dput:
        dput(dentry);
 out_unlock:
        mutex_unlock(&nd.path.dentry->d_inode->i_mutex);
        path_put(&nd.path);
-out:
        putname(to);
 out_putname:
        putname(from);
        return error;
 }
 
-asmlinkage long sys_symlink(const char __user *oldname, const char __user *newname)
+SYSCALL_DEFINE2(symlink, const char __user *, oldname, const char __user *, newname)
 {
        return sys_symlinkat(oldname, AT_FDCWD, newname);
 }
@@ -2510,7 +2388,7 @@ int vfs_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_de
        if (!inode)
                return -ENOENT;
 
-       error = may_create(dir, new_dentry, NULL);
+       error = may_create(dir, new_dentry);
        if (error)
                return error;
 
@@ -2522,7 +2400,7 @@ int vfs_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_de
         */
        if (IS_APPEND(inode) || IS_IMMUTABLE(inode))
                return -EPERM;
-       if (!dir->i_op || !dir->i_op->link)
+       if (!dir->i_op->link)
                return -EPERM;
        if (S_ISDIR(inode->i_mode))
                return -EPERM;
@@ -2532,7 +2410,7 @@ int vfs_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_de
                return error;
 
        mutex_lock(&inode->i_mutex);
-       DQUOT_INIT(dir);
+       vfs_dq_init(dir);
        error = dir->i_op->link(old_dentry, dir, new_dentry);
        mutex_unlock(&inode->i_mutex);
        if (!error)
@@ -2549,32 +2427,29 @@ int vfs_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_de
  * with linux 2.0, and to avoid hard-linking to directories
  * and other special files.  --ADM
  */
-asmlinkage long sys_linkat(int olddfd, const char __user *oldname,
-                          int newdfd, const char __user *newname,
-                          int flags)
+SYSCALL_DEFINE5(linkat, int, olddfd, const char __user *, oldname,
+               int, newdfd, const char __user *, newname, int, flags)
 {
        struct dentry *new_dentry;
-       struct nameidata nd, old_nd;
+       struct nameidata nd;
+       struct path old_path;
        int error;
-       char * to;
+       char *to;
 
        if ((flags & ~AT_SYMLINK_FOLLOW) != 0)
                return -EINVAL;
 
-       to = getname(newname);
-       if (IS_ERR(to))
-               return PTR_ERR(to);
-
-       error = __user_walk_fd(olddfd, oldname,
-                              flags & AT_SYMLINK_FOLLOW ? LOOKUP_FOLLOW : 0,
-                              &old_nd);
+       error = user_path_at(olddfd, oldname,
+                            flags & AT_SYMLINK_FOLLOW ? LOOKUP_FOLLOW : 0,
+                            &old_path);
        if (error)
-               goto exit;
-       error = do_path_lookup(newdfd, to, LOOKUP_PARENT, &nd);
+               return error;
+
+       error = user_path_parent(newdfd, newname, &nd, &to);
        if (error)
                goto out;
        error = -EXDEV;
-       if (old_nd.path.mnt != nd.path.mnt)
+       if (old_path.mnt != nd.path.mnt)
                goto out_release;
        new_dentry = lookup_create(&nd, 0);
        error = PTR_ERR(new_dentry);
@@ -2583,7 +2458,11 @@ asmlinkage long sys_linkat(int olddfd, const char __user *oldname,
        error = mnt_want_write(nd.path.mnt);
        if (error)
                goto out_dput;
-       error = vfs_link(old_nd.path.dentry, nd.path.dentry->d_inode, new_dentry);
+       error = security_path_link(old_path.dentry, &nd.path, new_dentry);
+       if (error)
+               goto out_drop_write;
+       error = vfs_link(old_path.dentry, nd.path.dentry->d_inode, new_dentry);
+out_drop_write:
        mnt_drop_write(nd.path.mnt);
 out_dput:
        dput(new_dentry);
@@ -2591,15 +2470,14 @@ out_unlock:
        mutex_unlock(&nd.path.dentry->d_inode->i_mutex);
 out_release:
        path_put(&nd.path);
-out:
-       path_put(&old_nd.path);
-exit:
        putname(to);
+out:
+       path_put(&old_path);
 
