[PATCH 6/7] nvmet: Remove the data_len field from the nvmet_req struct

From: Logan Gunthorpe
Date: Wed Oct 23 2019 - 12:36:16 EST

Instead of storing the expected length and checking it when it's
executed, just check the length inside the command themselves.

A new helper, nvmet_check_data_len() is created to help with this
check.

Signed-off-by: Christoph Hellwig <hch@xxxxxx>
[logang@xxxxxxxxxxxx: separated out of a larger draft patch from hch]
Signed-off-by: Logan Gunthorpe <logang@xxxxxxxxxxxx>
---
drivers/nvme/target/admin-cmd.c | 35 +++++++++++++++++++++----------
drivers/nvme/target/core.c | 16 ++++++++++----
drivers/nvme/target/discovery.c | 18 ++++++++++------
drivers/nvme/target/fabrics-cmd.c | 15 ++++++++++---
drivers/nvme/target/io-cmd-bdev.c | 19 +++++++++++------
drivers/nvme/target/io-cmd-file.c | 19 ++++++++++-------
drivers/nvme/target/nvmet.h | 3 +--
7 files changed, 86 insertions(+), 39 deletions(-)

diff --git a/drivers/nvme/target/admin-cmd.c b/drivers/nvme/target/admin-cmd.c
index 3665b45d6515..cd2c3a79f3b5 100644
--- a/drivers/nvme/target/admin-cmd.c
+++ b/drivers/nvme/target/admin-cmd.c
@@ -31,7 +31,7 @@ u64 nvmet_get_log_page_offset(struct nvme_command *cmd)

static void nvmet_execute_get_log_page_noop(struct nvmet_req *req)
{
- nvmet_req_complete(req, nvmet_zero_sgl(req, 0, req->data_len));
+ nvmet_req_complete(req, nvmet_zero_sgl(req, 0, req->transfer_len));
}

static void nvmet_execute_get_log_page_error(struct nvmet_req *req)
@@ -134,7 +134,7 @@ static void nvmet_execute_get_log_page_smart(struct nvmet_req *req)
u16 status = NVME_SC_INTERNAL;
unsigned long flags;

- if (req->data_len != sizeof(*log))
+ if (req->transfer_len != sizeof(*log))
goto out;

log = kzalloc(sizeof(*log), GFP_KERNEL);
@@ -196,7 +196,7 @@ static void nvmet_execute_get_log_changed_ns(struct nvmet_req *req)
u16 status = NVME_SC_INTERNAL;
size_t len;

- if (req->data_len != NVME_MAX_CHANGED_NAMESPACES * sizeof(__le32))
+ if (req->transfer_len != NVME_MAX_CHANGED_NAMESPACES * sizeof(__le32))
goto out;

mutex_lock(&ctrl->lock);
@@ -206,7 +206,7 @@ static void nvmet_execute_get_log_changed_ns(struct nvmet_req *req)
len = ctrl->nr_changed_ns * sizeof(__le32);
status = nvmet_copy_to_sgl(req, 0, ctrl->changed_ns_list, len);
if (!status)
- status = nvmet_zero_sgl(req, len, req->data_len - len);
+ status = nvmet_zero_sgl(req, len, req->transfer_len - len);
ctrl->nr_changed_ns = 0;
nvmet_clear_aen_bit(req, NVME_AEN_BIT_NS_ATTR);
mutex_unlock(&ctrl->lock);
@@ -284,6 +284,9 @@ static void nvmet_execute_get_log_page_ana(struct nvmet_req *req)

static void nvmet_execute_get_log_page(struct nvmet_req *req)
{
+ if (!nvmet_check_data_len(req, nvmet_get_log_page_len(req->cmd)))
+ return;
+
switch (req->cmd->get_log_page.lid) {
case NVME_LOG_ERROR:
return nvmet_execute_get_log_page_error(req);
@@ -594,6 +597,9 @@ static void nvmet_execute_identify_desclist(struct nvmet_req *req)

static void nvmet_execute_identify(struct nvmet_req *req)
{
+ if (!nvmet_check_data_len(req, NVME_IDENTIFY_DATA_SIZE))
+ return;
+
switch (req->cmd->identify.cns) {
case NVME_ID_CNS_NS:
return nvmet_execute_identify_ns(req);
@@ -620,6 +626,8 @@ static void nvmet_execute_identify(struct nvmet_req *req)
*/
static void nvmet_execute_abort(struct nvmet_req *req)
{
+ if (!nvmet_check_data_len(req, 0))
+ return;
nvmet_set_result(req, 1);
nvmet_req_complete(req, 0);
}
@@ -704,6 +712,9 @@ static void nvmet_execute_set_features(struct nvmet_req *req)
u32 cdw10 = le32_to_cpu(req->cmd->common.cdw10);
u16 status = 0;

