Merge branch 'bugfixes' of git://git.linux-nfs.org/projects/trondmy/nfs-2.6

* 'bugfixes' of git://git.linux-nfs.org/projects/trondmy/nfs-2.6:
  NFS: Fix panic after nfs_umount()
  nfs: remove extraneous and problematic calls to nfs_clear_request
  nfs: kernel should return EPROTONOSUPPORT when not support NFSv4
  NFS: Fix fcntl F_GETLK not reporting some conflicts
  nfs: Discard ACL cache on mode update
  NFS: Readdir cleanups
  NFS: nfs_readdir_search_for_cookie() don't mark as eof if cookie not found
  NFS: Fix a memory leak in nfs_readdir
  Call the filesystem back whenever a page is removed from the page cache
  NFS: Ensure we use the correct cookie in nfs_readdir_xdr_filler

17 files changed, 85 insertions, 52 deletions

diff --git a/Documentation/filesystems/Locking b/Documentation/filesystems/Locking
index a91f30890011..b6426f15b4ae 100644
--- a/Documentation/filesystems/Locking
+++ b/Documentation/filesystems/Locking
@@ -173,12 +173,13 @@ prototypes:
         sector_t (*bmap)(struct address_space *, sector_t);
         int (*invalidatepage) (struct page *, unsigned long);
         int (*releasepage) (struct page *, int);
+        void (*freepage)(struct page *);
         int (*direct_IO)(int, struct kiocb *, const struct iovec *iov,
                         loff_t offset, unsigned long nr_segs);
         int (*launder_page) (struct page *);
 
 locking rules:
-        All except set_page_dirty may block
+        All except set_page_dirty and freepage may block
 
                         BKL     PageLocked(page)        i_mutex
 writepage:              no      yes, unlocks (see below)
@@ -193,6 +194,7 @@ perform_write:		no	n/a			yes
 bmap:                   no
 invalidatepage:         no      yes
 releasepage:            no      yes
+freepage:               no      yes
 direct_IO:              no
 launder_page:           no      yes
 
@@ -288,6 +290,9 @@ buffers from the page in preparation for freeing it.  It returns zero to
 indicate that the buffers are (or may be) freeable.  If ->releasepage is zero,
 the kernel assumes that the fs has no private interest in the buffers.
 
+        ->freepage() is called when the kernel is done dropping the page
+from the page cache.
+
         ->launder_page() may be called prior to releasing a page if
 it is still found to be dirty. It returns zero if the page was successfully
 cleaned, or an error value if not. Note that in order to prevent the page
diff --git a/Documentation/filesystems/vfs.txt b/Documentation/filesystems/vfs.txt
index 55c28b79d8dc..20899e095e7e 100644
--- a/Documentation/filesystems/vfs.txt
+++ b/Documentation/filesystems/vfs.txt
@@ -534,6 +534,7 @@ struct address_space_operations {
         sector_t (*bmap)(struct address_space *, sector_t);
         int (*invalidatepage) (struct page *, unsigned long);
         int (*releasepage) (struct page *, int);
+        void (*freepage)(struct page *);
         ssize_t (*direct_IO)(int, struct kiocb *, const struct iovec *iov,
                         loff_t offset, unsigned long nr_segs);
         struct page* (*get_xip_page)(struct address_space *, sector_t,
@@ -678,6 +679,12 @@ struct address_space_operations {
         need to ensure this.  Possibly it can clear the PageUptodate
         bit if it cannot free private data yet.
 
+  freepage: freepage is called once the page is no longer visible in
+        the page cache in order to allow the cleanup of any private
+        data. Since it may be called by the memory reclaimer, it
+        should not assume that the original address_space mapping still
+        exists, and it should not block.
+
   direct_IO: called by the generic read/write routines to perform
         direct_IO - that is IO requests which bypass the page cache
         and transfer data directly between the storage and the
diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c
index f0a384e2ae63..996dd8989a91 100644
--- a/fs/nfs/dir.c
+++ b/fs/nfs/dir.c
@@ -57,7 +57,7 @@ static int nfs_rename(struct inode *, struct dentry *,
                       struct inode *, struct dentry *);
 static int nfs_fsync_dir(struct file *, int);
 static loff_t nfs_llseek_dir(struct file *, loff_t, int);
-static int nfs_readdir_clear_array(struct page*, gfp_t);
+static void nfs_readdir_clear_array(struct page*);
 
 const struct file_operations nfs_dir_operations = {
         .llseek         = nfs_llseek_dir,
@@ -83,8 +83,8 @@ const struct inode_operations nfs_dir_inode_operations = {
         .setattr        = nfs_setattr,
 };
 