        return error;
 }
 
-asmlinkage long sys_link(const char __user *oldname, const char __user *newname)
+SYSCALL_DEFINE2(link, const char __user *, oldname, const char __user *, newname)
 {
        return sys_linkat(AT_FDCWD, oldname, AT_FDCWD, newname, 0);
 }
@@ -2647,7 +2525,7 @@ static int vfs_rename_dir(struct inode *old_dir, struct dentry *old_dentry,
         * we'll need to flip '..'.
         */
        if (new_dir != old_dir) {
-               error = permission(old_dentry->d_inode, MAY_WRITE, NULL);
+               error = inode_permission(old_dentry->d_inode, MAY_WRITE);
                if (error)
                        return error;
        }
@@ -2722,17 +2600,17 @@ int vfs_rename(struct inode *old_dir, struct dentry *old_dentry,
                return error;
 
        if (!new_dentry->d_inode)
-               error = may_create(new_dir, new_dentry, NULL);
+               error = may_create(new_dir, new_dentry);
        else
                error = may_delete(new_dir, new_dentry, is_dir);
        if (error)
                return error;
 
-       if (!old_dir->i_op || !old_dir->i_op->rename)
+       if (!old_dir->i_op->rename)
                return -EPERM;
 
-       DQUOT_INIT(old_dir);
-       DQUOT_INIT(new_dir);
+       vfs_dq_init(old_dir);
+       vfs_dq_init(new_dir);
 
        old_name = fsnotify_oldname_init(old_dentry->d_name.name);
 
@@ -2750,20 +2628,22 @@ int vfs_rename(struct inode *old_dir, struct dentry *old_dentry,
        return error;
 }
 
-static int do_rename(int olddfd, const char *oldname,
-                       int newdfd, const char *newname)
+SYSCALL_DEFINE4(renameat, int, olddfd, const char __user *, oldname,
+               int, newdfd, const char __user *, newname)
 {
-       int error = 0;
-       struct dentry * old_dir, * new_dir;
-       struct dentry * old_dentry, *new_dentry;
-       struct dentry * trap;
+       struct dentry *old_dir, *new_dir;
+       struct dentry *old_dentry, *new_dentry;
+       struct dentry *trap;
        struct nameidata oldnd, newnd;
+       char *from;
+       char *to;
+       int error;
 
-       error = do_path_lookup(olddfd, oldname, LOOKUP_PARENT, &oldnd);
+       error = user_path_parent(olddfd, oldname, &oldnd, &from);
        if (error)
                goto exit;
 
-       error = do_path_lookup(newdfd, newname, LOOKUP_PARENT, &newnd);
+       error = user_path_parent(newdfd, newname, &newnd, &to);
        if (error)
                goto exit1;
 
@@ -2780,6 +2660,10 @@ static int do_rename(int olddfd, const char *oldname,
        if (newnd.last_type != LAST_NORM)
                goto exit2;
 
+       oldnd.flags &= ~LOOKUP_PARENT;
+       newnd.flags &= ~LOOKUP_PARENT;
+       newnd.flags |= LOOKUP_RENAME_TARGET;
+
        trap = lock_rename(new_dir, old_dir);
 
        old_dentry = lookup_hash(&oldnd);
@@ -2814,8 +2698,13 @@ static int do_rename(int olddfd, const char *oldname,
        error = mnt_want_write(oldnd.path.mnt);
        if (error)
                goto exit5;
+       error = security_path_rename(&oldnd.path, old_dentry,
+                                    &newnd.path, new_dentry);
+       if (error)
+               goto exit6;
        error = vfs_rename(old_dir->d_inode, old_dentry,
                                   new_dir->d_inode, new_dentry);
+exit6:
        mnt_drop_write(oldnd.path.mnt);
 exit5:
        dput(new_dentry);
@@ -2825,33 +2714,15 @@ exit3:
        unlock_rename(new_dir, old_dir);
 exit2:
        path_put(&newnd.path);
+       putname(to);
 exit1:
        path_put(&oldnd.path);
-exit:
-       return error;
-}
-
-asmlinkage long sys_renameat(int olddfd, const char __user *oldname,
-                            int newdfd, const char __user *newname)
-{
-       int error;
-       char * from;
-       char * to;
-
-       from = getname(oldname);
-       if(IS_ERR(from))
-               return PTR_ERR(from);
-       to = getname(newname);
-       error = PTR_ERR(to);
-       if (!IS_ERR(to)) {
-               error = do_rename(olddfd, from, newdfd, to);
-               putname(to);
-       }
        putname(from);
+exit:
        return error;
 }
 