+ if (!nvmet_check_data_len(req, 0))
+ return;
+
switch (cdw10 & 0xff) {
case NVME_FEAT_NUM_QUEUES:
nvmet_set_result(req,
@@ -767,6 +778,9 @@ static void nvmet_execute_get_features(struct nvmet_req *req)
u32 cdw10 = le32_to_cpu(req->cmd->common.cdw10);
u16 status = 0;

+ if (!nvmet_check_data_len(req, 0))
+ return;
+
switch (cdw10 & 0xff) {
/*
* These features are mandatory in the spec, but we don't
@@ -831,6 +845,9 @@ void nvmet_execute_async_event(struct nvmet_req *req)
{
struct nvmet_ctrl *ctrl = req->sq->ctrl;

+ if (!nvmet_check_data_len(req, 0))
+ return;
+
mutex_lock(&ctrl->lock);
if (ctrl->nr_async_event_cmds >= NVMET_ASYNC_EVENTS) {
mutex_unlock(&ctrl->lock);
@@ -847,6 +864,9 @@ void nvmet_execute_keep_alive(struct nvmet_req *req)
{
struct nvmet_ctrl *ctrl = req->sq->ctrl;

+ if (!nvmet_check_data_len(req, 0))
+ return;
+
pr_debug("ctrl %d update keep-alive timer for %d secs\n",
ctrl->cntlid, ctrl->kato);

@@ -866,31 +886,24 @@ u16 nvmet_parse_admin_cmd(struct nvmet_req *req)
switch (cmd->common.opcode) {
case nvme_admin_get_log_page:
req->execute = nvmet_execute_get_log_page;
- req->data_len = nvmet_get_log_page_len(cmd);
return 0;
case nvme_admin_identify:
req->execute = nvmet_execute_identify;
- req->data_len = NVME_IDENTIFY_DATA_SIZE;
return 0;
case nvme_admin_abort_cmd:
req->execute = nvmet_execute_abort;
- req->data_len = 0;
return 0;
case nvme_admin_set_features:
req->execute = nvmet_execute_set_features;
- req->data_len = 0;
return 0;
case nvme_admin_get_features:
req->execute = nvmet_execute_get_features;
- req->data_len = 0;
return 0;
case nvme_admin_async_event:
req->execute = nvmet_execute_async_event;
- req->data_len = 0;
return 0;
case nvme_admin_keep_alive:
req->execute = nvmet_execute_keep_alive;
- req->data_len = 0;
return 0;
}

diff --git a/drivers/nvme/target/core.c b/drivers/nvme/target/core.c
index 3a67e244e568..87fe82ccfa89 100644
--- a/drivers/nvme/target/core.c
+++ b/drivers/nvme/target/core.c
@@ -930,13 +930,21 @@ void nvmet_req_uninit(struct nvmet_req *req)
}
EXPORT_SYMBOL_GPL(nvmet_req_uninit);

-void nvmet_req_execute(struct nvmet_req *req)
+bool nvmet_check_data_len(struct nvmet_req *req, size_t data_len)
{
- if (unlikely(req->data_len != req->transfer_len)) {
+ if (unlikely(data_len != req->transfer_len)) {
req->error_loc = offsetof(struct nvme_common_command, dptr);
nvmet_req_complete(req, NVME_SC_SGL_INVALID_DATA | NVME_SC_DNR);
- } else
- req->execute(req);
+ return false;
+ }
+
+ return true;
+}
+EXPORT_SYMBOL_GPL(nvmet_check_data_len);
+
+void nvmet_req_execute(struct nvmet_req *req)
+{
+ req->execute(req);
}
EXPORT_SYMBOL_GPL(nvmet_req_execute);

diff --git a/drivers/nvme/target/discovery.c b/drivers/nvme/target/discovery.c
index 825e61e61b0c..7a868c3e8e95 100644
--- a/drivers/nvme/target/discovery.c
+++ b/drivers/nvme/target/discovery.c
@@ -171,6 +171,9 @@ static void nvmet_execute_disc_get_log_page(struct nvmet_req *req)
u16 status = 0;
void *buffer;