-const struct address_space_operations nfs_dir_addr_space_ops = {
-        .releasepage = nfs_readdir_clear_array,
+const struct address_space_operations nfs_dir_aops = {
+        .freepage = nfs_readdir_clear_array,
 };
 
 #ifdef CONFIG_NFS_V3
@@ -178,6 +178,7 @@ typedef struct {
         struct page     *page;
         unsigned long   page_index;
         u64             *dir_cookie;
+        u64             last_cookie;
         loff_t          current_index;
         decode_dirent_t decode;
 
@@ -213,17 +214,15 @@ void nfs_readdir_release_array(struct page *page)
  * we are freeing strings created by nfs_add_to_readdir_array()
  */
 static
-int nfs_readdir_clear_array(struct page *page, gfp_t mask)
+void nfs_readdir_clear_array(struct page *page)
 {
-        struct nfs_cache_array *array = nfs_readdir_get_array(page);
+        struct nfs_cache_array *array;
         int i;
 
-        if (IS_ERR(array))
-                return PTR_ERR(array);
+        array = kmap_atomic(page, KM_USER0);
         for (i = 0; i < array->size; i++)
                 kfree(array->array[i].string.name);
-        nfs_readdir_release_array(page);
-        return 0;
+        kunmap_atomic(array, KM_USER0);
 }
 
 /*
@@ -272,7 +271,7 @@ int nfs_readdir_add_to_array(struct nfs_entry *entry, struct page *page)
                 goto out;
         array->last_cookie = entry->cookie;
         array->size++;
-        if (entry->eof == 1)
+        if (entry->eof != 0)
                 array->eof_index = array->size;
 out:
         nfs_readdir_release_array(page);
@@ -312,15 +311,14 @@ int nfs_readdir_search_for_cookie(struct nfs_cache_array *array, nfs_readdir_des
         for (i = 0; i < array->size; i++) {
                 if (array->array[i].cookie == *desc->dir_cookie) {
                         desc->cache_entry_index = i;
-                        status = 0;
-                        goto out;
+                        return 0;
                 }
         }
-        if (i == array->eof_index) {
-                desc->eof = 1;
+        if (array->eof_index >= 0) {
                 status = -EBADCOOKIE;
+                if (*desc->dir_cookie == array->last_cookie)
+                        desc->eof = 1;
         }
-out:
         return status;
 }
 
@@ -328,10 +326,7 @@ static
 int nfs_readdir_search_array(nfs_readdir_descriptor_t *desc)
 {
         struct nfs_cache_array *array;
-        int status = -EBADCOOKIE;
-
-        if (desc->dir_cookie == NULL)
-                goto out;
+        int status;
 
         array = nfs_readdir_get_array(desc->page);
         if (IS_ERR(array)) {
@@ -344,6 +339,10 @@ int nfs_readdir_search_array(nfs_readdir_descriptor_t *desc)
         else
                 status = nfs_readdir_search_for_cookie(array, desc);
 
+        if (status == -EAGAIN) {
+                desc->last_cookie = array->last_cookie;
+                desc->page_index++;
+        }
         nfs_readdir_release_array(desc->page);
 out:
         return status;
@@ -490,7 +489,7 @@ int nfs_readdir_page_filler(nfs_readdir_descriptor_t *desc, struct nfs_entry *en
 
                 count++;
 
-                if (desc->plus == 1)
+                if (desc->plus != 0)
                         nfs_prime_dcache(desc->file->f_path.dentry, entry);
 
                 status = nfs_readdir_add_to_array(entry, page);
@@ -498,7 +497,7 @@ int nfs_readdir_page_filler(nfs_readdir_descriptor_t *desc, struct nfs_entry *en
                         break;
         } while (!entry->eof);
 
