diff options
Diffstat (limited to 'kernel/fs/cachefiles/rdwr.c')
-rw-r--r-- | kernel/fs/cachefiles/rdwr.c | 75 |
1 files changed, 38 insertions, 37 deletions
diff --git a/kernel/fs/cachefiles/rdwr.c b/kernel/fs/cachefiles/rdwr.c index 3cbb0e834..c0f3da392 100644 --- a/kernel/fs/cachefiles/rdwr.c +++ b/kernel/fs/cachefiles/rdwr.c @@ -414,9 +414,6 @@ int cachefiles_read_or_alloc_page(struct fscache_retrieval *op, ASSERT(inode->i_mapping->a_ops->readpages); /* calculate the shift required to use bmap */ - if (inode->i_sb->s_blocksize > PAGE_SIZE) - goto enobufs; - shift = PAGE_SHIFT - inode->i_sb->s_blocksize_bits; op->op.flags &= FSCACHE_OP_KEEP_FLAGS; @@ -711,9 +708,6 @@ int cachefiles_read_or_alloc_pages(struct fscache_retrieval *op, ASSERT(inode->i_mapping->a_ops->readpages); /* calculate the shift required to use bmap */ - if (inode->i_sb->s_blocksize > PAGE_SIZE) - goto all_enobufs; - shift = PAGE_SHIFT - inode->i_sb->s_blocksize_bits; pagevec_init(&pagevec, 0); @@ -885,7 +879,7 @@ int cachefiles_write_page(struct fscache_storage *op, struct page *page) loff_t pos, eof; size_t len; void *data; - int ret; + int ret = -ENOBUFS; ASSERT(op != NULL); ASSERT(page != NULL); @@ -905,6 +899,15 @@ 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 */ path.mnt = cache->mnt; @@ -912,40 +915,38 @@ int cachefiles_write_page(struct fscache_storage *op, struct page *page) file = dentry_open(&path, O_RDWR | O_LARGEFILE, cache->cache_cred); if (IS_ERR(file)) { ret = PTR_ERR(file); - } else { - 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); - } - } - - data = kmap(page); - ret = __kernel_write(file, data, len, &pos); - kunmap(page); - if (ret != len) - ret = -EIO; - fput(file); + goto error_2; } - if (ret < 0) { - if (ret == -EIO) - cachefiles_io_error_obj( - object, "Write page to backing file failed"); - ret = -ENOBUFS; + 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); + } } - _leave(" = %d", ret); - return ret; + data = kmap(page); + ret = __kernel_write(file, data, len, &pos); + kunmap(page); + fput(file); + if (ret != len) + goto error_eio; + + _leave(" = 0"); + return 0; + +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; } /* |