diff options
-rw-r--r-- | fs/cachefiles/rdwr.c | 78 | ||||
-rw-r--r-- | fs/fscache/page.c | 2 |
2 files changed, 44 insertions, 36 deletions
diff --git a/fs/cachefiles/rdwr.c b/fs/cachefiles/rdwr.c index b4d2438da9a5..00d942540e6c 100644 --- a/fs/cachefiles/rdwr.c +++ b/fs/cachefiles/rdwr.c @@ -914,6 +914,15 @@ int cachefiles_write_page(struct fscache_storage *op, struct page *page) cache = container_of(object->fscache.cache, struct cachefiles_cache, cache); + pos = (loff_t)page->index << PAGE_SHIFT; + + /* We mustn't write more data than we have, so we have to beware of a + * partial page at EOF. + */ + eof = object->fscache.store_limit_l; + if (pos >= eof) + goto error; + /* write the page to the backing filesystem and let it store it in its * own time */ dget(object->backer); @@ -922,47 +931,46 @@ int cachefiles_write_page(struct fscache_storage *op, struct page *page) cache->cache_cred); if (IS_ERR(file)) { ret = PTR_ERR(file); - } else { + goto error_2; + } + if (!file->f_op->write) { ret = -EIO; - if (file->f_op->write) { - pos = (loff_t) page->index << PAGE_SHIFT; - - /* we mustn't write more data than we have, so we have - * to beware of a partial page at EOF */ - eof = object->fscache.store_limit_l; - len = PAGE_SIZE; - if (eof & ~PAGE_MASK) { - ASSERTCMP(pos, <, eof); - if (eof - pos < PAGE_SIZE) { - _debug("cut short %llx to %llx", - pos, eof); - len = eof - pos; - ASSERTCMP(pos + len, ==, eof); - } - } + goto error_2; + } - data = kmap(page); - old_fs = get_fs(); - set_fs(KERNEL_DS); - ret = file->f_op->write( - file, (const void __user *) data, len, &pos); - set_fs(old_fs); - kunmap(page); - if (ret != len) - ret = -EIO; + len = PAGE_SIZE; + if (eof & ~PAGE_MASK) { + if (eof - pos < PAGE_SIZE) { + _debug("cut short %llx to %llx", + pos, eof); + len = eof - pos; + ASSERTCMP(pos + len, ==, eof); } - fput(file); } - if (ret < 0) { - if (ret == -EIO) - cachefiles_io_error_obj( - object, "Write page to backing file failed"); - ret = -ENOBUFS; - } + data = kmap(page); + old_fs = get_fs(); + set_fs(KERNEL_DS); + ret = file->f_op->write( + file, (const void __user *) data, len, &pos); + set_fs(old_fs); + kunmap(page); + fput(file); + if (ret != len) + goto error_eio; + + _leave(" = 0"); + return 0; - _leave(" = %d", ret); - return ret; +error_eio: + ret = -EIO; +error_2: + if (ret == -EIO) + cachefiles_io_error_obj(object, + "Write page to backing file failed"); +error: + _leave(" = -ENOBUFS [%d]", ret); + return -ENOBUFS; } /* diff --git a/fs/fscache/page.c b/fs/fscache/page.c index 3f7a59bfa7ad..c9d52e1a8fa9 100644 --- a/fs/fscache/page.c +++ b/fs/fscache/page.c @@ -676,7 +676,7 @@ static void fscache_write_op(struct fscache_operation *_op) goto superseded; page = results[0]; _debug("gang %d [%lx]", n, page->index); - if (page->index > op->store_limit) { + if (page->index >= op->store_limit) { fscache_stat(&fscache_n_store_pages_over_limit); goto superseded; } |