-        if (count == 0 || (status == -EBADCOOKIE && entry->eof == 1)) {
+        if (count == 0 || (status == -EBADCOOKIE && entry->eof != 0)) {
                 array = nfs_readdir_get_array(page);
                 if (!IS_ERR(array)) {
                         array->eof_index = array->size;
@@ -563,7 +562,7 @@ int nfs_readdir_xdr_to_array(nfs_readdir_descriptor_t *desc, struct page *page,
         unsigned int array_size = ARRAY_SIZE(pages);
 
         entry.prev_cookie = 0;
-        entry.cookie = *desc->dir_cookie;
+        entry.cookie = desc->last_cookie;
         entry.eof = 0;
         entry.fh = nfs_alloc_fhandle();
         entry.fattr = nfs_alloc_fattr();
@@ -636,6 +635,8 @@ int nfs_readdir_filler(nfs_readdir_descriptor_t *desc, struct page* page)
 static
 void cache_page_release(nfs_readdir_descriptor_t *desc)
 {
+        if (!desc->page->mapping)
+                nfs_readdir_clear_array(desc->page);
         page_cache_release(desc->page);
         desc->page = NULL;
 }
@@ -660,9 +661,8 @@ int find_cache_page(nfs_readdir_descriptor_t *desc)
                 return PTR_ERR(desc->page);
 
         res = nfs_readdir_search_array(desc);
-        if (res == 0)
-                return 0;
-        cache_page_release(desc);
+        if (res != 0)
+                cache_page_release(desc);
         return res;
 }
 
@@ -672,22 +672,16 @@ int readdir_search_pagecache(nfs_readdir_descriptor_t *desc)
 {
         int res;
 
-        if (desc->page_index == 0)
+        if (desc->page_index == 0) {
                 desc->current_index = 0;
-        while (1) {
-                res = find_cache_page(desc);
-                if (res != -EAGAIN)
-                        break;
-                desc->page_index++;
+                desc->last_cookie = 0;
         }
+        do {
+                res = find_cache_page(desc);
+        } while (res == -EAGAIN);
         return res;
 }
 
-static inline unsigned int dt_type(struct inode *inode)
-{
-        return (inode->i_mode >> 12) & 15;
-}
-
 /*
  * Once we've found the start of the dirent within a page: fill 'er up...
  */
@@ -717,13 +711,12 @@ int nfs_do_filldir(nfs_readdir_descriptor_t *desc, void *dirent,
                         break;
                 }
                 file->f_pos++;
-                desc->cache_entry_index = i;
                 if (i < (array->size-1))
                         *desc->dir_cookie = array->array[i+1].cookie;
                 else
                         *desc->dir_cookie = array->last_cookie;
         }
-        if (i == array->eof_index)
+        if (array->eof_index >= 0)
                 desc->eof = 1;
 
         nfs_readdir_release_array(desc->page);
@@ -764,6 +757,7 @@ int uncached_readdir(nfs_readdir_descriptor_t *desc, void *dirent,
         }
 
         desc->page_index = 0;
+        desc->last_cookie = *desc->dir_cookie;
         desc->page = page;
 
         status = nfs_readdir_xdr_to_array(desc, page, inode);
@@ -791,7 +785,7 @@ static int nfs_readdir(struct file *filp, void *dirent, filldir_t filldir)
         struct inode    *inode = dentry->d_inode;
         nfs_readdir_descriptor_t my_desc,
                         *desc = &my_desc;
-        int res = -ENOMEM;
+        int res;
 
         dfprintk(FILE, "NFS: readdir(%s/%s) starting at cookie %llu\n",
                         dentry->d_parent->d_name.name, dentry->d_name.name,
@@ -816,7 +810,7 @@ static int nfs_readdir(struct file *filp, void *dirent, filldir_t filldir)
         if (res < 0)
                 goto out;
 
