On Mon, 2020-03-16 at 07:28 -0700, Klaus Jensen wrote:
> From: Klaus Jensen <k.jen...@samsung.com>
>
> The num_queues device paramater has a slightly confusing meaning because
> it accounts for the admin queue pair which is not really optional.
> Secondly, it is really a maximum value of queues allowed.
>
> Add a new max_ioqpairs parameter that only accounts for I/O queue pairs,
> but keep num_queues for compatibility.
>
> Signed-off-by: Klaus Jensen <k.jen...@samsung.com>
> ---
> hw/block/nvme.c | 45 ++++++++++++++++++++++++++-------------------
> hw/block/nvme.h | 4 +++-
> 2 files changed, 29 insertions(+), 20 deletions(-)
>
> diff --git a/hw/block/nvme.c b/hw/block/nvme.c
> index 7cf7cf55143e..7dfd8a1a392d 100644
> --- a/hw/block/nvme.c
> +++ b/hw/block/nvme.c
> @@ -19,7 +19,7 @@
> * -drive file=<file>,if=none,id=<drive_id>
> * -device nvme,drive=<drive_id>,serial=<serial>,id=<id[optional]>, \
> * cmb_size_mb=<cmb_size_mb[optional]>, \
> - * num_queues=<N[optional]>
> + * max_ioqpairs=<N[optional]>
> *
> * Note cmb_size_mb denotes size of CMB in MB. CMB is assumed to be at
> * offset 0 in BAR2 and supports only WDS, RDS and SQS for now.
> @@ -27,6 +27,7 @@
>
> #include "qemu/osdep.h"
> #include "qemu/units.h"
> +#include "qemu/error-report.h"
> #include "hw/block/block.h"
> #include "hw/pci/msix.h"
> #include "hw/pci/pci.h"
> @@ -72,12 +73,12 @@ static void nvme_addr_read(NvmeCtrl *n, hwaddr addr, void
> *buf, int size)
>
> static int nvme_check_sqid(NvmeCtrl *n, uint16_t sqid)
> {
> - return sqid < n->params.num_queues && n->sq[sqid] != NULL ? 0 : -1;
> + return sqid < n->params.max_ioqpairs + 1 && n->sq[sqid] != NULL ? 0 : -1;
> }
>
> static int nvme_check_cqid(NvmeCtrl *n, uint16_t cqid)
> {
> - return cqid < n->params.num_queues && n->cq[cqid] != NULL ? 0 : -1;
> + return cqid < n->params.max_ioqpairs + 1 && n->cq[cqid] != NULL ? 0 : -1;
> }
>
> static void nvme_inc_cq_tail(NvmeCQueue *cq)
> @@ -639,7 +640,7 @@ static uint16_t nvme_create_cq(NvmeCtrl *n, NvmeCmd *cmd)
> trace_nvme_dev_err_invalid_create_cq_addr(prp1);
> return NVME_INVALID_FIELD | NVME_DNR;
> }
> - if (unlikely(vector > n->params.num_queues)) {
> + if (unlikely(vector > n->params.max_ioqpairs + 1)) {
> trace_nvme_dev_err_invalid_create_cq_vector(vector);
> return NVME_INVALID_IRQ_VECTOR | NVME_DNR;
> }
> @@ -803,8 +804,8 @@ static uint16_t nvme_get_feature(NvmeCtrl *n, NvmeCmd
> *cmd, NvmeRequest *req)
> trace_nvme_dev_getfeat_vwcache(result ? "enabled" : "disabled");
> break;
> case NVME_NUMBER_OF_QUEUES:
> - result = cpu_to_le32((n->params.num_queues - 2) |
> - ((n->params.num_queues - 2) << 16));
> + result = cpu_to_le32((n->params.max_ioqpairs - 1) |
> + ((n->params.max_ioqpairs - 1) << 16));
> trace_nvme_dev_getfeat_numq(result);
> break;
> case NVME_TIMESTAMP:
> @@ -848,10 +849,10 @@ static uint16_t nvme_set_feature(NvmeCtrl *n, NvmeCmd
> *cmd, NvmeRequest *req)
> case NVME_NUMBER_OF_QUEUES:
> trace_nvme_dev_setfeat_numq((dw11 & 0xFFFF) + 1,
> ((dw11 >> 16) & 0xFFFF) + 1,
> - n->params.num_queues - 1,
> - n->params.num_queues - 1);
> - req->cqe.result = cpu_to_le32((n->params.num_queues - 2) |
> - ((n->params.num_queues - 2) << 16));
> + n->params.max_ioqpairs,
> + n->params.max_ioqpairs);
> + req->cqe.result = cpu_to_le32((n->params.max_ioqpairs - 1) |
> + ((n->params.max_ioqpairs - 1) << 16));
> break;
> case NVME_TIMESTAMP:
> return nvme_set_feature_timestamp(n, cmd);
> @@ -924,12 +925,12 @@ static void nvme_clear_ctrl(NvmeCtrl *n)
>
> blk_drain(n->conf.blk);
>
> - for (i = 0; i < n->params.num_queues; i++) {
> + for (i = 0; i < n->params.max_ioqpairs + 1; i++) {
> if (n->sq[i] != NULL) {
> nvme_free_sq(n->sq[i], n);
> }
> }
> - for (i = 0; i < n->params.num_queues; i++) {
> + for (i = 0; i < n->params.max_ioqpairs + 1; i++) {
> if (n->cq[i] != NULL) {
> nvme_free_cq(n->cq[i], n);
> }
> @@ -1332,9 +1333,15 @@ static void nvme_realize(PCIDevice *pci_dev, Error
> **errp)
> int64_t bs_size;
> uint8_t *pci_conf;
>
> - if (!n->params.num_queues) {
> - error_setg(errp, "num_queues can't be zero");
> - return;
> + if (n->params.num_queues) {
> + warn_report("nvme: num_queues is deprecated; please use max_ioqpairs
> "
> + "instead");
> +
> + n->params.max_ioqpairs = n->params.num_queues - 1;
> + }
> +
> + if (!n->params.max_ioqpairs) {
> + error_setg(errp, "max_ioqpairs can't be less than 1");
> }
This is not even a nitpick, but just and idea.
