12 files changed, 121 insertions, 141 deletions

diff --git a/fs/9p/vfs_inode.c b/fs/9p/vfs_inode.c
index 18f74ec4dce9..9d03d1ebca6f 100644
--- a/fs/9p/vfs_inode.c
+++ b/fs/9p/vfs_inode.c
@@ -1001,44 +1001,6 @@ done:
 }
 
 /**
- * v9fs_vfs_readlink - read a symlink's location
- * @dentry: dentry for symlink
- * @buffer: buffer to load symlink location into
- * @buflen: length of buffer
- *
- */
-
-static int v9fs_vfs_readlink(struct dentry *dentry, char __user * buffer,
-                             int buflen)
-{
-        int retval;
-        int ret;
-        char *link = __getname();
-
-        if (unlikely(!link))
-                return -ENOMEM;
-
-        if (buflen > PATH_MAX)
-                buflen = PATH_MAX;
-
-        P9_DPRINTK(P9_DEBUG_VFS, " dentry: %s (%p)\n", dentry->d_name.name,
-                                                                        dentry);
-
-        retval = v9fs_readlink(dentry, link, buflen);
-
-        if (retval > 0) {
-                if ((ret = copy_to_user(buffer, link, retval)) != 0) {
-                        P9_DPRINTK(P9_DEBUG_ERROR,
-                                        "problem copying to user: %d\n", ret);
-                        retval = ret;
-                }
-        }
-
-        __putname(link);
-        return retval;
-}
-
-/**
  * v9fs_vfs_follow_link - follow a symlink path
  * @dentry: dentry for symlink
  * @nd: nameidata
@@ -1230,7 +1192,6 @@ static const struct inode_operations v9fs_dir_inode_operations_ext = {
         .rmdir = v9fs_vfs_rmdir,
         .mknod = v9fs_vfs_mknod,
         .rename = v9fs_vfs_rename,
-        .readlink = v9fs_vfs_readlink,
         .getattr = v9fs_vfs_getattr,
         .setattr = v9fs_vfs_setattr,
 };
@@ -1253,7 +1214,7 @@ static const struct inode_operations v9fs_file_inode_operations = {
 };
 
 static const struct inode_operations v9fs_symlink_inode_operations = {
-        .readlink = v9fs_vfs_readlink,
+        .readlink = generic_readlink,
         .follow_link = v9fs_vfs_follow_link,
         .put_link = v9fs_vfs_put_link,
         .getattr = v9fs_vfs_getattr,
diff --git a/fs/cifs/cifs_dfs_ref.c b/fs/cifs/cifs_dfs_ref.c
index fea9e898c4ba..b44ce0a0711c 100644
--- a/fs/cifs/cifs_dfs_ref.c
+++ b/fs/cifs/cifs_dfs_ref.c
@@ -269,7 +269,7 @@ static int add_mount_helper(struct vfsmount *newmnt, struct nameidata *nd,
         int err;
 
         mntget(newmnt);
-        err = do_add_mount(newmnt, &nd->path, nd->path.mnt->mnt_flags, mntlist);
+        err = do_add_mount(newmnt, &nd->path, nd->path.mnt->mnt_flags | MNT_SHRINKABLE, mntlist);
         switch (err) {
         case 0:
                 path_put(&nd->path);
@@ -371,7 +371,6 @@ cifs_dfs_follow_mountpoint(struct dentry *dentry, struct nameidata *nd)
         if (IS_ERR(mnt))
                 goto out_err;
 
-        nd->path.mnt->mnt_flags |= MNT_SHRINKABLE;
         rc = add_mount_helper(mnt, nd, &cifs_dfs_automount_list);
 
 out:
diff --git a/fs/configfs/symlink.c b/fs/configfs/symlink.c
index c8afa6b1d91d..32a5f46b1157 100644
--- a/fs/configfs/symlink.c
+++ b/fs/configfs/symlink.c
@@ -121,8 +121,10 @@ static int get_target(const char *symname, struct path *path,
                                 ret = -ENOENT;
                                 path_put(path);
                         }
-                } else
+                } else {
                         ret = -EPERM;
+                        path_put(path);
+                }
         }
 
