[dm-devel] [RFC PATCH 3/3] nvme: add the "debug" host driver
Adam Manzanares
a.manzanares at samsung.com
Wed Feb 2 06:01:13 UTC 2022
On Tue, Feb 01, 2022 at 01:33:47PM -0500, Mikulas Patocka wrote:
> This patch adds a new driver "nvme-debug". It uses memory as a backing
> store and it is used to test the copy offload functionality.
>
We have looked at something similar to create a null nvme driver to test
interfaces poking the nvme driver without using the block layer. Have you
considered implementing this in the fabrics code since it is already virtualizng
a ssd controller?
BTW I think having the target code be able to implement simple copy without
moving data over the fabric would be a great way of showing off the command.
> Signed-off-by: Mikulas Patocka <mpatocka at redhat.com>
>
> ---
> drivers/nvme/host/Kconfig | 13
> drivers/nvme/host/Makefile | 1
> drivers/nvme/host/nvme-debug.c | 838 +++++++++++++++++++++++++++++++++++++++++
> 3 files changed, 852 insertions(+)
>
> Index: linux-2.6/drivers/nvme/host/Kconfig
> ===================================================================
> --- linux-2.6.orig/drivers/nvme/host/Kconfig 2022-02-01 18:34:22.000000000 +0100
> +++ linux-2.6/drivers/nvme/host/Kconfig 2022-02-01 18:34:22.000000000 +0100
> @@ -83,3 +83,16 @@ config NVME_TCP
> from https://urldefense.com/v3/__https://protect2.fireeye.com/v1/url?k=26ebb71c-79708e5a-26ea3c53-0cc47a3003e8-a628bd4c53dd84d1&q=1&e=9f16193b-4232-4453-9889-7cdf5d653922&u=https*3A*2F*2Fgithub.com*2Flinux-nvme*2Fnvme-cli__;JSUlJSU!!EwVzqGoTKBqv-0DWAJBm!HyJHAJgOq3M4SIOA0HvhX95q50ACkRtsiHWmAQERqjGLQ0pLb_Jru8QcwOQyix0tTVJA$ .
>
> If unsure, say N.
> +
> +config NVME_DEBUG
> + tristate "NVM Express debug"
> + depends on INET
> + depends on BLOCK
> + select NVME_CORE
> + select NVME_FABRICS
> + select CRYPTO
> + select CRYPTO_CRC32C
> + help
> + This pseudo driver simulates a NVMe adapter.
> +
> + If unsure, say N.
> Index: linux-2.6/drivers/nvme/host/Makefile
> ===================================================================
> --- linux-2.6.orig/drivers/nvme/host/Makefile 2022-02-01 18:34:22.000000000 +0100
> +++ linux-2.6/drivers/nvme/host/Makefile 2022-02-01 18:34:22.000000000 +0100
> @@ -8,6 +8,7 @@ obj-$(CONFIG_NVME_FABRICS) += nvme-fabr
> obj-$(CONFIG_NVME_RDMA) += nvme-rdma.o
> obj-$(CONFIG_NVME_FC) += nvme-fc.o
> obj-$(CONFIG_NVME_TCP) += nvme-tcp.o
> +obj-$(CONFIG_NVME_DEBUG) += nvme-debug.o
>
> nvme-core-y := core.o ioctl.o
> nvme-core-$(CONFIG_TRACING) += trace.o
> Index: linux-2.6/drivers/nvme/host/nvme-debug.c
> ===================================================================
> --- /dev/null 1970-01-01 00:00:00.000000000 +0000
> +++ linux-2.6/drivers/nvme/host/nvme-debug.c 2022-02-01 18:34:22.000000000 +0100
> @@ -0,0 +1,838 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * NVMe debug
> + */
> +
> +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
> +#include <linux/module.h>
> +#include <linux/init.h>
> +#include <linux/slab.h>
> +#include <linux/err.h>
> +#include <linux/blk-mq.h>
> +#include <linux/sort.h>
> +#include <linux/version.h>
> +
> +#include "nvme.h"
> +#include "fabrics.h"
> +
> +static ulong dev_size_mb = 16;
> +module_param_named(dev_size_mb, dev_size_mb, ulong, S_IRUGO | S_IWUSR);
