[RFC 6/8] nvmet: Be careful about using iomem accesses when dealing with p2pmem

Logan Gunthorpe
2017-03-30T22:12:37Z

p2pmem will always be iomem so if we ever access it, we should be using
the correct methods to read and write to it.

Signed-off-by: Logan Gunthorpe <logang-OTvnGxWRz7hWk0Htik3J/w@public.gmane.org>
Signed-off-by: Stephen Bates <sbates-pv7U853sEMVWk0Htik3J/w@public.gmane.org>
Signed-off-by: Steve Wise <swise-7bPotxP6k4+P2YhJcF5u+vpXobYPEAuW@public.gmane.org>
---
drivers/nvme/target/core.c | 18 ++++++++++++++++--
drivers/nvme/target/fabrics-cmd.c | 28 +++++++++++++++-------------
drivers/nvme/target/nvmet.h | 1 +
drivers/nvme/target/rdma.c | 13 ++++++-------
4 files changed, 38 insertions(+), 22 deletions(-)

diff --git a/drivers/nvme/target/core.c b/drivers/nvme/target/core.c
index 798653b..a1524d5 100644
--- a/drivers/nvme/target/core.c
+++ b/drivers/nvme/target/core.c
@@ -45,15 +45,29 @@ static struct nvmet_subsys *nvmet_find_get_subsys(struct nvmet_port *port,
u16 nvmet_copy_to_sgl(struct nvmet_req *req, off_t off, const void *buf,
size_t len)
{
- if (sg_pcopy_from_buffer(req->sg, req->sg_cnt, buf, len, off) != len)
+ bool iomem = req->p2pmem;
+ size_t ret;
+
+ ret = sg_copy_buffer(req->sg, req->sg_cnt, (void *)buf, len, off,
+ false, iomem);
+
+ if (ret != len)
return NVME_SC_SGL_INVALID_DATA | NVME_SC_DNR;
+
return 0;
}

u16 nvmet_copy_from_sgl(struct nvmet_req *req, off_t off, void *buf, size_t len)
{
- if (sg_pcopy_to_buffer(req->sg, req->sg_cnt, buf, len, off) != len)
+ bool iomem = req->p2pmem;
+ size_t ret;
+
+ ret = sg_copy_buffer(req->sg, req->sg_cnt, buf, len, off, true,
+ iomem);
+
+ if (ret != len)
return NVME_SC_SGL_INVALID_DATA | NVME_SC_DNR;
+
return 0;
}

diff --git a/drivers/nvme/target/fabrics-cmd.c b/drivers/nvme/target/fabrics-cmd.c
index 8bd022af..9d966f0 100644
--- a/drivers/nvme/target/fabrics-cmd.c
+++ b/drivers/nvme/target/fabrics-cmd.c
@@ -118,11 +118,13 @@ static u16 nvmet_install_queue(struct nvmet_ctrl *ctrl, struct nvmet_req *req)
static void nvmet_execute_admin_connect(struct nvmet_req *req)
{
struct nvmf_connect_command *c = &req->cmd->connect;
- struct nvmf_connect_data *d;
+ struct nvmf_connect_data d;
struct nvmet_ctrl *ctrl = NULL;
u16 status = 0;

- d = kmap(sg_page(req->sg)) + req->sg->offset;
+ status = nvmet_copy_from_sgl(req, 0, &d, sizeof(d));
+ if (status)
+ goto out;

/* zero out initial completion result, assign values as needed */
req->rsp->result.u32 = 0;
@@ -134,16 +136,16 @@ static void nvmet_execute_admin_connect(struct nvmet_req *req)
goto out;
}

- if (unlikely(d->cntlid != cpu_to_le16(0xffff))) {
+ if (unlikely(d.cntlid != cpu_to_le16(0xffff))) {
pr_warn("connect attempt for invalid controller ID %#x\n",
- d->cntlid);
+ d.cntlid);
status = NVME_SC_CONNECT_INVALID_PARAM | NVME_SC_DNR;
req->rsp->result.u32 = IPO_IATTR_CONNECT_DATA(cntlid);
goto out;
}

- status = nvmet_alloc_ctrl(d->subsysnqn, d->hostnqn, req,
- le32_to_cpu(c->kato), &ctrl);
+ status = nvmet_alloc_ctrl(d.subsysnqn, d.hostnqn, req,
+ le32_to_cpu(c->kato), &ctrl);
if (status)
goto out;