+ if (!nvmet_check_data_len(req, data_len))
+ return;
+
if (req->cmd->get_log_page.lid != NVME_LOG_DISC) {
req->error_loc =
offsetof(struct nvme_get_log_page_command, lid);
@@ -240,6 +243,9 @@ static void nvmet_execute_disc_identify(struct nvmet_req *req)
struct nvme_id_ctrl *id;
u16 status = 0;

+ if (!nvmet_check_data_len(req, NVME_IDENTIFY_DATA_SIZE))
+ return;
+
if (req->cmd->identify.cns != NVME_ID_CNS_CTRL) {
req->error_loc = offsetof(struct nvme_identify, cns);
status = NVME_SC_INVALID_OPCODE | NVME_SC_DNR;
@@ -286,6 +292,9 @@ static void nvmet_execute_disc_set_features(struct nvmet_req *req)
u32 cdw10 = le32_to_cpu(req->cmd->common.cdw10);
u16 stat;

+ if (!nvmet_check_data_len(req, 0))
+ return;
+
switch (cdw10 & 0xff) {
case NVME_FEAT_KATO:
stat = nvmet_set_feat_kato(req);
@@ -309,6 +318,9 @@ static void nvmet_execute_disc_get_features(struct nvmet_req *req)
u32 cdw10 = le32_to_cpu(req->cmd->common.cdw10);
u16 stat = 0;

+ if (!nvmet_check_data_len(req, 0))
+ return;
+
switch (cdw10 & 0xff) {
case NVME_FEAT_KATO:
nvmet_get_feat_kato(req);
@@ -341,26 +353,20 @@ u16 nvmet_parse_discovery_cmd(struct nvmet_req *req)
switch (cmd->common.opcode) {
case nvme_admin_set_features:
req->execute = nvmet_execute_disc_set_features;
- req->data_len = 0;
return 0;
case nvme_admin_get_features:
req->execute = nvmet_execute_disc_get_features;
- req->data_len = 0;
return 0;
case nvme_admin_async_event:
req->execute = nvmet_execute_async_event;
- req->data_len = 0;
return 0;
case nvme_admin_keep_alive:
req->execute = nvmet_execute_keep_alive;
- req->data_len = 0;
return 0;
case nvme_admin_get_log_page:
- req->data_len = nvmet_get_log_page_len(cmd);
req->execute = nvmet_execute_disc_get_log_page;
return 0;
case nvme_admin_identify:
- req->data_len = NVME_IDENTIFY_DATA_SIZE;
req->execute = nvmet_execute_disc_identify;
return 0;
default:
diff --git a/drivers/nvme/target/fabrics-cmd.c b/drivers/nvme/target/fabrics-cmd.c
index d16b55ffe79f..f7297473d9eb 100644
--- a/drivers/nvme/target/fabrics-cmd.c
+++ b/drivers/nvme/target/fabrics-cmd.c
@@ -12,6 +12,9 @@ static void nvmet_execute_prop_set(struct nvmet_req *req)
u64 val = le64_to_cpu(req->cmd->prop_set.value);
u16 status = 0;

+ if (!nvmet_check_data_len(req, 0))
+ return;
+
if (req->cmd->prop_set.attrib & 1) {
req->error_loc =
offsetof(struct nvmf_property_set_command, attrib);
@@ -38,6 +41,9 @@ static void nvmet_execute_prop_get(struct nvmet_req *req)
u16 status = 0;
u64 val = 0;

+ if (!nvmet_check_data_len(req, 0))
+ return;
+
if (req->cmd->prop_get.attrib & 1) {
switch (le32_to_cpu(req->cmd->prop_get.offset)) {
case NVME_REG_CAP:
@@ -82,11 +88,9 @@ u16 nvmet_parse_fabrics_cmd(struct nvmet_req *req)

switch (cmd->fabrics.fctype) {
case nvme_fabrics_type_property_set:
- req->data_len = 0;
req->execute = nvmet_execute_prop_set;
break;
case nvme_fabrics_type_property_get:
- req->data_len = 0;
req->execute = nvmet_execute_prop_get;
break;
default:
@@ -147,6 +151,9 @@ static void nvmet_execute_admin_connect(struct nvmet_req *req)
struct nvmet_ctrl *ctrl = NULL;
u16 status = 0;

+ if (!nvmet_check_data_len(req, sizeof(struct nvmf_connect_data)))
+ return;
+
d = kmalloc(sizeof(*d), GFP_KERNEL);
if (!d) {
status = NVME_SC_INTERNAL;
@@ -211,6 +218,9 @@ static void nvmet_execute_io_connect(struct nvmet_req *req)
u16 qid = le16_to_cpu(c->qid);
u16 status = 0;