> +MODULE_PARM_DESC(dev_size_mb, "size in MiB of the namespace(def=8)");
> +
> +static unsigned sector_size = 512;
> +module_param_named(sector_size, sector_size, uint, S_IRUGO | S_IWUSR);
> +MODULE_PARM_DESC(sector_size, "logical block size in bytes (def=512)");
> +
> +struct nvme_debug_ctrl {
> + struct nvme_ctrl ctrl;
> + uint32_t reg_cc;
> + struct blk_mq_tag_set admin_tag_set;
> + struct blk_mq_tag_set io_tag_set;
> + struct workqueue_struct *admin_wq;
> + struct workqueue_struct *io_wq;
> + struct list_head namespaces;
> + struct list_head list;
> +};
> +
> +struct nvme_debug_namespace {
> + struct list_head list;
> + uint32_t nsid;
> + unsigned char sector_size_bits;
> + size_t n_sectors;
> + void *space;
> + char uuid[16];
> +};
> +
> +struct nvme_debug_request {
> + struct nvme_request req;
> + struct nvme_command cmd;
> + struct work_struct work;
> +};
> +
> +static LIST_HEAD(nvme_debug_ctrl_list);
> +static DEFINE_MUTEX(nvme_debug_ctrl_mutex);
> +
> +DEFINE_STATIC_PERCPU_RWSEM(nvme_debug_sem);
> +
> +static inline struct nvme_debug_ctrl *to_debug_ctrl(struct nvme_ctrl *nctrl)
> +{
> + return container_of(nctrl, struct nvme_debug_ctrl, ctrl);
> +}
> +
> +static struct nvme_debug_namespace *nvme_debug_find_namespace(struct nvme_debug_ctrl *ctrl, unsigned nsid)
> +{
> + struct nvme_debug_namespace *ns;
> + list_for_each_entry(ns, &ctrl->namespaces, list) {
> + if (ns->nsid == nsid)
> + return ns;
> + }
> + return NULL;
> +}
> +
> +static bool nvme_debug_alloc_namespace(struct nvme_debug_ctrl *ctrl)
> +{
> + struct nvme_debug_namespace *ns;
> + unsigned s;
> + size_t dsm;
> +
> + ns = kmalloc(sizeof(struct nvme_debug_namespace), GFP_KERNEL);
> + if (!ns)
> + goto fail0;
> +
> + ns->nsid = 1;
> + while (nvme_debug_find_namespace(ctrl, ns->nsid))
> + ns->nsid++;
> +
> + s = READ_ONCE(sector_size);
> + if (s < 512 || s > PAGE_SIZE || !is_power_of_2(s))
> + goto fail1;
> + ns->sector_size_bits = __ffs(s);
> + dsm = READ_ONCE(dev_size_mb);
> + ns->n_sectors = dsm << (20 - ns->sector_size_bits);
> + if (ns->n_sectors >> (20 - ns->sector_size_bits) != dsm)
> + goto fail1;
> +
> + if (ns->n_sectors << ns->sector_size_bits >> ns->sector_size_bits != ns->n_sectors)
> + goto fail1;
> +
> + ns->space = vzalloc(ns->n_sectors << ns->sector_size_bits);
> + if (!ns->space)
> + goto fail1;
> +
> + generate_random_uuid(ns->uuid);
> +
> + list_add(&ns->list, &ctrl->namespaces);
> + return true;
> +
> +fail1:
> + kfree(ns);
> +fail0:
> + return false;
> +}
> +
> +static void nvme_debug_free_namespace(struct nvme_debug_namespace *ns)
> +{
> + vfree(ns->space);
> + list_del(&ns->list);
> + kfree(ns);
> +}
> +
> +static int nvme_debug_reg_read32(struct nvme_ctrl *nctrl, u32 off, u32 *val)
> +{
> + struct nvme_debug_ctrl *ctrl = to_debug_ctrl(nctrl);
> + switch (off) {
> + case NVME_REG_VS: {
> + *val = 0x20000;
> + break;
> + }
> + case NVME_REG_CC: {
> + *val = ctrl->reg_cc;
> + break;
> + }
> + case NVME_REG_CSTS: {
> + *val = 0;
> + if (ctrl->reg_cc & NVME_CC_ENABLE)
> + *val |= NVME_CSTS_RDY;
> + if (ctrl->reg_cc & NVME_CC_SHN_MASK)
> + *val |= NVME_CSTS_SHST_CMPLT;
> + break;
> + }
> + default: {
> + printk("nvme_debug_reg_read32: %x\n", off);
> + return -ENOSYS;
> + }
> + }