-        while (desc->eof != 1) {
+        do {
                 res = readdir_search_pagecache(desc);
 
                 if (res == -EBADCOOKIE) {
@@ -844,7 +838,7 @@ static int nfs_readdir(struct file *filp, void *dirent, filldir_t filldir)
                 res = nfs_do_filldir(desc, dirent, filldir);
                 if (res < 0)
                         break;
-        }
+        } while (!desc->eof);
 out:
         nfs_unblock_sillyrename(dentry);
         if (res > 0)
diff --git a/fs/nfs/file.c b/fs/nfs/file.c
index 60677f9f1311..7bf029ef4084 100644
--- a/fs/nfs/file.c
+++ b/fs/nfs/file.c
@@ -693,6 +693,7 @@ do_getlk(struct file *filp, int cmd, struct file_lock *fl, int is_local)
 {
         struct inode *inode = filp->f_mapping->host;
         int status = 0;
+        unsigned int saved_type = fl->fl_type;
 
         /* Try local locking first */
         posix_test_lock(filp, fl);
@@ -700,6 +701,7 @@ do_getlk(struct file *filp, int cmd, struct file_lock *fl, int is_local)
                 /* found a conflict */
                 goto out;
         }
+        fl->fl_type = saved_type;
 
         if (nfs_have_delegation(inode, FMODE_READ))
                 goto out_noconflict;
diff --git a/fs/nfs/inode.c b/fs/nfs/inode.c
index 314f57164602..e67e31c73416 100644
--- a/fs/nfs/inode.c
+++ b/fs/nfs/inode.c
@@ -289,6 +289,7 @@ nfs_fhget(struct super_block *sb, struct nfs_fh *fh, struct nfs_fattr *fattr)
                 } else if (S_ISDIR(inode->i_mode)) {
                         inode->i_op = NFS_SB(sb)->nfs_client->rpc_ops->dir_inode_ops;
                         inode->i_fop = &nfs_dir_operations;
+                        inode->i_data.a_ops = &nfs_dir_aops;
                         if (nfs_server_capable(inode, NFS_CAP_READDIRPLUS))
                                 set_bit(NFS_INO_ADVISE_RDPLUS, &NFS_I(inode)->flags);
                         /* Deal with crossing mountpoints */
diff --git a/fs/nfs/mount_clnt.c b/fs/nfs/mount_clnt.c
index eceafe74f473..4f981f1f6689 100644
--- a/fs/nfs/mount_clnt.c
+++ b/fs/nfs/mount_clnt.c
@@ -505,13 +505,13 @@ static struct rpc_procinfo mnt3_procedures[] = {
 
 static struct rpc_version mnt_version1 = {
         .number         = 1,
-        .nrprocs        = 2,
+        .nrprocs        = ARRAY_SIZE(mnt_procedures),
         .procs          = mnt_procedures,
 };
 
 static struct rpc_version mnt_version3 = {
         .number         = 3,
-        .nrprocs        = 2,
+        .nrprocs        = ARRAY_SIZE(mnt3_procedures),
         .procs          = mnt3_procedures,
 };
 
diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index 6a653ffd8e4e..4435e5e1f904 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -3361,6 +3361,8 @@ static ssize_t nfs4_proc_get_acl(struct inode *inode, void *buf, size_t buflen)
         ret = nfs_revalidate_inode(server, inode);
         if (ret < 0)
                 return ret;
+        if (NFS_I(inode)->cache_validity & NFS_INO_INVALID_ACL)
+                nfs_zap_acl_cache(inode);
         ret = nfs4_read_cached_acl(inode, buf, buflen);
         if (ret != -ENOENT)
                 return ret;
@@ -3389,6 +3391,13 @@ static int __nfs4_proc_set_acl(struct inode *inode, const void *buf, size_t bufl
         nfs_inode_return_delegation(inode);
         buf_to_pages(buf, buflen, arg.acl_pages, &arg.acl_pgbase);
         ret = nfs4_call_sync(server, &msg, &arg, &res, 1);
+        /*
+         * Acl update can result in inode attribute update.
+         * so mark the attribute cache invalid.
+         */
+        spin_lock(&inode->i_lock);
+        NFS_I(inode)->cache_validity |= NFS_INO_INVALID_ATTR;
+        spin_unlock(&inode->i_lock);
         nfs_access_zap_cache(inode);
         nfs_zap_acl_cache(inode);
         return ret;
diff --git a/fs/nfs/pagelist.c b/fs/nfs/pagelist.c
index 137b549e63db..b68536cc9046 100644
--- a/fs/nfs/pagelist.c
+++ b/fs/nfs/pagelist.c
@@ -115,7 +115,7 @@ int nfs_set_page_tag_locked(struct nfs_page *req)
 {
         if (!nfs_lock_request_dontget(req))
                 return 0;
-        if (req->wb_page != NULL)
+        if (test_bit(PG_MAPPED, &req->wb_flags))
                 radix_tree_tag_set(&NFS_I(req->wb_context->path.dentry->d_inode)->nfs_page_tree, req->wb_index, NFS_PAGE_TAG_LOCKED);
         return 1;
 }
@@ -125,7 +125,7 @@ int nfs_set_page_tag_locked(struct nfs_page *req)
  */
 void nfs_clear_page_tag_locked(struct nfs_page *req)
 {
-        if (req->wb_page != NULL) {
+        if (test_bit(PG_MAPPED, &req->wb_flags)) {
                 struct inode *inode = req->wb_context->path.dentry->d_inode;
                 struct nfs_inode *nfsi = NFS_I(inode);
 
diff --git a/fs/nfs/read.c b/fs/nfs/read.c
index e4b62c6f5a6e..aedcaa7f291f 100644
--- a/fs/nfs/read.c
+++ b/fs/nfs/read.c
@@ -152,7 +152,6 @@ static void nfs_readpage_release(struct nfs_page *req)
                         (long long)NFS_FILEID(req->wb_context->path.dentry->d_inode),
                         req->wb_bytes,
                         (long long)req_offset(req));
-        nfs_clear_request(req);
         nfs_release_request(req);
 }
 
diff --git a/fs/nfs/super.c b/fs/nfs/super.c
index 3c045044fca2..4100630c9a5b 100644
--- a/fs/nfs/super.c
+++ b/fs/nfs/super.c
@@ -1069,12 +1069,10 @@ static int nfs_parse_mount_options(char *raw,
                         mnt->flags |= NFS_MOUNT_VER3;
                         mnt->version = 3;
                         break;
-#ifdef CONFIG_NFS_V4
                 case Opt_v4:
                         mnt->flags &= ~NFS_MOUNT_VER3;
                         mnt->version = 4;
                         break;
-#endif
                 case Opt_udp:
                         mnt->flags &= ~NFS_MOUNT_TCP;
                         mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
@@ -1286,12 +1284,10 @@ static int nfs_parse_mount_options(char *raw,
                                 mnt->flags |= NFS_MOUNT_VER3;
                                 mnt->version = 3;
                                 break;
-#ifdef CONFIG_NFS_V4
                         case NFS4_VERSION:
                                 mnt->flags &= ~NFS_MOUNT_VER3;
                                 mnt->version = 4;
                                 break;
-#endif
                         default:
                                 goto out_invalid_value;
                         }
diff --git a/fs/nfs/write.c b/fs/nfs/write.c
index 4c14c17a5276..10d648ea128b 100644
--- a/fs/nfs/write.c
+++ b/fs/nfs/write.c
@@ -390,6 +390,7 @@ static int nfs_inode_add_request(struct inode *inode, struct nfs_page *req)
                 if (nfs_have_delegation(inode, FMODE_WRITE))
                         nfsi->change_attr++;
         }
+        set_bit(PG_MAPPED, &req->wb_flags);
         SetPagePrivate(req->wb_page);
         set_page_private(req->wb_page, (unsigned long)req);
         nfsi->npages++;
@@ -415,6 +416,7 @@ static void nfs_inode_remove_request(struct nfs_page *req)
         spin_lock(&inode->i_lock);
         set_page_private(req->wb_page, 0);
         ClearPagePrivate(req->wb_page);
+        clear_bit(PG_MAPPED, &req->wb_flags);
         radix_tree_delete(&nfsi->nfs_page_tree, req->wb_index);
         nfsi->npages--;
         if (!nfsi->npages) {
@@ -422,7 +424,6 @@ static void nfs_inode_remove_request(struct nfs_page *req)
                 iput(inode);
         } else
                 spin_unlock(&inode->i_lock);
-        nfs_clear_request(req);
         nfs_release_request(req);
 }
 
