diff options
Diffstat (limited to 'mm/shmem.c')
-rw-r--r-- | mm/shmem.c | 111 |
1 files changed, 87 insertions, 24 deletions
diff --git a/mm/shmem.c b/mm/shmem.c index 0cd7f66f1c66..7e5030ae18ff 100644 --- a/mm/shmem.c +++ b/mm/shmem.c @@ -433,8 +433,6 @@ static swp_entry_t *shmem_swp_alloc(struct shmem_inode_info *info, unsigned long spin_unlock(&info->lock); page = shmem_dir_alloc(mapping_gfp_mask(inode->i_mapping)); - if (page) - set_page_private(page, 0); spin_lock(&info->lock); if (!page) { @@ -729,10 +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 @@ -762,19 +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 @@ -782,9 +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); @@ -796,24 +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; } @@ -821,11 +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); @@ -2024,7 +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, @@ -2435,14 +2435,13 @@ static const struct file_operations shmem_file_operations = { .write = do_sync_write, .aio_read = shmem_file_aio_read, .aio_write = generic_file_aio_write, - .fsync = simple_sync_file, + .fsync = noop_fsync, .splice_read = generic_file_splice_read, .splice_write = generic_file_splice_write, #endif }; 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 @@ -2561,6 +2560,45 @@ out4: return error; } +#ifdef CONFIG_CGROUP_MEM_RES_CTLR +/** + * mem_cgroup_get_shmem_target - find a page or entry assigned to the shmem file + * @inode: the inode to be searched + * @pgoff: the offset to be searched + * @pagep: the pointer for the found page to be stored + * @ent: the pointer for the found swap entry to be stored + * + * If a page is found, refcount of it is incremented. Callers should handle + * these refcount. + */ +void mem_cgroup_get_shmem_target(struct inode *inode, pgoff_t pgoff, + struct page **pagep, swp_entry_t *ent) +{ + swp_entry_t entry = { .val = 0 }, *ptr; + struct page *page = NULL; + struct shmem_inode_info *info = SHMEM_I(inode); + + if ((pgoff << PAGE_CACHE_SHIFT) >= i_size_read(inode)) + goto out; + + spin_lock(&info->lock); + ptr = shmem_swp_entry(info, pgoff, NULL); +#ifdef CONFIG_SWAP + if (ptr && ptr->val) { + entry.val = ptr->val; + page = find_get_page(&swapper_space, entry.val); + } else +#endif + page = find_get_page(inode->i_mapping, pgoff); + if (ptr) + shmem_swp_unmap(ptr); + spin_unlock(&info->lock); +out: + *pagep = page; + *ent = entry; +} +#endif + #else /* !CONFIG_SHMEM */ /* @@ -2600,6 +2638,31 @@ int shmem_lock(struct file *file, int lock, struct user_struct *user) return 0; } +#ifdef CONFIG_CGROUP_MEM_RES_CTLR +/** + * mem_cgroup_get_shmem_target - find a page or entry assigned to the shmem file + * @inode: the inode to be searched + * @pgoff: the offset to be searched + * @pagep: the pointer for the found page to be stored + * @ent: the pointer for the found swap entry to be stored + * + * If a page is found, refcount of it is incremented. Callers should handle + * these refcount. + */ +void mem_cgroup_get_shmem_target(struct inode *inode, pgoff_t pgoff, + struct page **pagep, swp_entry_t *ent) +{ + struct page *page = NULL; + + if ((pgoff << PAGE_CACHE_SHIFT) >= i_size_read(inode)) + goto out; + page = find_get_page(inode->i_mapping, pgoff); +out: + *pagep = page; + *ent = (swp_entry_t){ .val = 0 }; +} +#endif + #define shmem_vm_ops generic_file_vm_ops #define shmem_file_operations ramfs_file_operations #define shmem_get_inode(sb, dir, mode, dev, flags) ramfs_get_inode(sb, dir, mode, dev) |