         return ret;
diff --git a/fs/ecryptfs/inode.c b/fs/ecryptfs/inode.c
index 429ca0b3ba08..7f8545032930 100644
--- a/fs/ecryptfs/inode.c
+++ b/fs/ecryptfs/inode.c
@@ -715,31 +715,31 @@ static void *ecryptfs_follow_link(struct dentry *dentry, struct nameidata *nd)
         /* Released in ecryptfs_put_link(); only release here on error */
         buf = kmalloc(len, GFP_KERNEL);
         if (!buf) {
-                rc = -ENOMEM;
+                buf = ERR_PTR(-ENOMEM);
                 goto out;
         }
         old_fs = get_fs();
         set_fs(get_ds());
         rc = dentry->d_inode->i_op->readlink(dentry, (char __user *)buf, len);
         set_fs(old_fs);
-        if (rc < 0)
-                goto out_free;
-        else
+        if (rc < 0) {
+                kfree(buf);
+                buf = ERR_PTR(rc);
+        } else
                 buf[rc] = '\0';
-        rc = 0;
-        nd_set_link(nd, buf);
-        goto out;
-out_free:
-        kfree(buf);
 out:
-        return ERR_PTR(rc);
+        nd_set_link(nd, buf);
+        return NULL;
 }
 
 static void
 ecryptfs_put_link(struct dentry *dentry, struct nameidata *nd, void *ptr)
 {
-        /* Free the char* */
-        kfree(nd_get_link(nd));
+        char *buf = nd_get_link(nd);
+        if (!IS_ERR(buf)) {
+                /* Free the char* */
+                kfree(buf);
+        }
 }
 
 /**
diff --git a/fs/fcntl.c b/fs/fcntl.c
index 2cf93ec40a67..97e01dc0d95f 100644
--- a/fs/fcntl.c
+++ b/fs/fcntl.c
@@ -618,60 +618,90 @@ static DEFINE_RWLOCK(fasync_lock);
 static struct kmem_cache *fasync_cache __read_mostly;
 
 /*
- * fasync_helper() is used by almost all character device drivers
- * to set up the fasync queue. It returns negative on error, 0 if it did
- * no changes and positive if it added/deleted the entry.
+ * Remove a fasync entry. If successfully removed, return
+ * positive and clear the FASYNC flag. If no entry exists,
+ * do nothing and return 0.
+ *
+ * NOTE! It is very important that the FASYNC flag always
+ * match the state "is the filp on a fasync list".
+ *
+ * We always take the 'filp->f_lock', in since fasync_lock
+ * needs to be irq-safe.
  */
-int fasync_helper(int fd, struct file * filp, int on, struct fasync_struct **fapp)
+static int fasync_remove_entry(struct file *filp, struct fasync_struct **fapp)
 {
         struct fasync_struct *fa, **fp;
-        struct fasync_struct *new = NULL;
         int result = 0;
 
-        if (on) {
-                new = kmem_cache_alloc(fasync_cache, GFP_KERNEL);
-                if (!new)
-                        return -ENOMEM;
+        spin_lock(&filp->f_lock);
+        write_lock_irq(&fasync_lock);
+        for (fp = fapp; (fa = *fp) != NULL; fp = &fa->fa_next) {
+                if (fa->fa_file != filp)
+                        continue;
+                *fp = fa->fa_next;
+                kmem_cache_free(fasync_cache, fa);
+                filp->f_flags &= ~FASYNC;
+                result = 1;
+                break;
         }
+        write_unlock_irq(&fasync_lock);
+        spin_unlock(&filp->f_lock);
+        return result;
+}
+
+/*
+ * Add a fasync entry. Return negative on error, positive if
+ * added, and zero if did nothing but change an existing one.
+ *
+ * NOTE! It is very important that the FASYNC flag always
+ * match the state "is the filp on a fasync list".
+ */
+static int fasync_add_entry(int fd, struct file *filp, struct fasync_struct **fapp)
+{
+        struct fasync_struct *new, *fa, **fp;
+        int result = 0;
+
+        new = kmem_cache_alloc(fasync_cache, GFP_KERNEL);
+        if (!new)
+                return -ENOMEM;
 
