Add support for STATX_DIOALIGN to erofs, so that direct I/O alignment restrictions are exposed to userspace in a generic way.
[Before] ``` ./statx_test /mnt/erofs/testfile statx(/mnt/erofs/testfile) = 0 dio mem align:0 dio offset align:0 ``` [After] ``` ./statx_test /mnt/erofs/testfile statx(/mnt/erofs/testfile) = 0 dio mem align:512 dio offset align:512 ``` Signed-off-by: Hongbo Li <lihongb...@huawei.com> --- v2: - Removing the non-bdev case for obtaining the bsize. v1: https://lore.kernel.org/all/afe7b51b-b235-4ad5-80a5-16e0e61e1...@linux.alibaba.com/T/ --- fs/erofs/inode.c | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) diff --git a/fs/erofs/inode.c b/fs/erofs/inode.c index 5f6439a63af7..7c1163e47cb7 100644 --- a/fs/erofs/inode.c +++ b/fs/erofs/inode.c @@ -342,6 +342,23 @@ int erofs_getattr(struct mnt_idmap *idmap, const struct path *path, stat->attributes_mask |= (STATX_ATTR_COMPRESSED | STATX_ATTR_IMMUTABLE); + /* + * Return the DIO alignment restrictions if requested. + * + * In erofs, STATX_DIOALIGN is not supported in ondemand mode and + * the compressed file, so in these cases we report no DIO support. + */ + if ((request_mask & STATX_DIOALIGN) && S_ISREG(inode->i_mode)) { + stat->result_mask |= STATX_DIOALIGN; + if (!erofs_is_fscache_mode(inode->i_sb) && + !erofs_inode_is_data_compressed(EROFS_I(inode)->datalayout)) { + struct block_device *bdev = inode->i_sb->s_bdev; + + stat->dio_mem_align = bdev_logical_block_size(bdev); + stat->dio_offset_align = stat->dio_mem_align; + } + } + generic_fillattr(idmap, request_mask, inode, stat); return 0; } -- 2.34.1
