tmpfs: convert to use the new truncate convention
npiggin@suse.de [Wed, 26 May 2010 15:05:36 +0000 (01:05 +1000)]
Cc: Christoph Hellwig <hch@lst.de>
Acked-by: Hugh Dickins <hugh.dickins@tiscali.co.uk>
Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

mm/shmem.c

index 4daf8ce..7e5030a 100644 (file)
@@ -727,10 +727,11 @@ done2:
        if (inode->i_mapping->nrpages && (info->flags & SHMEM_PAGEIN)) {
                /*
                 * Call truncate_inode_pages again: racing shmem_unuse_inode
-                * may have swizzled a page in from swap since vmtruncate or
-                * generic_delete_inode did it, before we lowered next_index.
-                * Also, though shmem_getpage checks i_size before adding to
-                * cache, no recheck after: so fix the narrow window there too.
+                * may have swizzled a page in from swap since
+                * truncate_pagecache or generic_delete_inode did it, before we
+                * lowered next_index.  Also, though shmem_getpage checks
+                * i_size before adding to cache, no recheck after: so fix the
+                * narrow window there too.
                 *
                 * Recalling truncate_inode_pages_range and unmap_mapping_range
                 * every time for punch_hole (which never got a chance to clear
@@ -760,19 +761,16 @@ done2:
        }
 }
 
-static void shmem_truncate(struct inode *inode)
-{
-       shmem_truncate_range(inode, inode->i_size, (loff_t)-1);
-}
-
 static int shmem_notify_change(struct dentry *dentry, struct iattr *attr)
 {
        struct inode *inode = dentry->d_inode;
-       struct page *page = NULL;
        int error;
 
        if (S_ISREG(inode->i_mode) && (attr->ia_valid & ATTR_SIZE)) {
-               if (attr->ia_size < inode->i_size) {
+               loff_t newsize = attr->ia_size;
+               struct page *page = NULL;
+
+               if (newsize < inode->i_size) {
                        /*
                         * If truncating down to a partial page, then
                         * if that page is already allocated, hold it
@@ -780,9 +778,9 @@ static int shmem_notify_change(struct dentry *dentry, struct iattr *attr)
                         * truncate_partial_page cannnot miss it were
                         * it assigned to swap.
                         */
-                       if (attr->ia_size & (PAGE_CACHE_SIZE-1)) {
+                       if (newsize & (PAGE_CACHE_SIZE-1)) {
                                (void) shmem_getpage(inode,
-                                       attr->ia_size>>PAGE_CACHE_SHIFT,
+                                       newsize >> PAGE_CACHE_SHIFT,
                                                &page, SGP_READ, NULL);
                                if (page)
                                        unlock_page(page);
@@ -794,24 +792,29 @@ static int shmem_notify_change(struct dentry *dentry, struct iattr *attr)
                         * if it's being fully truncated to zero-length: the
                         * nrpages check is efficient enough in that case.
                         */
-                       if (attr->ia_size) {
+                       if (newsize) {
                                struct shmem_inode_info *info = SHMEM_I(inode);
                                spin_lock(&info->lock);
                                info->flags &= ~SHMEM_PAGEIN;
                                spin_unlock(&info->lock);
                        }
                }
+
+               error = simple_setsize(inode, newsize);
+               if (page)
+                       page_cache_release(page);
+               if (error)
+                       return error;
+               shmem_truncate_range(inode, newsize, (loff_t)-1);
        }
 
        error = inode_change_ok(inode, attr);
        if (!error)
-               error = inode_setattr(inode, attr);
+               generic_setattr(inode, attr);
 #ifdef CONFIG_TMPFS_POSIX_ACL
        if (!error && (attr->ia_valid & ATTR_MODE))
                error = generic_acl_chmod(inode);
 #endif
-       if (page)
-               page_cache_release(page);
        return error;
 }
 
@@ -819,11 +822,11 @@ static void shmem_delete_inode(struct inode *inode)
 {
        struct shmem_inode_info *info = SHMEM_I(inode);
 
-       if (inode->i_op->truncate == shmem_truncate) {
+       if (inode->i_mapping->a_ops == &shmem_aops) {
                truncate_inode_pages(inode->i_mapping, 0);
                shmem_unacct_size(info->flags, inode->i_size);
                inode->i_size = 0;
-               shmem_truncate(inode);
+               shmem_truncate_range(inode, 0, (loff_t)-1);
                if (!list_empty(&info->swaplist)) {
                        mutex_lock(&shmem_swaplist_mutex);
                        list_del_init(&info->swaplist);
@@ -2022,7 +2025,6 @@ static const struct inode_operations shmem_symlink_inline_operations = {
 };
 
 static const struct inode_operations shmem_symlink_inode_operations = {
-       .truncate       = shmem_truncate,
        .readlink       = generic_readlink,
        .follow_link    = shmem_follow_link,
        .put_link       = shmem_put_link,
@@ -2440,7 +2442,6 @@ static const struct file_operations shmem_file_operations = {
 };
 
 static const struct inode_operations shmem_inode_operations = {
-       .truncate       = shmem_truncate,
        .setattr        = shmem_notify_change,
        .truncate_range = shmem_truncate_range,
 #ifdef CONFIG_TMPFS_POSIX_ACL