@@ -158,19 +160,20 @@ static void nvmet_execute_admin_connect(struct nvmet_req *req)
req->rsp->result.u16 = cpu_to_le16(ctrl->cntlid);

out:
- kunmap(sg_page(req->sg));
nvmet_req_complete(req, status);
}

static void nvmet_execute_io_connect(struct nvmet_req *req)
{
struct nvmf_connect_command *c = &req->cmd->connect;
- struct nvmf_connect_data *d;
+ struct nvmf_connect_data d;
struct nvmet_ctrl *ctrl = NULL;
u16 qid = le16_to_cpu(c->qid);
u16 status = 0;

- d = kmap(sg_page(req->sg)) + req->sg->offset;
+ status = nvmet_copy_from_sgl(req, 0, &d, sizeof(d));
+ if (status)
+ goto out;

/* zero out initial completion result, assign values as needed */
req->rsp->result.u32 = 0;
@@ -182,9 +185,9 @@ static void nvmet_execute_io_connect(struct nvmet_req *req)
goto out;
}

- status = nvmet_ctrl_find_get(d->subsysnqn, d->hostnqn,
- le16_to_cpu(d->cntlid),
- req, &ctrl);
+ status = nvmet_ctrl_find_get(d.subsysnqn, d.hostnqn,
+ le16_to_cpu(d.cntlid),
+ req, &ctrl);
if (status)
goto out;

@@ -205,7 +208,6 @@ static void nvmet_execute_io_connect(struct nvmet_req *req)
pr_info("adding queue %d to ctrl %d.\n", qid, ctrl->cntlid);

out:
- kunmap(sg_page(req->sg));
nvmet_req_complete(req, status);
return;

diff --git a/drivers/nvme/target/nvmet.h b/drivers/nvme/target/nvmet.h
index ab67175..ccd79ed 100644
--- a/drivers/nvme/target/nvmet.h
+++ b/drivers/nvme/target/nvmet.h
@@ -226,6 +226,7 @@ struct nvmet_req {

void (*execute)(struct nvmet_req *req);
struct nvmet_fabrics_ops *ops;
+ struct p2pmem_dev *p2pmem;
};

static inline void nvmet_set_status(struct nvmet_req *req, u16 status)
diff --git a/drivers/nvme/target/rdma.c b/drivers/nvme/target/rdma.c
index 7fd4840..abab544 100644
--- a/drivers/nvme/target/rdma.c
+++ b/drivers/nvme/target/rdma.c
@@ -65,7 +65,6 @@ struct nvmet_rdma_rsp {
struct rdma_rw_ctx rw;

struct nvmet_req req;
- struct p2pmem_dev *p2pmem;

u8 n_rdma;
u32 flags;
@@ -501,7 +500,7 @@ static void nvmet_rdma_release_rsp(struct nvmet_rdma_rsp *rsp)

if (rsp->req.sg != &rsp->cmd->inline_sg)
nvmet_rdma_free_sgl(rsp->req.sg, rsp->req.sg_cnt,
- rsp->p2pmem);
+ rsp->req.p2pmem);

if (unlikely(!list_empty_careful(&queue->rsp_wr_wait_list)))
nvmet_rdma_process_wr_wait_list(queue);
@@ -642,14 +641,14 @@ static u16 nvmet_rdma_map_sgl_keyed(struct nvmet_rdma_rsp *rsp,
if (!len)
return 0;

- rsp->p2pmem = rsp->queue->p2pmem;
+ rsp->req.p2pmem = rsp->queue->p2pmem;
status = nvmet_rdma_alloc_sgl(&rsp->req.sg, &rsp->req.sg_cnt,
- len, rsp->p2pmem);
+ len, rsp->req.p2pmem);

- if (status && rsp->p2pmem) {
- rsp->p2pmem = NULL;
+ if (status && rsp->req.p2pmem) {
+ rsp->req.p2pmem = NULL;
status = nvmet_rdma_alloc_sgl(&rsp->req.sg, &rsp->req.sg_cnt,
- len, rsp->p2pmem);
+ len, rsp->req.p2pmem);
}

if (status)
--
2.1.4