-asmlinkage long sys_rename(const char __user *oldname, const char __user *newname)
+SYSCALL_DEFINE2(rename, const char __user *, oldname, const char __user *, newname)
 {
        return sys_renameat(AT_FDCWD, oldname, AT_FDCWD, newname);
 }
@@ -2903,13 +2774,16 @@ int vfs_follow_link(struct nameidata *nd, const char *link)
 /* get the link contents into pagecache */
 static char *page_getlink(struct dentry * dentry, struct page **ppage)
 {
-       struct page * page;
+       char *kaddr;
+       struct page *page;
        struct address_space *mapping = dentry->d_inode->i_mapping;
        page = read_mapping_page(mapping, 0, NULL);
        if (IS_ERR(page))
                return (char*)page;
        *ppage = page;
-       return kmap(page);
+       kaddr = kmap(page);
+       nd_terminate_link(kaddr, dentry->d_inode->i_size, PAGE_SIZE - 1);
+       return kaddr;
 }
 
 int page_readlink(struct dentry *dentry, char __user *buffer, int buflen)
@@ -2941,18 +2815,23 @@ void page_put_link(struct dentry *dentry, struct nameidata *nd, void *cookie)
        }
 }
 
-int __page_symlink(struct inode *inode, const char *symname, int len,
-               gfp_t gfp_mask)
+/*
+ * The nofs argument instructs pagecache_write_begin to pass AOP_FLAG_NOFS
+ */
+int __page_symlink(struct inode *inode, const char *symname, int len, int nofs)
 {
        struct address_space *mapping = inode->i_mapping;
        struct page *page;
        void *fsdata;
        int err;
        char *kaddr;
+       unsigned int flags = AOP_FLAG_UNINTERRUPTIBLE;
+       if (nofs)
+               flags |= AOP_FLAG_NOFS;
 
 retry:
        err = pagecache_write_begin(NULL, mapping, 0, len-1,
-                               AOP_FLAG_UNINTERRUPTIBLE, &page, &fsdata);
+                               flags, &page, &fsdata);
        if (err)
                goto fail;
 
@@ -2976,7 +2855,7 @@ fail:
 int page_symlink(struct inode *inode, const char *symname, int len)
 {
        return __page_symlink(inode, symname, len,
-                       mapping_gfp_mask(inode->i_mapping));
+                       !(mapping_gfp_mask(inode->i_mapping) & __GFP_FS));
 }
 
 const struct inode_operations page_symlink_inode_operations = {
@@ -2985,8 +2864,7 @@ const struct inode_operations page_symlink_inode_operations = {
        .put_link       = page_put_link,
 };
 
-EXPORT_SYMBOL(__user_walk);
-EXPORT_SYMBOL(__user_walk_fd);
+EXPORT_SYMBOL(user_path_at);
 EXPORT_SYMBOL(follow_down);
 EXPORT_SYMBOL(follow_up);
 EXPORT_SYMBOL(get_write_access); /* binfmt_aout */
@@ -3000,9 +2878,9 @@ EXPORT_SYMBOL(__page_symlink);
 EXPORT_SYMBOL(page_symlink);
 EXPORT_SYMBOL(page_symlink_inode_operations);
 EXPORT_SYMBOL(path_lookup);
+EXPORT_SYMBOL(kern_path);
 EXPORT_SYMBOL(vfs_path_lookup);
-EXPORT_SYMBOL(permission);
-EXPORT_SYMBOL(vfs_permission);
+EXPORT_SYMBOL(inode_permission);
 EXPORT_SYMBOL(file_permission);
 EXPORT_SYMBOL(unlock_rename);
 EXPORT_SYMBOL(vfs_create);