> + return 0;
> +}
> +
> +int nvme_debug_reg_read64(struct nvme_ctrl *nctrl, u32 off, u64 *val)
> +{
> + switch (off) {
> + case NVME_REG_CAP: {
> + *val = (1ULL << 0) | (1ULL << 37);
> + break;
> + }
> + default: {
> + printk("nvme_debug_reg_read64: %x\n", off);
> + return -ENOSYS;
> + }
> + }
> + return 0;
> +}
> +
> +int nvme_debug_reg_write32(struct nvme_ctrl *nctrl, u32 off, u32 val)
> +{
> + struct nvme_debug_ctrl *ctrl = to_debug_ctrl(nctrl);
> + switch (off) {
> + case NVME_REG_CC: {
> + ctrl->reg_cc = val;
> + break;
> + }
> + default: {
> + printk("nvme_debug_reg_write32: %x, %x\n", off, val);
> + return -ENOSYS;
> + }
> + }
> + return 0;
> +}
> +
> +static void nvme_debug_submit_async_event(struct nvme_ctrl *nctrl)
> +{
> + printk("nvme_debug_submit_async_event\n");
> +}
> +
> +static void nvme_debug_delete_ctrl(struct nvme_ctrl *nctrl)
> +{
> + nvme_shutdown_ctrl(nctrl);
> +}
> +
> +static void nvme_debug_free_namespaces(struct nvme_debug_ctrl *ctrl)
> +{
> + if (!list_empty(&ctrl->namespaces)) {
> + struct nvme_debug_namespace *ns = container_of(ctrl->namespaces.next, struct nvme_debug_namespace, list);
> + nvme_debug_free_namespace(ns);
> + }
> +}
> +
> +static void nvme_debug_free_ctrl(struct nvme_ctrl *nctrl)
> +{
> + struct nvme_debug_ctrl *ctrl = to_debug_ctrl(nctrl);
> +
> + flush_workqueue(ctrl->admin_wq);
> + flush_workqueue(ctrl->io_wq);
> +
> + nvme_debug_free_namespaces(ctrl);
> +
> + if (list_empty(&ctrl->list))
> + goto free_ctrl;
> +
> + mutex_lock(&nvme_debug_ctrl_mutex);
> + list_del(&ctrl->list);
> + mutex_unlock(&nvme_debug_ctrl_mutex);
> +
> + nvmf_free_options(nctrl->opts);
> +free_ctrl:
> + destroy_workqueue(ctrl->admin_wq);
> + destroy_workqueue(ctrl->io_wq);
> + kfree(ctrl);
> +}
> +
> +static int nvme_debug_get_address(struct nvme_ctrl *nctrl, char *buf, int size)
> +{
> + int len = 0;
> + len += snprintf(buf, size, "debug");
> + return len;
> +}
> +
> +static void nvme_debug_reset_ctrl_work(struct work_struct *work)
> +{
> + printk("nvme_reset_ctrl_work\n");
> +}
> +
> +static void copy_data_request(struct request *req, void *data, size_t size, bool to_req)
> +{
> + if (req->rq_flags & RQF_SPECIAL_PAYLOAD) {
> + void *addr;
> + struct bio_vec bv = req->special_vec;
> + addr = kmap_atomic(bv.bv_page);
> + if (to_req) {
> + memcpy(addr + bv.bv_offset, data, bv.bv_len);
> + flush_dcache_page(bv.bv_page);
> + } else {
> + flush_dcache_page(bv.bv_page);
> + memcpy(data, addr + bv.bv_offset, bv.bv_len);
> + }
> + kunmap_atomic(addr);
> + data += bv.bv_len;
> + size -= bv.bv_len;
> + } else {
> + struct req_iterator bi;
> + struct bio_vec bv;
> + rq_for_each_segment(bv, req, bi) {
> + void *addr;
> + addr = kmap_atomic(bv.bv_page);
> + if (to_req) {
> + memcpy(addr + bv.bv_offset, data, bv.bv_len);
> + flush_dcache_page(bv.bv_page);
> + } else {
> + flush_dcache_page(bv.bv_page);
> + memcpy(data, addr + bv.bv_offset, bv.bv_len);
> + }
> + kunmap_atomic(addr);
> + data += bv.bv_len;
> + size -= bv.bv_len;
> + }
> + }
> + if (size)
> + printk("size mismatch: %lx\n", (unsigned long)size);
> +}
> +
> +static void nvme_debug_identify_ns(struct nvme_debug_ctrl *ctrl, struct request *req)
> +{
> + struct nvme_id_ns *id;
> + struct nvme_debug_namespace *ns;