-        /*
-         * We need to take f_lock first since it's not an IRQ-safe
-         * lock.
-         */
         spin_lock(&filp->f_lock);
         write_lock_irq(&fasync_lock);
         for (fp = fapp; (fa = *fp) != NULL; fp = &fa->fa_next) {
-                if (fa->fa_file == filp) {
-                        if(on) {
-                                fa->fa_fd = fd;
-                                kmem_cache_free(fasync_cache, new);
-                        } else {
-                                *fp = fa->fa_next;
-                                kmem_cache_free(fasync_cache, fa);
-                                result = 1;
-                        }
-                        goto out;
-                }
+                if (fa->fa_file != filp)
+                        continue;
+                fa->fa_fd = fd;
+                kmem_cache_free(fasync_cache, new);
+                goto out;
         }
 
-        if (on) {
-                new->magic = FASYNC_MAGIC;
-                new->fa_file = filp;
-                new->fa_fd = fd;
-                new->fa_next = *fapp;
-                *fapp = new;
-                result = 1;
-        }
+        new->magic = FASYNC_MAGIC;
+        new->fa_file = filp;
+        new->fa_fd = fd;
+        new->fa_next = *fapp;
+        *fapp = new;
+        result = 1;
+        filp->f_flags |= FASYNC;
+
 out:
-        if (on)
-                filp->f_flags |= FASYNC;
-        else
-                filp->f_flags &= ~FASYNC;
         write_unlock_irq(&fasync_lock);
         spin_unlock(&filp->f_lock);
         return result;
 }
 
+/*
+ * fasync_helper() is used by almost all character device drivers
+ * to set up the fasync queue, and for regular files by the file
+ * lease code. It returns negative on error, 0 if it did no changes
+ * and positive if it added/deleted the entry.
+ */
+int fasync_helper(int fd, struct file * filp, int on, struct fasync_struct **fapp)
+{
+        if (!on)
+                return fasync_remove_entry(filp, fapp);
+        return fasync_add_entry(fd, filp, fapp);
+}
+
 EXPORT_SYMBOL(fasync_helper);
 
 void __kill_fasync(struct fasync_struct *fa, int sig, int band)
diff --git a/fs/hppfs/hppfs.c b/fs/hppfs/hppfs.c
index a5089a6dd67a..7239efc690d8 100644
--- a/fs/hppfs/hppfs.c
+++ b/fs/hppfs/hppfs.c
@@ -646,22 +646,27 @@ static const struct super_operations hppfs_sbops = {
 static int hppfs_readlink(struct dentry *dentry, char __user *buffer,
                           int buflen)
 {
-        struct dentry *proc_dentry;
-
-        proc_dentry = HPPFS_I(dentry->d_inode)->proc_dentry;
+        struct dentry *proc_dentry = HPPFS_I(dentry->d_inode)->proc_dentry;
         return proc_dentry->d_inode->i_op->readlink(proc_dentry, buffer,
                                                     buflen);
 }
 
 static void *hppfs_follow_link(struct dentry *dentry, struct nameidata *nd)
 {
-        struct dentry *proc_dentry;
-
-        proc_dentry = HPPFS_I(dentry->d_inode)->proc_dentry;
+        struct dentry *proc_dentry = HPPFS_I(dentry->d_inode)->proc_dentry;
 
         return proc_dentry->d_inode->i_op->follow_link(proc_dentry, nd);
 }
 
+static void hppfs_put_link(struct dentry *dentry, struct nameidata *nd,
+                           void *cookie)
+{
+        struct dentry *proc_dentry = HPPFS_I(dentry->d_inode)->proc_dentry;
+
+        if (proc_dentry->d_inode->i_op->put_link)
+                proc_dentry->d_inode->i_op->put_link(proc_dentry, nd, cookie);
+}
+
 static const struct inode_operations hppfs_dir_iops = {
         .lookup         = hppfs_lookup,
 };
@@ -669,6 +674,7 @@ static const struct inode_operations hppfs_dir_iops = {
 static const struct inode_operations hppfs_link_iops = {
         .readlink       = hppfs_readlink,
         .follow_link    = hppfs_follow_link,
+        .put_link       = hppfs_put_link,
 };
 
