Date: Thu, 09 Apr 2026 23:38:09 +0000 From: Warner Losh <imp@FreeBSD.org> To: src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-main@FreeBSD.org Subject: git: 82ff1c334b97 - main - nvme: Allow larger user request sizes Message-ID: <69d83861.30492.23c808d2@gitrepo.freebsd.org>
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The branch main has been updated by imp: URL: https://cgit.FreeBSD.org/src/commit/?id=82ff1c334b97e5b68e6330e90f0aa6ae0f6af9aa commit 82ff1c334b97e5b68e6330e90f0aa6ae0f6af9aa Author: Warner Losh <imp@FreeBSD.org> AuthorDate: 2026-04-09 16:18:31 +0000 Commit: Warner Losh <imp@FreeBSD.org> CommitDate: 2026-04-09 23:37:21 +0000 nvme: Allow larger user request sizes We have a small buffer for pages on the stack, but if the user wants to do an I/O larger than this we currently fail w/o a way for the user to know the max size. It's not hard to allocate an array for the uncommon case of very large I/Os, and the performance advantage of the array is small in that case anyway. In addition, this allows firmware upgrades using the full transfer size of the device as a happy accident too. Sponsored by: Netflix Reviewed by: chs, chuck Differential Revision: https://reviews.freebsd.org/D55638 --- sys/dev/nvme/nvme_ctrlr.c | 48 +++++++++++++++++++++++++++++++++++------------ 1 file changed, 36 insertions(+), 12 deletions(-) diff --git a/sys/dev/nvme/nvme_ctrlr.c b/sys/dev/nvme/nvme_ctrlr.c index b75033300061..e5094e909a24 100644 --- a/sys/dev/nvme/nvme_ctrlr.c +++ b/sys/dev/nvme/nvme_ctrlr.c @@ -1345,30 +1345,52 @@ nvme_ctrlr_shared_handler(void *arg) #define NVME_MAX_PAGES (int)(1024 / sizeof(vm_page_t)) +static int +nvme_page_count(vm_offset_t start, size_t len) +{ + return atop(round_page(start + len) - trunc_page(start)); +} + static int nvme_user_ioctl_req(vm_offset_t addr, size_t len, bool is_read, - vm_page_t *upages, int max_pages, int *npagesp, struct nvme_request **req, + vm_page_t **upages, int max_pages, int *npagesp, struct nvme_request **req, nvme_cb_fn_t cb_fn, void *cb_arg) { vm_prot_t prot = VM_PROT_READ; - int err; + int err, npages; + vm_page_t *upages_us; + + upages_us = *upages; + npages = nvme_page_count(addr, len); + if (npages > atop(maxphys)) + return (EINVAL); + if (npages > NVME_MAX_PAGES) + upages_us = malloc(npages * sizeof(vm_page_t), M_NVME, + M_ZERO | M_WAITOK); if (is_read) prot |= VM_PROT_WRITE; /* Device will write to host memory */ err = vm_fault_hold_pages(&curproc->p_vmspace->vm_map, - addr, len, prot, upages, max_pages, npagesp); - if (err != 0) + addr, len, prot, upages_us, npages, npagesp); + if (err != 0) { + if (*upages != upages_us) + free(upages_us, M_NVME); return (err); + } *req = nvme_allocate_request_null(M_WAITOK, cb_fn, cb_arg); - (*req)->payload = memdesc_vmpages(upages, len, addr & PAGE_MASK); + (*req)->payload = memdesc_vmpages(upages_us, len, addr & PAGE_MASK); (*req)->payload_valid = true; + if (*upages != upages_us) + *upages = upages_us; return (0); } static void -nvme_user_ioctl_free(vm_page_t *pages, int npage) +nvme_user_ioctl_free(vm_page_t *pages, int npage, bool freeit) { vm_page_unhold_pages(pages, npage); + if (freeit) + free(pages, M_NVME); } static void @@ -1400,7 +1422,8 @@ nvme_ctrlr_passthrough_cmd(struct nvme_controller *ctrlr, struct mtx *mtx; int ret = 0; int npages = 0; - vm_page_t upages[NVME_MAX_PAGES]; + vm_page_t upages_small[NVME_MAX_PAGES]; + vm_page_t *upages = upages_small; if (pt->len > 0) { if (pt->len > ctrlr->max_xfer_size) { @@ -1411,7 +1434,7 @@ nvme_ctrlr_passthrough_cmd(struct nvme_controller *ctrlr, } if (is_user) { ret = nvme_user_ioctl_req((vm_offset_t)pt->buf, pt->len, - pt->is_read, upages, nitems(upages), &npages, &req, + pt->is_read, &upages, nitems(upages_small), &npages, &req, nvme_pt_done, pt); if (ret != 0) return (ret); @@ -1449,7 +1472,7 @@ nvme_ctrlr_passthrough_cmd(struct nvme_controller *ctrlr, mtx_unlock(mtx); if (npages > 0) - nvme_user_ioctl_free(upages, npages); + nvme_user_ioctl_free(upages, npages, upages != upages_small); return (ret); } @@ -1477,7 +1500,8 @@ nvme_ctrlr_linux_passthru_cmd(struct nvme_controller *ctrlr, struct mtx *mtx; int ret = 0; int npages = 0; - vm_page_t upages[NVME_MAX_PAGES]; + vm_page_t upages_small[NVME_MAX_PAGES]; + vm_page_t *upages = upages_small; /* * We don't support metadata. @@ -1494,7 +1518,7 @@ nvme_ctrlr_linux_passthru_cmd(struct nvme_controller *ctrlr, } if (is_user) { ret = nvme_user_ioctl_req(npc->addr, npc->data_len, - npc->opcode & 0x1, upages, nitems(upages), &npages, + npc->opcode & 0x1, &upages, nitems(upages), &npages, &req, nvme_npc_done, npc); if (ret != 0) return (ret); @@ -1533,7 +1557,7 @@ nvme_ctrlr_linux_passthru_cmd(struct nvme_controller *ctrlr, mtx_unlock(mtx); if (npages > 0) - nvme_user_ioctl_free(upages, npages); + nvme_user_ioctl_free(upages, npages, upages != upages_small); return (ret); }home | help
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