> + struct nvme_debug_request *ndr = blk_mq_rq_to_pdu(req);
> +
> + id = kzalloc(sizeof(struct nvme_id_ns), GFP_NOIO);
> + if (!id) {
> + blk_mq_end_request(req, BLK_STS_RESOURCE);
> + return;
> + }
> +
> + ns = nvme_debug_find_namespace(ctrl, le32_to_cpu(ndr->cmd.identify.nsid));
> + if (!ns) {
> + nvme_req(req)->status = cpu_to_le16(NVME_SC_INVALID_NS);
> + goto free_ret;
> + }
> +
> + id->nsze = cpu_to_le64(ns->n_sectors);
> + id->ncap = id->nsze;
> + id->nuse = id->nsze;
> + /*id->nlbaf = 0;*/
> + id->dlfeat = 0x01;
> + id->lbaf[0].ds = ns->sector_size_bits;
> +
> + copy_data_request(req, id, sizeof(struct nvme_id_ns), true);
> +
> +free_ret:
> + kfree(id);
> + blk_mq_end_request(req, BLK_STS_OK);
> +}
> +
> +static void nvme_debug_identify_ctrl(struct nvme_debug_ctrl *ctrl, struct request *req)
> +{
> + struct nvme_debug_namespace *ns;
> + struct nvme_id_ctrl *id;
> + char ver[9];
> + size_t ver_len;
> +
> + id = kzalloc(sizeof(struct nvme_id_ctrl), GFP_NOIO);
> + if (!id) {
> + blk_mq_end_request(req, BLK_STS_RESOURCE);
> + return;
> + }
> +
> + id->vid = cpu_to_le16(PCI_VENDOR_ID_REDHAT);
> + id->ssvid = cpu_to_le16(PCI_VENDOR_ID_REDHAT);
> + memset(id->sn, ' ', sizeof id->sn);
> + memset(id->mn, ' ', sizeof id->mn);
> + memcpy(id->mn, "nvme-debug", 10);
> + snprintf(ver, sizeof ver, "%X", LINUX_VERSION_CODE);
> + ver_len = min(strlen(ver), sizeof id->fr);
> + memset(id->fr, ' ', sizeof id->fr);
> + memcpy(id->fr, ver, ver_len);
> + memcpy(id->ieee, "\xe9\xf2\x40", sizeof id->ieee);
> + id->ver = cpu_to_le32(0x20000);
> + id->kas = cpu_to_le16(100);
> + id->sqes = 0x66;
> + id->cqes = 0x44;
> + id->maxcmd = cpu_to_le16(1);
> + mutex_lock(&nvme_debug_ctrl_mutex);
> + list_for_each_entry(ns, &ctrl->namespaces, list) {
> + if (ns->nsid > le32_to_cpu(id->nn))
> + id->nn = cpu_to_le32(ns->nsid);
> + }
> + mutex_unlock(&nvme_debug_ctrl_mutex);
> + id->oncs = cpu_to_le16(NVME_CTRL_ONCS_COPY);
> + id->vwc = 0x6;
> + id->mnan = cpu_to_le32(0xffffffff);
> + strcpy(id->subnqn, "nqn.2021-09.com.redhat:nvme-debug");
> + id->ioccsz = cpu_to_le32(4);
> + id->iorcsz = cpu_to_le32(1);
> +
> + copy_data_request(req, id, sizeof(struct nvme_id_ctrl), true);
> +
> + kfree(id);
> + blk_mq_end_request(req, BLK_STS_OK);
> +}
> +
> +static int cmp_ns(const void *a1, const void *a2)
> +{
> + __u32 v1 = le32_to_cpu(*(__u32 *)a1);
> + __u32 v2 = le32_to_cpu(*(__u32 *)a2);
> + if (!v1)
> + v1 = 0xffffffffU;
> + if (!v2)
> + v2 = 0xffffffffU;
> + if (v1 < v2)
> + return -1;
> + if (v1 > v2)
> + return 1;
> + return 0;
> +}
> +
> +static void nvme_debug_identify_active_ns(struct nvme_debug_ctrl *ctrl, struct request *req)
> +{
> + struct nvme_debug_namespace *ns;
> + struct nvme_debug_request *ndr = blk_mq_rq_to_pdu(req);
> + unsigned size;
> + __u32 *id;
> + unsigned idp;
> +
> + if (le32_to_cpu(ndr->cmd.identify.nsid) >= 0xFFFFFFFE) {
> + nvme_req(req)->status = cpu_to_le16(NVME_SC_INVALID_NS);
> + blk_mq_end_request(req, BLK_STS_OK);
> + return;
> + }
> +
> + mutex_lock(&nvme_debug_ctrl_mutex);
> + size = 0;
> + list_for_each_entry(ns, &ctrl->namespaces, list) {
> + size++;
> + }
> + size = min(size, 1024U);
> +
> + id = kzalloc(sizeof(__u32) * size, GFP_NOIO);
> + if (!id) {
> + mutex_unlock(&nvme_debug_ctrl_mutex);
