From f6a341e87c656f1e2e9959cfdd2d02561724558f Mon Sep 17 00:00:00 2001 From: Jiang Yi Date: Fri, 11 Aug 2017 11:29:44 +0800 Subject: [PATCH] target/file: Do not return error for UNMAP if length is zero [ Upstream commit 594e25e73440863981032d76c9b1e33409ceff6e ] The function fd_execute_unmap() in target_core_file.c calles ret = file->f_op->fallocate(file, mode, pos, len); Some filesystems implement fallocate() to return error if length is zero (e.g. btrfs) but according to SCSI Block Commands spec UNMAP should return success for zero length. Signed-off-by: Jiang Yi Signed-off-by: Nicholas Bellinger Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- drivers/target/target_core_file.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/target/target_core_file.c b/drivers/target/target_core_file.c index c629817a8854..9b2c0c773022 100644 --- a/drivers/target/target_core_file.c +++ b/drivers/target/target_core_file.c @@ -482,6 +482,10 @@ fd_execute_unmap(struct se_cmd *cmd, sector_t lba, sector_t nolb) struct inode *inode = file->f_mapping->host; int ret; + if (!nolb) { + return 0; + } + if (cmd->se_dev->dev_attrib.pi_prot_type) { ret = fd_do_prot_unmap(cmd, lba, nolb); if (ret) -- 2.20.1