+ if (!nvmet_check_data_len(req, sizeof(struct nvmf_connect_data)))
+ return;
+
d = kmalloc(sizeof(*d), GFP_KERNEL);
if (!d) {
status = NVME_SC_INTERNAL;
@@ -281,7 +291,6 @@ u16 nvmet_parse_connect_cmd(struct nvmet_req *req)
return NVME_SC_INVALID_OPCODE | NVME_SC_DNR;
}

- req->data_len = sizeof(struct nvmf_connect_data);
if (cmd->connect.qid == 0)
req->execute = nvmet_execute_admin_connect;
else
diff --git a/drivers/nvme/target/io-cmd-bdev.c b/drivers/nvme/target/io-cmd-bdev.c
index 32008d85172b..2d62347573fa 100644
--- a/drivers/nvme/target/io-cmd-bdev.c
+++ b/drivers/nvme/target/io-cmd-bdev.c
@@ -150,6 +150,9 @@ static void nvmet_bdev_execute_rw(struct nvmet_req *req)
sector_t sector;
int op, op_flags = 0, i;

+ if (!nvmet_check_data_len(req, nvmet_rw_len(req)))
+ return;
+
if (!req->sg_cnt) {
nvmet_req_complete(req, 0);
return;
@@ -170,7 +173,7 @@ static void nvmet_bdev_execute_rw(struct nvmet_req *req)
sector = le64_to_cpu(req->cmd->rw.slba);
sector <<= (req->ns->blksize_shift - 9);

- if (req->data_len <= NVMET_MAX_INLINE_DATA_LEN) {
+ if (req->transfer_len <= NVMET_MAX_INLINE_DATA_LEN) {
bio = &req->b.inline_bio;
bio_init(bio, req->inline_bvec, ARRAY_SIZE(req->inline_bvec));
} else {
@@ -207,6 +210,9 @@ static void nvmet_bdev_execute_flush(struct nvmet_req *req)
{
struct bio *bio = &req->b.inline_bio;

+ if (!nvmet_check_data_len(req, 0))
+ return;
+
bio_init(bio, req->inline_bvec, ARRAY_SIZE(req->inline_bvec));
bio_set_dev(bio, req->ns->bdev);
bio->bi_private = req;
@@ -274,6 +280,9 @@ static void nvmet_bdev_execute_discard(struct nvmet_req *req)

static void nvmet_bdev_execute_dsm(struct nvmet_req *req)
{
+ if (!nvmet_check_data_len(req, nvmet_dsm_len(req)))
+ return;
+
switch (le32_to_cpu(req->cmd->dsm.attributes)) {
case NVME_DSMGMT_AD:
nvmet_bdev_execute_discard(req);
@@ -295,6 +304,9 @@ static void nvmet_bdev_execute_write_zeroes(struct nvmet_req *req)
sector_t nr_sector;
int ret;

+ if (!nvmet_check_data_len(req, 0))
+ return;
+
sector = le64_to_cpu(write_zeroes->slba) <<
(req->ns->blksize_shift - 9);
nr_sector = (((sector_t)le16_to_cpu(write_zeroes->length) + 1) <<
@@ -319,20 +331,15 @@ u16 nvmet_bdev_parse_io_cmd(struct nvmet_req *req)
case nvme_cmd_read:
case nvme_cmd_write:
req->execute = nvmet_bdev_execute_rw;
- req->data_len = nvmet_rw_len(req);
return 0;
case nvme_cmd_flush:
req->execute = nvmet_bdev_execute_flush;
- req->data_len = 0;
return 0;
case nvme_cmd_dsm:
req->execute = nvmet_bdev_execute_dsm;
- req->data_len = (le32_to_cpu(cmd->dsm.nr) + 1) *
- sizeof(struct nvme_dsm_range);
return 0;
case nvme_cmd_write_zeroes:
req->execute = nvmet_bdev_execute_write_zeroes;
- req->data_len = 0;
return 0;
default:
pr_err("unhandled cmd %d on qid %d\n", cmd->common.opcode,
diff --git a/drivers/nvme/target/io-cmd-file.c b/drivers/nvme/target/io-cmd-file.c
index 7481556da6e6..caebfce06605 100644
--- a/drivers/nvme/target/io-cmd-file.c
+++ b/drivers/nvme/target/io-cmd-file.c
@@ -126,7 +126,7 @@ static void nvmet_file_io_done(struct kiocb *iocb, long ret, long ret2)
mempool_free(req->f.bvec, req->ns->bvec_pool);
}

