From 1c05cf9058027dd80630d54aa3527eb2e3152e80 Mon Sep 17 00:00:00 2001 From: Logan Gunthorpe Date: Tue, 18 Apr 2017 17:32:15 -0600 Subject: [PATCH] nvmet: convert from kmap to nvmet_copy_from_sgl This is safer as it doesn't rely on the data being stored in a single page in an sgl. It also aids our effort to start phasing out users of sg_page. See [1]. For this we kmalloc some memory, copy to it and free at the end. Note: we can't allocate this memory on the stack as the kbuild test robot reports some frame size overflows on i386. [1] https://lwn.net/Articles/720053/ Signed-off-by: Logan Gunthorpe Reviewed-by: Christoph Hellwig Reviewed-by: Max Gurtovoy Signed-off-by: Sagi Grimberg --- drivers/nvme/target/fabrics-cmd.c | 32 ++++++++++++++++++++++++------- 1 file changed, 25 insertions(+), 7 deletions(-) diff --git a/drivers/nvme/target/fabrics-cmd.c b/drivers/nvme/target/fabrics-cmd.c index 2a3c15b57f6e..3cc17269504b 100644 --- a/drivers/nvme/target/fabrics-cmd.c +++ b/drivers/nvme/target/fabrics-cmd.c @@ -122,7 +122,15 @@ static void nvmet_execute_admin_connect(struct nvmet_req *req) struct nvmet_ctrl *ctrl = NULL; u16 status = 0; - d = kmap(sg_page(req->sg)) + req->sg->offset; + d = kmalloc(sizeof(*d), GFP_KERNEL); + if (!d) { + status = NVME_SC_INTERNAL; + goto complete; + } + + 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; @@ -143,7 +151,7 @@ static void nvmet_execute_admin_connect(struct nvmet_req *req) } status = nvmet_alloc_ctrl(d->subsysnqn, d->hostnqn, req, - le32_to_cpu(c->kato), &ctrl); + le32_to_cpu(c->kato), &ctrl); if (status) goto out; @@ -158,7 +166,8 @@ 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)); + kfree(d); +complete: nvmet_req_complete(req, status); } @@ -170,7 +179,15 @@ static void nvmet_execute_io_connect(struct nvmet_req *req) u16 qid = le16_to_cpu(c->qid); u16 status = 0; - d = kmap(sg_page(req->sg)) + req->sg->offset; + d = kmalloc(sizeof(*d), GFP_KERNEL); + if (!d) { + status = NVME_SC_INTERNAL; + goto complete; + } + + 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; @@ -183,8 +200,8 @@ static void nvmet_execute_io_connect(struct nvmet_req *req) } status = nvmet_ctrl_find_get(d->subsysnqn, d->hostnqn, - le16_to_cpu(d->cntlid), - req, &ctrl); + le16_to_cpu(d->cntlid), + req, &ctrl); if (status) goto out; @@ -205,7 +222,8 @@ 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)); + kfree(d); +complete: nvmet_req_complete(req, status); return; -- 2.20.1