> + blk_mq_end_request(req, BLK_STS_RESOURCE);
> + return;
> + }
> +
> + idp = 0;
> + list_for_each_entry(ns, &ctrl->namespaces, list) {
> + if (ns->nsid > le32_to_cpu(ndr->cmd.identify.nsid))
> + id[idp++] = cpu_to_le32(ns->nsid);
> + }
> + mutex_unlock(&nvme_debug_ctrl_mutex);
> + sort(id, idp, sizeof(__u32), cmp_ns, NULL);
> +
> + copy_data_request(req, id, sizeof(__u32) * 1024, true);
> +
> + kfree(id);
> + blk_mq_end_request(req, BLK_STS_OK);
> +}
> +
> +static void nvme_debug_identify_ns_desc_list(struct nvme_debug_ctrl *ctrl, struct request *req)
> +{
> + struct nvme_ns_id_desc *id;
> + struct nvme_debug_namespace *ns;
> + struct nvme_debug_request *ndr = blk_mq_rq_to_pdu(req);
> + id = kzalloc(4096, GFP_NOIO);
> + if (!id) {
> + blk_mq_end_request(req, BLK_STS_RESOURCE);
> + return;
> + }
> +
> + ns = nvme_debug_find_namespace(ctrl, le32_to_cpu(ndr->cmd.identify.nsid));
> + if (!ns) {
> + nvme_req(req)->status = cpu_to_le16(NVME_SC_INVALID_NS);
> + goto free_ret;
> + }
> +
> + id->nidt = NVME_NIDT_UUID;
> + id->nidl = NVME_NIDT_UUID_LEN;
> + memcpy((char *)(id + 1), ns->uuid, NVME_NIDT_UUID_LEN);
> +
> + copy_data_request(req, id, 4096, true);
> +
> +free_ret:
> + kfree(id);
> + blk_mq_end_request(req, BLK_STS_OK);
> +}
> +
> +static void nvme_debug_identify_ctrl_cs(struct request *req)
> +{
> + struct nvme_id_ctrl_nvm *id;
> + id = kzalloc(sizeof(struct nvme_id_ctrl_nvm), GFP_NOIO);
> + if (!id) {
> + blk_mq_end_request(req, BLK_STS_RESOURCE);
> + return;
> + }
> +
> + copy_data_request(req, id, sizeof(struct nvme_id_ctrl_nvm), true);
> +
> + kfree(id);
> + blk_mq_end_request(req, BLK_STS_OK);
> +}
> +
> +static void nvme_debug_admin_rq(struct work_struct *w)
> +{
> + struct nvme_debug_request *ndr = container_of(w, struct nvme_debug_request, work);
> + struct request *req = (struct request *)ndr - 1;
> + struct nvme_debug_ctrl *ctrl = to_debug_ctrl(ndr->req.ctrl);
> +
> + switch (ndr->cmd.common.opcode) {
> + case nvme_admin_identify: {
> + switch (ndr->cmd.identify.cns) {
> + case NVME_ID_CNS_NS: {
> + percpu_down_read(&nvme_debug_sem);
> + nvme_debug_identify_ns(ctrl, req);
> + percpu_up_read(&nvme_debug_sem);
> + return;
> + };
> + case NVME_ID_CNS_CTRL: {
> + percpu_down_read(&nvme_debug_sem);
> + nvme_debug_identify_ctrl(ctrl, req);
> + percpu_up_read(&nvme_debug_sem);
> + return;
> + }
> + case NVME_ID_CNS_NS_ACTIVE_LIST: {
> + percpu_down_read(&nvme_debug_sem);
> + nvme_debug_identify_active_ns(ctrl, req);
> + percpu_up_read(&nvme_debug_sem);
> + return;
> + }
> + case NVME_ID_CNS_NS_DESC_LIST: {
> + percpu_down_read(&nvme_debug_sem);
> + nvme_debug_identify_ns_desc_list(ctrl, req);
> + percpu_up_read(&nvme_debug_sem);
> + return;
> + }
> + case NVME_ID_CNS_CS_CTRL: {
> + percpu_down_read(&nvme_debug_sem);
> + nvme_debug_identify_ctrl_cs(req);
> + percpu_up_read(&nvme_debug_sem);
> + return;
> + }
> + default: {
> + printk("nvme_admin_identify: %x\n", ndr->cmd.identify.cns);
> + break;
> + }
> + }
> + break;
> + }
> + default: {
> + printk("nvme_debug_admin_rq: %x\n", ndr->cmd.common.opcode);
> + break;
> + }
> + }
> + blk_mq_end_request(req, BLK_STS_NOTSUPP);
> +}
> +
> +static void nvme_debug_rw(struct nvme_debug_namespace *ns, struct request *req)
> +{