diff --git a/include/linux/fs.h b/include/linux/fs.h
index c9e06cc70dad..090f0eacde29 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -602,6 +602,7 @@ struct address_space_operations {
         sector_t (*bmap)(struct address_space *, sector_t);
         void (*invalidatepage) (struct page *, unsigned long);
         int (*releasepage) (struct page *, gfp_t);
+        void (*freepage)(struct page *);
         ssize_t (*direct_IO)(int, struct kiocb *, const struct iovec *iov,
                         loff_t offset, unsigned long nr_segs);
         int (*get_xip_mem)(struct address_space *, pgoff_t, int,
diff --git a/include/linux/nfs_fs.h b/include/linux/nfs_fs.h
index c66fdb7d6998..29d504d5d1c3 100644
--- a/include/linux/nfs_fs.h
+++ b/include/linux/nfs_fs.h
@@ -401,6 +401,7 @@ extern const struct inode_operations nfs3_file_inode_operations;
 #endif /* CONFIG_NFS_V3 */
 extern const struct file_operations nfs_file_operations;
 extern const struct address_space_operations nfs_file_aops;
+extern const struct address_space_operations nfs_dir_aops;
 
 static inline struct nfs_open_context *nfs_file_open_context(struct file *filp)
 {
diff --git a/include/linux/nfs_page.h b/include/linux/nfs_page.h
index f8b60e7f4c44..d55cee73f634 100644
--- a/include/linux/nfs_page.h
+++ b/include/linux/nfs_page.h
@@ -29,6 +29,7 @@
  */
 enum {
         PG_BUSY = 0,
+        PG_MAPPED,
         PG_CLEAN,
         PG_NEED_COMMIT,
         PG_NEED_RESCHED,
diff --git a/mm/filemap.c b/mm/filemap.c
index ea89840fc65f..6b9aee20f242 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -143,13 +143,18 @@ void __remove_from_page_cache(struct page *page)
 void remove_from_page_cache(struct page *page)
 {
         struct address_space *mapping = page->mapping;
+        void (*freepage)(struct page *);
 
         BUG_ON(!PageLocked(page));
 
+        freepage = mapping->a_ops->freepage;
         spin_lock_irq(&mapping->tree_lock);
         __remove_from_page_cache(page);
         spin_unlock_irq(&mapping->tree_lock);
         mem_cgroup_uncharge_cache_page(page);
+
+        if (freepage)
+                freepage(page);
 }
 EXPORT_SYMBOL(remove_from_page_cache);
 
diff --git a/mm/truncate.c b/mm/truncate.c
index ba887bff48c5..3c2d5ddfa0d4 100644
--- a/mm/truncate.c
+++ b/mm/truncate.c
@@ -390,6 +390,10 @@ invalidate_complete_page2(struct address_space *mapping, struct page *page)
         __remove_from_page_cache(page);
         spin_unlock_irq(&mapping->tree_lock);
         mem_cgroup_uncharge_cache_page(page);
+
+        if (mapping->a_ops->freepage)
+                mapping->a_ops->freepage(page);
+
         page_cache_release(page);       /* pagecache ref */
         return 1;
 failed:
diff --git a/mm/vmscan.c b/mm/vmscan.c
index d31d7ce52c0e..9ca587c69274 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -494,9 +494,16 @@ static int __remove_mapping(struct address_space *mapping, struct page *page)
                 spin_unlock_irq(&mapping->tree_lock);
                 swapcache_free(swap, page);
         } else {
+                void (*freepage)(struct page *);
+
+                freepage = mapping->a_ops->freepage;
+
                 __remove_from_page_cache(page);
                 spin_unlock_irq(&mapping->tree_lock);
                 mem_cgroup_uncharge_cache_page(page);
+
+                if (freepage != NULL)
+                        freepage(page);
         }
 
         return 1;