 static struct inode *get_inode(struct super_block *sb, struct dentry *dentry)
diff --git a/fs/namei.c b/fs/namei.c
index b55440baf7ab..94a5e60779f9 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -561,6 +561,7 @@ static __always_inline int __do_follow_link(struct path *path, struct nameidata
                 dget(dentry);
         }
         mntget(path->mnt);
+        nd->last_type = LAST_BIND;
         cookie = dentry->d_inode->i_op->follow_link(dentry, nd);
         error = PTR_ERR(cookie);
         if (!IS_ERR(cookie)) {
@@ -1603,11 +1604,12 @@ struct file *do_filp_open(int dfd, const char *pathname,
         struct file *filp;
         struct nameidata nd;
         int error;
-        struct path path, save;
+        struct path path;
         struct dentry *dir;
         int count = 0;
         int will_truncate;
         int flag = open_to_namei_flags(open_flag);
+        int force_reval = 0;
 
         /*
          * O_SYNC is implemented as __O_SYNC|O_DSYNC.  As many places only
@@ -1619,7 +1621,7 @@ struct file *do_filp_open(int dfd, const char *pathname,
                 open_flag |= O_DSYNC;
 
         if (!acc_mode)
-                acc_mode = MAY_OPEN | ACC_MODE(flag);
+                acc_mode = MAY_OPEN | ACC_MODE(open_flag);
 
         /* O_TRUNC implies we need access checks for write permissions */
         if (flag & O_TRUNC)
@@ -1659,9 +1661,12 @@ struct file *do_filp_open(int dfd, const char *pathname,
         /*
          * Create - we need to know the parent.
          */
+reval:
         error = path_init(dfd, pathname, LOOKUP_PARENT, &nd);
         if (error)
                 return ERR_PTR(error);
+        if (force_reval)
+                nd.flags |= LOOKUP_REVAL;
         error = path_walk(pathname, &nd);
         if (error) {
                 if (nd.root.mnt)
@@ -1853,17 +1858,7 @@ 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
@@ -1873,6 +1868,10 @@ do_link:
                 release_open_intent(&nd);
                 if (nd.root.mnt)
                         path_put(&nd.root);
+                if (error == -ESTALE && !force_reval) {
+                        force_reval = 1;
+                        goto reval;
+                }
                 return ERR_PTR(error);
         }
         nd.flags &= ~LOOKUP_PARENT;
diff --git a/fs/namespace.c b/fs/namespace.c
index 7d70d63ceb29..c768f733c8d6 100644
--- a/fs/namespace.c
+++ b/fs/namespace.c
@@ -965,10 +965,12 @@ EXPORT_SYMBOL(may_umount_tree);
 int may_umount(struct vfsmount *mnt)
 {
         int ret = 1;
+        down_read(&namespace_sem);
         spin_lock(&vfsmount_lock);
         if (propagate_mount_busy(mnt, 2))
                 ret = 0;
         spin_unlock(&vfsmount_lock);
+        up_read(&namespace_sem);
         return ret;
 }
 
@@ -1352,12 +1354,12 @@ static int attach_recursive_mnt(struct vfsmount *source_mnt,
         if (err)
                 goto out_cleanup_ids;
 
+        spin_lock(&vfsmount_lock);
+
         if (IS_MNT_SHARED(dest_mnt)) {
                 for (p = source_mnt; p; p = next_mnt(p, source_mnt))
                         set_mnt_shared(p);
         }
-
-        spin_lock(&vfsmount_lock);
         if (parent_path) {
                 detach_mnt(source_mnt, parent_path);
                 attach_mnt(source_mnt, path);
@@ -1534,8 +1536,12 @@ static int do_remount(struct path *path, int flags, int mnt_flags,
                 err = change_mount_flags(path->mnt, flags);
         else
                 err = do_remount_sb(sb, flags, data, 0);
-        if (!err)
+        if (!err) {
+                spin_lock(&vfsmount_lock);
+                mnt_flags |= path->mnt->mnt_flags & MNT_PNODE_MASK;
                 path->mnt->mnt_flags = mnt_flags;
+                spin_unlock(&vfsmount_lock);
+        }
         up_write(&sb->s_umount);
         if (!err) {
                 security_sb_post_remount(path->mnt, flags, data);
@@ -1665,6 +1671,8 @@ int do_add_mount(struct vfsmount *newmnt, struct path *path,
 {
         int err;
 