> + struct nvme_debug_request *ndr = blk_mq_rq_to_pdu(req);
> + __u64 lba = cpu_to_le64(ndr->cmd.rw.slba);
> + __u64 len = (__u64)cpu_to_le16(ndr->cmd.rw.length) + 1;
> + void *addr;
> + if (unlikely(lba + len < lba) || unlikely(lba + len > ns->n_sectors)) {
> + blk_mq_end_request(req, BLK_STS_NOTSUPP);
> + return;
> + }
> + addr = ns->space + (lba << ns->sector_size_bits);
> + copy_data_request(req, addr, len << ns->sector_size_bits, ndr->cmd.rw.opcode == nvme_cmd_read);
> + blk_mq_end_request(req, BLK_STS_OK);
> +}
> +
> +static void nvme_debug_copy(struct nvme_debug_namespace *ns, struct request *req)
> +{
> + struct nvme_debug_request *ndr = blk_mq_rq_to_pdu(req);
> + __u64 dlba = cpu_to_le64(ndr->cmd.copy.sdlba);
> + unsigned n_descs = ndr->cmd.copy.length + 1;
> + struct nvme_copy_desc *descs;
> + unsigned i, ret;
> +
> + descs = kmalloc(sizeof(struct nvme_copy_desc) * n_descs, GFP_NOIO | __GFP_NORETRY | __GFP_NOWARN);
> + if (!descs) {
> + blk_mq_end_request(req, BLK_STS_RESOURCE);
> + return;
> + }
> +
> + copy_data_request(req, descs, sizeof(struct nvme_copy_desc) * n_descs, false);
> +
> + for (i = 0; i < n_descs; i++) {
> + struct nvme_copy_desc *desc = &descs[i];
> + __u64 slba = cpu_to_le64(desc->slba);
> + __u64 len = (__u64)cpu_to_le16(desc->length) + 1;
> + void *saddr, *daddr;
> +
> + if (unlikely(slba + len < slba) || unlikely(slba + len > ns->n_sectors) ||
> + unlikely(dlba + len < dlba) || unlikely(dlba + len > ns->n_sectors)) {
> + ret = BLK_STS_NOTSUPP;
> + goto free_ret;
> + }
> +
> + saddr = ns->space + (slba << ns->sector_size_bits);
> + daddr = ns->space + (dlba << ns->sector_size_bits);
> +
> + memcpy(daddr, saddr, len << ns->sector_size_bits);
> +
> + dlba += len;
> + }
> +
> + ret = BLK_STS_OK;
> +
> +free_ret:
> + kfree(descs);
> +
> + blk_mq_end_request(req, ret);
> +}
> +
> +static void nvme_debug_io_rq(struct work_struct *w)
> +{
> + struct nvme_debug_request *ndr = container_of(w, struct nvme_debug_request, work);
> + struct request *req = (struct request *)ndr - 1;
> + struct nvme_debug_ctrl *ctrl = to_debug_ctrl(ndr->req.ctrl);
> + __u32 nsid = le32_to_cpu(ndr->cmd.common.nsid);
> + struct nvme_debug_namespace *ns;
> +
> + percpu_down_read(&nvme_debug_sem);
> + ns = nvme_debug_find_namespace(ctrl, nsid);
> + if (unlikely(!ns))
> + goto ret_notsupp;
> +
> + switch (ndr->cmd.common.opcode) {
> + case nvme_cmd_flush: {
> + blk_mq_end_request(req, BLK_STS_OK);
> + goto ret;
> + }
> + case nvme_cmd_read:
> + case nvme_cmd_write: {
> + nvme_debug_rw(ns, req);
> + goto ret;
> + }
> + case nvme_cmd_copy: {
> + nvme_debug_copy(ns, req);
> + goto ret;
> + }
> + default: {
> + printk("nvme_debug_io_rq: %x\n", ndr->cmd.common.opcode);
> + break;
> + }
> + }
> +ret_notsupp:
> + blk_mq_end_request(req, BLK_STS_NOTSUPP);
> +ret:
> + percpu_up_read(&nvme_debug_sem);
> +}
> +
> +static blk_status_t nvme_debug_queue_rq(struct blk_mq_hw_ctx *hctx, const struct blk_mq_queue_data *bd)
> +{
> + struct request *req = bd->rq;
> + struct nvme_debug_request *ndr = blk_mq_rq_to_pdu(req);
> + struct nvme_debug_ctrl *ctrl = to_debug_ctrl(ndr->req.ctrl);
> + struct nvme_ns *ns = hctx->queue->queuedata;
> + blk_status_t r;
> +
> + r = nvme_setup_cmd(ns, req);
> + if (unlikely(r))