- if (unlikely(ret != req->data_len))
+ if (unlikely(ret != req->transfer_len))
status = errno_to_nvme_status(req, ret);
nvmet_req_complete(req, status);
}
@@ -146,7 +146,7 @@ static bool nvmet_file_execute_io(struct nvmet_req *req, int ki_flags)
is_sync = true;

pos = le64_to_cpu(req->cmd->rw.slba) << req->ns->blksize_shift;
- if (unlikely(pos + req->data_len > req->ns->size)) {
+ if (unlikely(pos + req->transfer_len > req->ns->size)) {
nvmet_req_complete(req, errno_to_nvme_status(req, -ENOSPC));
return true;
}
@@ -173,7 +173,7 @@ static bool nvmet_file_execute_io(struct nvmet_req *req, int ki_flags)
nr_bvec--;
}

- if (WARN_ON_ONCE(total_len != req->data_len)) {
+ if (WARN_ON_ONCE(total_len != req->transfer_len)) {
ret = -EIO;
goto complete;
}
@@ -232,6 +232,9 @@ static void nvmet_file_execute_rw(struct nvmet_req *req)
{
ssize_t nr_bvec = req->sg_cnt;

+ if (!nvmet_check_data_len(req, nvmet_rw_len(req)))
+ return;
+
if (!req->sg_cnt || !nr_bvec) {
nvmet_req_complete(req, 0);
return;
@@ -273,6 +276,8 @@ static void nvmet_file_flush_work(struct work_struct *w)

static void nvmet_file_execute_flush(struct nvmet_req *req)
{
+ if (!nvmet_check_data_len(req, 0))
+ return;
INIT_WORK(&req->f.work, nvmet_file_flush_work);
schedule_work(&req->f.work);
}
@@ -331,6 +336,8 @@ static void nvmet_file_dsm_work(struct work_struct *w)

static void nvmet_file_execute_dsm(struct nvmet_req *req)
{
+ if (!nvmet_check_data_len(req, nvmet_dsm_len(req)))
+ return;
INIT_WORK(&req->f.work, nvmet_file_dsm_work);
schedule_work(&req->f.work);
}
@@ -359,6 +366,8 @@ static void nvmet_file_write_zeroes_work(struct work_struct *w)

static void nvmet_file_execute_write_zeroes(struct nvmet_req *req)
{
+ if (!nvmet_check_data_len(req, 0))
+ return;
INIT_WORK(&req->f.work, nvmet_file_write_zeroes_work);
schedule_work(&req->f.work);
}
@@ -371,19 +380,15 @@ u16 nvmet_file_parse_io_cmd(struct nvmet_req *req)
case nvme_cmd_read:
case nvme_cmd_write:
req->execute = nvmet_file_execute_rw;
- req->data_len = nvmet_rw_len(req);
return 0;
case nvme_cmd_flush:
req->execute = nvmet_file_execute_flush;
- req->data_len = 0;
return 0;
case nvme_cmd_dsm:
req->execute = nvmet_file_execute_dsm;
- req->data_len = nvmet_dsm_len(req);
return 0;
case nvme_cmd_write_zeroes:
req->execute = nvmet_file_execute_write_zeroes;
- req->data_len = 0;
return 0;
default:
pr_err("unhandled cmd for file ns %d on qid %d\n",
diff --git a/drivers/nvme/target/nvmet.h b/drivers/nvme/target/nvmet.h
index 6ccf2d098d9f..ff55f1005b35 100644
--- a/drivers/nvme/target/nvmet.h
+++ b/drivers/nvme/target/nvmet.h
@@ -304,8 +304,6 @@ struct nvmet_req {
} f;
};
int sg_cnt;
- /* data length as parsed from the command: */
- size_t data_len;
/* data length as parsed from the SGL descriptor: */
size_t transfer_len;

@@ -375,6 +373,7 @@ u16 nvmet_parse_fabrics_cmd(struct nvmet_req *req);
bool nvmet_req_init(struct nvmet_req *req, struct nvmet_cq *cq,
struct nvmet_sq *sq, const struct nvmet_fabrics_ops *ops);
void nvmet_req_uninit(struct nvmet_req *req);
+bool nvmet_check_data_len(struct nvmet_req *req, size_t data_len);
void nvmet_req_execute(struct nvmet_req *req);
void nvmet_req_complete(struct nvmet_req *req, u16 status);
int nvmet_req_alloc_sgl(struct nvmet_req *req);
--
2.20.1