It might be worth it to allow max_ioqpairs=0 to simulate a 'broken'
nvme controller. I know that kernel has special handling for such controllers,
which include only creation of the control character device (/dev/nvme*) through
which the user can submit commands to try and 'fix' the controller (by
re-uploading firmware
maybe or something like that).
>
> if (!n->conf.blk) {
> @@ -1365,19 +1372,19 @@ static void nvme_realize(PCIDevice *pci_dev, Error
> **errp)
> pcie_endpoint_cap_init(pci_dev, 0x80);
>
> n->num_namespaces = 1;
> - n->reg_size = pow2ceil(0x1004 + 2 * (n->params.num_queues + 1) * 4);
> + n->reg_size = pow2ceil(0x1008 + 2 * (n->params.max_ioqpairs) * 4);
I hate to say it, but it looks like this thing (which I mentioned to you in V5)
was pre-existing bug, which is indeed fixed now.
In theory such fixes should go to separate patches, but in this case, I guess
it would
be too much to ask for it.
Maybe mention this in the commit message instead, so that this fix doesn't stay
hidden like that?
> n->ns_size = bs_size / (uint64_t)n->num_namespaces;
>
> n->namespaces = g_new0(NvmeNamespace, n->num_namespaces);
> - n->sq = g_new0(NvmeSQueue *, n->params.num_queues);
> - n->cq = g_new0(NvmeCQueue *, n->params.num_queues);
> + n->sq = g_new0(NvmeSQueue *, n->params.max_ioqpairs + 1);
> + n->cq = g_new0(NvmeCQueue *, n->params.max_ioqpairs + 1);
>
> memory_region_init_io(&n->iomem, OBJECT(n), &nvme_mmio_ops, n,
> "nvme", n->reg_size);
> pci_register_bar(pci_dev, 0,
> PCI_BASE_ADDRESS_SPACE_MEMORY | PCI_BASE_ADDRESS_MEM_TYPE_64,
> &n->iomem);
> - msix_init_exclusive_bar(pci_dev, n->params.num_queues, 4, NULL);
> + msix_init_exclusive_bar(pci_dev, n->params.max_ioqpairs + 1, 4, NULL);
>
> id->vid = cpu_to_le16(pci_get_word(pci_conf + PCI_VENDOR_ID));
> id->ssvid = cpu_to_le16(pci_get_word(pci_conf +
> PCI_SUBSYSTEM_VENDOR_ID));
> diff --git a/hw/block/nvme.h b/hw/block/nvme.h
> index 9957c4a200e2..98f5b9479244 100644
> --- a/hw/block/nvme.h
> +++ b/hw/block/nvme.h
> @@ -6,11 +6,13 @@
> #define DEFINE_NVME_PROPERTIES(_state, _props) \
> DEFINE_PROP_STRING("serial", _state, _props.serial), \
> DEFINE_PROP_UINT32("cmb_size_mb", _state, _props.cmb_size_mb, 0), \
> - DEFINE_PROP_UINT32("num_queues", _state, _props.num_queues, 64)
> + DEFINE_PROP_UINT32("num_queues", _state, _props.num_queues, 0), \
> + DEFINE_PROP_UINT32("max_ioqpairs", _state, _props.max_ioqpairs, 64)
>
> typedef struct NvmeParams {
> char *serial;
> uint32_t num_queues;
> + uint32_t max_ioqpairs;
> uint32_t cmb_size_mb;
> } NvmeParams;
>
Reviewed-by: Maxim Levitsky <mlevi...@redhat.com>
Best regards,
Maxim Levitsky