> + return r;
> +
> + if (!ns) {
> + INIT_WORK(&ndr->work, nvme_debug_admin_rq);
> + queue_work(ctrl->admin_wq, &ndr->work);
> + return BLK_STS_OK;
> + } else if (unlikely((req->cmd_flags & REQ_OP_MASK) == REQ_OP_COPY_READ_TOKEN)) {
> + blk_mq_end_request(req, BLK_STS_OK);
> + return BLK_STS_OK;
> + } else {
> + INIT_WORK(&ndr->work, nvme_debug_io_rq);
> + queue_work(ctrl->io_wq, &ndr->work);
> + return BLK_STS_OK;
> + }
> +}
> +
> +static int nvme_debug_init_request(struct blk_mq_tag_set *set, struct request *req, unsigned hctx_idx, unsigned numa_node)
> +{
> + struct nvme_debug_ctrl *ctrl = set->driver_data;
> + struct nvme_debug_request *ndr = blk_mq_rq_to_pdu(req);
> + nvme_req(req)->ctrl = &ctrl->ctrl;
> + nvme_req(req)->cmd = &ndr->cmd;
> + return 0;
> +}
> +
> +static int nvme_debug_init_hctx(struct blk_mq_hw_ctx *hctx, void *data, unsigned hctx_idx)
> +{
> + struct nvme_debug_ctrl *ctrl = data;
> + hctx->driver_data = ctrl;
> + return 0;
> +}
> +
> +static const struct blk_mq_ops nvme_debug_mq_ops = {
> + .queue_rq = nvme_debug_queue_rq,
> + .init_request = nvme_debug_init_request,
> + .init_hctx = nvme_debug_init_hctx,
> +};
> +
> +static int nvme_debug_configure_admin_queue(struct nvme_debug_ctrl *ctrl)
> +{
> + int r;
> +
> + memset(&ctrl->admin_tag_set, 0, sizeof(ctrl->admin_tag_set));
> + ctrl->admin_tag_set.ops = &nvme_debug_mq_ops;
> + ctrl->admin_tag_set.queue_depth = NVME_AQ_MQ_TAG_DEPTH;
> + ctrl->admin_tag_set.reserved_tags = NVMF_RESERVED_TAGS;
> + ctrl->admin_tag_set.numa_node = ctrl->ctrl.numa_node;
> + ctrl->admin_tag_set.cmd_size = sizeof(struct nvme_debug_request);
> + ctrl->admin_tag_set.driver_data = ctrl;
> + ctrl->admin_tag_set.nr_hw_queues = 1;
> + ctrl->admin_tag_set.timeout = NVME_ADMIN_TIMEOUT;
> + ctrl->admin_tag_set.flags = BLK_MQ_F_NO_SCHED;
> +
> + r = blk_mq_alloc_tag_set(&ctrl->admin_tag_set);
> + if (r)
> + goto ret0;
> + ctrl->ctrl.admin_tagset = &ctrl->admin_tag_set;
> +
> + ctrl->ctrl.admin_q = blk_mq_init_queue(&ctrl->admin_tag_set);
> + if (IS_ERR(ctrl->ctrl.admin_q)) {
> + r = PTR_ERR(ctrl->ctrl.admin_q);
> + goto ret1;
> + }
> +
> + r = nvme_enable_ctrl(&ctrl->ctrl);
> + if (r)
> + goto ret2;
> +
> + nvme_start_admin_queue(&ctrl->ctrl);
> +
> + r = nvme_init_ctrl_finish(&ctrl->ctrl);
> + if (r)
> + goto ret3;
> +
> + return 0;
> +
> +ret3:
> + nvme_stop_admin_queue(&ctrl->ctrl);
> + blk_sync_queue(ctrl->ctrl.admin_q);
> +ret2:
> + blk_cleanup_queue(ctrl->ctrl.admin_q);
> +ret1:
> + blk_mq_free_tag_set(&ctrl->admin_tag_set);
> +ret0:
> + return r;
> +}
> +
> +static int nvme_debug_configure_io_queue(struct nvme_debug_ctrl *ctrl)
> +{
> + int r;
> +
> + memset(&ctrl->io_tag_set, 0, sizeof(ctrl->io_tag_set));
> + ctrl->io_tag_set.ops = &nvme_debug_mq_ops;
> + ctrl->io_tag_set.queue_depth = NVME_AQ_MQ_TAG_DEPTH;
> + ctrl->io_tag_set.reserved_tags = NVMF_RESERVED_TAGS;
> + ctrl->io_tag_set.numa_node = ctrl->ctrl.numa_node;
> + ctrl->io_tag_set.cmd_size = sizeof(struct nvme_debug_request);
> + ctrl->io_tag_set.driver_data = ctrl;
> + ctrl->io_tag_set.nr_hw_queues = 1;
> + ctrl->io_tag_set.timeout = NVME_ADMIN_TIMEOUT;
> + ctrl->io_tag_set.flags = BLK_MQ_F_NO_SCHED;
> +
> + r = blk_mq_alloc_tag_set(&ctrl->io_tag_set);
> + if (r)
> + goto ret0;
