diff options
author | Philippe Mathieu-Daudé <philmd@redhat.com> | 2020-09-22 10:38:17 +0200 |
---|---|---|
committer | Stefan Hajnoczi <stefanha@redhat.com> | 2020-10-05 09:35:52 +0100 |
commit | f68453237b9c97f7d1948236a359524c45d7e2d8 (patch) | |
tree | ed1db47dfd9a2c48942ea2eb68b39a2f1dea1b2a /block | |
parent | b02c01a513a17e03e2245feff19b3dcc8c408859 (diff) |
block/nvme: Map doorbells pages write-only
Per the datasheet sections 3.1.13/3.1.14:
"The host should not read the doorbell registers."
As we don't need read access, map the doorbells with write-only
permission. We keep a reference to this mapped address in the
BDRVNVMeState structure.
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20200922083821.578519-3-philmd@redhat.com>
Diffstat (limited to 'block')
-rw-r--r-- | block/nvme.c | 29 |
1 files changed, 19 insertions, 10 deletions
diff --git a/block/nvme.c b/block/nvme.c index 5a4dc6a722..3c834da8fe 100644 --- a/block/nvme.c +++ b/block/nvme.c @@ -31,7 +31,7 @@ #define NVME_SQ_ENTRY_BYTES 64 #define NVME_CQ_ENTRY_BYTES 16 #define NVME_QUEUE_SIZE 128 -#define NVME_BAR_SIZE 8192 +#define NVME_DOORBELL_SIZE 4096 /* * We have to leave one slot empty as that is the full queue case where @@ -84,10 +84,6 @@ typedef struct { /* Memory mapped registers */ typedef volatile struct { NvmeBar ctrl; - struct { - uint32_t sq_tail; - uint32_t cq_head; - } doorbells[]; } NVMeRegs; #define INDEX_ADMIN 0 @@ -103,6 +99,11 @@ struct BDRVNVMeState { AioContext *aio_context; QEMUVFIOState *vfio; NVMeRegs *regs; + /* Memory mapped registers */ + volatile struct { + uint32_t sq_tail; + uint32_t cq_head; + } *doorbells; /* The submission/completion queue pairs. * [0]: admin queue. * [1..]: io queues. @@ -247,14 +248,14 @@ static NVMeQueuePair *nvme_create_queue_pair(BDRVNVMeState *s, error_propagate(errp, local_err); goto fail; } - q->sq.doorbell = &s->regs->doorbells[idx * s->doorbell_scale].sq_tail; + q->sq.doorbell = &s->doorbells[idx * s->doorbell_scale].sq_tail; nvme_init_queue(s, &q->cq, size, NVME_CQ_ENTRY_BYTES, &local_err); if (local_err) { error_propagate(errp, local_err); goto fail; } - q->cq.doorbell = &s->regs->doorbells[idx * s->doorbell_scale].cq_head; + q->cq.doorbell = &s->doorbells[idx * s->doorbell_scale].cq_head; return q; fail: @@ -712,13 +713,12 @@ static int nvme_init(BlockDriverState *bs, const char *device, int namespace, goto out; } - s->regs = qemu_vfio_pci_map_bar(s->vfio, 0, 0, NVME_BAR_SIZE, + s->regs = qemu_vfio_pci_map_bar(s->vfio, 0, 0, sizeof(NvmeBar), PROT_READ | PROT_WRITE, errp); if (!s->regs) { ret = -EINVAL; goto out; } - /* Perform initialize sequence as described in NVMe spec "7.6.1 * Initialization". */ @@ -748,6 +748,13 @@ static int nvme_init(BlockDriverState *bs, const char *device, int namespace, } } + s->doorbells = qemu_vfio_pci_map_bar(s->vfio, 0, sizeof(NvmeBar), + NVME_DOORBELL_SIZE, PROT_WRITE, errp); + if (!s->doorbells) { + ret = -EINVAL; + goto out; + } + /* Set up admin queue. */ s->queues = g_new(NVMeQueuePair *, 1); s->queues[INDEX_ADMIN] = nvme_create_queue_pair(s, aio_context, 0, @@ -873,7 +880,9 @@ static void nvme_close(BlockDriverState *bs) &s->irq_notifier[MSIX_SHARED_IRQ_IDX], false, NULL, NULL); event_notifier_cleanup(&s->irq_notifier[MSIX_SHARED_IRQ_IDX]); - qemu_vfio_pci_unmap_bar(s->vfio, 0, (void *)s->regs, 0, NVME_BAR_SIZE); + qemu_vfio_pci_unmap_bar(s->vfio, 0, (void *)s->doorbells, + sizeof(NvmeBar), NVME_DOORBELL_SIZE); + qemu_vfio_pci_unmap_bar(s->vfio, 0, (void *)s->regs, 0, sizeof(NvmeBar)); qemu_vfio_close(s->vfio); g_free(s->device); |