target: Drop arbitrary maximum I/O size limit
commit 046ba64285a4389ae5e9a7dfa253c6bff3d7c341 upstream.
This patch drops the arbitrary maximum I/O size limit in sbc_parse_cdb(),
which currently for fabric_max_sectors is hardcoded to 8192 (4 MB for 512
byte sector devices), and for hw_max_sectors is a backend driver dependent
value.
This limit is problematic because Linux initiators have only recently
started to honor block limits MAXIMUM TRANSFER LENGTH, and other non-Linux
based initiators (eg: MSFT Fibre Channel) can also generate I/Os larger
than 4 MB in size.
Currently when this happens, the following message will appear on the
target resulting in I/Os being returned with non recoverable status:
SCSI OP 28h with too big sectors 16384 exceeds fabric_max_sectors: 8192
Instead, drop both [fabric,hw]_max_sector checks in sbc_parse_cdb(),
and convert the existing hw_max_sectors into a purely informational
attribute used to represent the granuality that backend driver and/or
subsystem code is splitting I/Os upon.
Also, update FILEIO with an explicit FD_MAX_BYTES check in fd_execute_rw()
to deal with the one special iovec limitiation case.
v2 changes:
- Drop hw_max_sectors check in sbc_parse_cdb()
Reported-by: Lance Gropper <lance.gropper@qosserver.com>
Reported-by: Stefan Priebe <s.priebe@profihost.ag>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Martin K. Petersen <martin.petersen@oracle.com>
Cc: Roland Dreier <roland@purestorage.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/target/target_core_device.c b/drivers/target/target_core_device.c
index 2be407e..4deb0c9 100644
--- a/drivers/target/target_core_device.c
+++ b/drivers/target/target_core_device.c
@@ -1037,10 +1037,10 @@
" changed for TCM/pSCSI\n", dev);
return -EINVAL;
}
- if (optimal_sectors > dev->dev_attrib.fabric_max_sectors) {
+ if (optimal_sectors > dev->dev_attrib.hw_max_sectors) {
pr_err("dev[%p]: Passed optimal_sectors %u cannot be"
- " greater than fabric_max_sectors: %u\n", dev,
- optimal_sectors, dev->dev_attrib.fabric_max_sectors);
+ " greater than hw_max_sectors: %u\n", dev,
+ optimal_sectors, dev->dev_attrib.hw_max_sectors);
return -EINVAL;
}
@@ -1442,7 +1442,6 @@
DA_UNMAP_GRANULARITY_ALIGNMENT_DEFAULT;
dev->dev_attrib.max_write_same_len = DA_MAX_WRITE_SAME_LEN;
dev->dev_attrib.fabric_max_sectors = DA_FABRIC_MAX_SECTORS;
- dev->dev_attrib.optimal_sectors = DA_FABRIC_MAX_SECTORS;
return dev;
}
@@ -1475,6 +1474,7 @@
dev->dev_attrib.hw_max_sectors =
se_dev_align_max_sectors(dev->dev_attrib.hw_max_sectors,
dev->dev_attrib.hw_block_size);
+ dev->dev_attrib.optimal_sectors = dev->dev_attrib.hw_max_sectors;
dev->dev_index = scsi_get_new_index(SCSI_DEVICE_INDEX);
dev->creation_time = get_jiffies_64();
diff --git a/drivers/target/target_core_file.c b/drivers/target/target_core_file.c
index 3b28793..8baaa0a 100644
--- a/drivers/target/target_core_file.c
+++ b/drivers/target/target_core_file.c
@@ -554,7 +554,16 @@
enum dma_data_direction data_direction = cmd->data_direction;
struct se_device *dev = cmd->se_dev;
int ret = 0;
-
+ /*
+ * We are currently limited by the number of iovecs (2048) per
+ * single vfs_[writev,readv] call.
+ */
+ if (cmd->data_length > FD_MAX_BYTES) {
+ pr_err("FILEIO: Not able to process I/O of %u bytes due to"
+ "FD_MAX_BYTES: %u iovec count limitiation\n",
+ cmd->data_length, FD_MAX_BYTES);
+ return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
+ }
/*
* Call vectorized fileio functions to map struct scatterlist
* physical memory addresses to struct iovec virtual memory.
diff --git a/drivers/target/target_core_iblock.c b/drivers/target/target_core_iblock.c
index aa1620a..b358b3d 100644
--- a/drivers/target/target_core_iblock.c
+++ b/drivers/target/target_core_iblock.c
@@ -122,7 +122,7 @@
q = bdev_get_queue(bd);
dev->dev_attrib.hw_block_size = bdev_logical_block_size(bd);
- dev->dev_attrib.hw_max_sectors = UINT_MAX;
+ dev->dev_attrib.hw_max_sectors = queue_max_hw_sectors(q);
dev->dev_attrib.hw_queue_depth = q->nr_requests;
/*
diff --git a/drivers/target/target_core_sbc.c b/drivers/target/target_core_sbc.c
index 0ef75fb..92e6c51 100644
--- a/drivers/target/target_core_sbc.c
+++ b/drivers/target/target_core_sbc.c
@@ -561,21 +561,6 @@
if (cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) {
unsigned long long end_lba;
- if (sectors > dev->dev_attrib.fabric_max_sectors) {
- printk_ratelimited(KERN_ERR "SCSI OP %02xh with too"
- " big sectors %u exceeds fabric_max_sectors:"
- " %u\n", cdb[0], sectors,
- dev->dev_attrib.fabric_max_sectors);
- return TCM_INVALID_CDB_FIELD;
- }
- if (sectors > dev->dev_attrib.hw_max_sectors) {
- printk_ratelimited(KERN_ERR "SCSI OP %02xh with too"
- " big sectors %u exceeds backend hw_max_sectors:"
- " %u\n", cdb[0], sectors,
- dev->dev_attrib.hw_max_sectors);
- return TCM_INVALID_CDB_FIELD;
- }
-
end_lba = dev->transport->get_blocks(dev) + 1;
if (cmd->t_task_lba + sectors > end_lba) {
pr_err("cmd exceeds last lba %llu "
diff --git a/drivers/target/target_core_spc.c b/drivers/target/target_core_spc.c
index 34254b2..9998ae2 100644
--- a/drivers/target/target_core_spc.c
+++ b/drivers/target/target_core_spc.c
@@ -444,7 +444,6 @@
spc_emulate_evpd_b0(struct se_cmd *cmd, unsigned char *buf)
{
struct se_device *dev = cmd->se_dev;
- u32 max_sectors;
int have_tp = 0;
/*
@@ -469,9 +468,7 @@
/*
* Set MAXIMUM TRANSFER LENGTH
*/
- max_sectors = min(dev->dev_attrib.fabric_max_sectors,
- dev->dev_attrib.hw_max_sectors);
- put_unaligned_be32(max_sectors, &buf[8]);
+ put_unaligned_be32(dev->dev_attrib.hw_max_sectors, &buf[8]);
/*
* Set OPTIMAL TRANSFER LENGTH