> + ctrl->ctrl.tagset = &ctrl->io_tag_set;
> + return 0;
> +
> +ret0:
> + return r;
> +}
> +
> +static const struct nvme_ctrl_ops nvme_debug_ctrl_ops = {
> + .name = "debug",
> + .module = THIS_MODULE,
> + .flags = NVME_F_FABRICS,
> + .reg_read32 = nvme_debug_reg_read32,
> + .reg_read64 = nvme_debug_reg_read64,
> + .reg_write32 = nvme_debug_reg_write32,
> + .free_ctrl = nvme_debug_free_ctrl,
> + .submit_async_event = nvme_debug_submit_async_event,
> + .delete_ctrl = nvme_debug_delete_ctrl,
> + .get_address = nvme_debug_get_address,
> +};
> +
> +static struct nvme_ctrl *nvme_debug_create_ctrl(struct device *dev,
> + struct nvmf_ctrl_options *opts)
> +{
> + int r;
> + struct nvme_debug_ctrl *ctrl;
> +
> + ctrl = kzalloc(sizeof(struct nvme_debug_ctrl), GFP_KERNEL);
> + if (!ctrl) {
> + r = -ENOMEM;
> + goto ret0;
> + }
> +
> + INIT_LIST_HEAD(&ctrl->list);
> + INIT_LIST_HEAD(&ctrl->namespaces);
> + ctrl->ctrl.opts = opts;
> + ctrl->ctrl.queue_count = 2;
> + INIT_WORK(&ctrl->ctrl.reset_work, nvme_debug_reset_ctrl_work);
> +
> + ctrl->admin_wq = alloc_workqueue("nvme-debug-admin", WQ_MEM_RECLAIM | WQ_UNBOUND, 1);
> + if (!ctrl->admin_wq)
> + goto ret1;
> +
> + ctrl->io_wq = alloc_workqueue("nvme-debug-io", WQ_MEM_RECLAIM, 0);
> + if (!ctrl->io_wq)
> + goto ret1;
> +
> + if (!nvme_debug_alloc_namespace(ctrl)) {
> + r = -ENOMEM;
> + goto ret1;
> + }
> +
> + r = nvme_init_ctrl(&ctrl->ctrl, dev, &nvme_debug_ctrl_ops, 0);
> + if (r)
> + goto ret1;
> +
> + if (!nvme_change_ctrl_state(&ctrl->ctrl, NVME_CTRL_CONNECTING))
> + goto ret2;
> +
> + r = nvme_debug_configure_admin_queue(ctrl);
> + if (r)
> + goto ret2;
> +
> + r = nvme_debug_configure_io_queue(ctrl);
> + if (r)
> + goto ret2;
> +
> + if (!nvme_change_ctrl_state(&ctrl->ctrl, NVME_CTRL_LIVE))
> + goto ret2;
> +
> + nvme_start_ctrl(&ctrl->ctrl);
> +
> + mutex_lock(&nvme_debug_ctrl_mutex);
> + list_add_tail(&ctrl->list, &nvme_debug_ctrl_list);
> + mutex_unlock(&nvme_debug_ctrl_mutex);
> +
> + return &ctrl->ctrl;
> +
> +ret2:
> + nvme_uninit_ctrl(&ctrl->ctrl);
> + nvme_put_ctrl(&ctrl->ctrl);
> + return ERR_PTR(r);
> +ret1:
> + nvme_debug_free_namespaces(ctrl);
> + if (ctrl->admin_wq)
> + destroy_workqueue(ctrl->admin_wq);
> + if (ctrl->io_wq)
> + destroy_workqueue(ctrl->io_wq);
> + kfree(ctrl);
> +ret0:
> + return ERR_PTR(r);
> +}
> +
> +static struct nvmf_transport_ops nvme_debug_transport = {
> + .name = "debug",
> + .module = THIS_MODULE,
> + .required_opts = NVMF_OPT_TRADDR,
> + .allowed_opts = NVMF_OPT_CTRL_LOSS_TMO,
> + .create_ctrl = nvme_debug_create_ctrl,
> +};
> +
> +static int __init nvme_debug_init_module(void)
> +{
> + nvmf_register_transport(&nvme_debug_transport);
> + return 0;
> +}
> +
> +static void __exit nvme_debug_cleanup_module(void)
> +{
> + struct nvme_debug_ctrl *ctrl;
> +
> + nvmf_unregister_transport(&nvme_debug_transport);
> +
> + mutex_lock(&nvme_debug_ctrl_mutex);
> + list_for_each_entry(ctrl, &nvme_debug_ctrl_list, list) {
> + nvme_delete_ctrl(&ctrl->ctrl);
> + }
> + mutex_unlock(&nvme_debug_ctrl_mutex);
> + flush_workqueue(nvme_delete_wq);
> +}
> +
> +module_init(nvme_debug_init_module);
> +module_exit(nvme_debug_cleanup_module);
> +
> +MODULE_LICENSE("GPL v2");
>
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