+        mnt_flags &= ~(MNT_SHARED | MNT_WRITE_HOLD);
+
         down_write(&namespace_sem);
         /* Something was mounted here while we slept */
         while (d_mountpoint(path->dentry) &&
diff --git a/fs/notify/inotify/inotify_fsnotify.c b/fs/notify/inotify/inotify_fsnotify.c
index c9ee67b442e1..1afb0a10229f 100644
--- a/fs/notify/inotify/inotify_fsnotify.c
+++ b/fs/notify/inotify/inotify_fsnotify.c
@@ -121,7 +121,7 @@ static int idr_callback(int id, void *p, void *data)
         if (warned)
                 return 0;
 
-        warned = false;
+        warned = true;
         entry = p;
         ientry = container_of(entry, struct inotify_inode_mark_entry, fsn_entry);
 
diff --git a/fs/notify/inotify/inotify_user.c b/fs/notify/inotify/inotify_user.c
index 8271cf05c957..a94e8bd8eb1f 100644
--- a/fs/notify/inotify/inotify_user.c
+++ b/fs/notify/inotify/inotify_user.c
@@ -552,7 +552,7 @@ retry:
 
         spin_lock(&group->inotify_data.idr_lock);
         ret = idr_get_new_above(&group->inotify_data.idr, &tmp_ientry->fsn_entry,
-                                group->inotify_data.last_wd,
+                                group->inotify_data.last_wd+1,
                                 &tmp_ientry->wd);
         spin_unlock(&group->inotify_data.idr_lock);
         if (ret) {
@@ -632,7 +632,7 @@ static struct fsnotify_group *inotify_new_group(struct user_struct *user, unsign
 
         spin_lock_init(&group->inotify_data.idr_lock);
         idr_init(&group->inotify_data.idr);
-        group->inotify_data.last_wd = 1;
+        group->inotify_data.last_wd = 0;
         group->inotify_data.user = user;
         group->inotify_data.fa = NULL;
 
diff --git a/fs/proc/base.c b/fs/proc/base.c
index 18d5cc62d8ed..e42bbd843ed1 100644
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -1419,7 +1419,6 @@ static void *proc_pid_follow_link(struct dentry *dentry, struct nameidata *nd)
                 goto out;
 
         error = PROC_I(inode)->op.proc_get_link(inode, &nd->path);
-        nd->last_type = LAST_BIND;
 out:
         return ERR_PTR(error);
 }
diff --git a/fs/ramfs/file-nommu.c b/fs/ramfs/file-nommu.c
index 2efc57173fd7..1739a4aba25f 100644
--- a/fs/ramfs/file-nommu.c
+++ b/fs/ramfs/file-nommu.c
@@ -123,30 +123,6 @@ add_error:
 
 /*****************************************************************************/
 /*
- * check that file shrinkage doesn't leave any VMAs dangling in midair
- */
-static int ramfs_nommu_check_mappings(struct inode *inode,
-                                      size_t newsize, size_t size)
-{
-        struct vm_area_struct *vma;
-        struct prio_tree_iter iter;
-
-        /* search for VMAs that fall within the dead zone */
-        vma_prio_tree_foreach(vma, &iter, &inode->i_mapping->i_mmap,
-                              newsize >> PAGE_SHIFT,
-                              (size + PAGE_SIZE - 1) >> PAGE_SHIFT
-                              ) {
-                /* found one - only interested if it's shared out of the page
-                 * cache */
-                if (vma->vm_flags & VM_SHARED)
-                        return -ETXTBSY; /* not quite true, but near enough */
-        }
-
-        return 0;
-}
-
-/*****************************************************************************/
-/*
  *
  */
 static int ramfs_nommu_resize(struct inode *inode, loff_t newsize, loff_t size)
@@ -164,7 +140,7 @@ static int ramfs_nommu_resize(struct inode *inode, loff_t newsize, loff_t size)
 
         /* check that a decrease in size doesn't cut off any shared mappings */
         if (newsize < size) {
-                ret = ramfs_nommu_check_mappings(inode, newsize, size);
+                ret = nommu_shrink_inode_mappings(inode, size, newsize);
                 if (ret < 0)
                         return ret;
         }