| Message ID | 20201022184959.240505-1-its@irrelevant.dk |
|---|---|
| Headers | show |
| Series | hw/block/nvme: dulbe and dsm support | expand |
On Oct 22 23:02, Philippe Mathieu-Daudé wrote: > Hi Klaus, > Hi Philippe, Thanks for your comments! > On 10/22/20 8:49 PM, Klaus Jensen wrote: > > From: Klaus Jensen <k.jensen@samsung.com> > > > > Add support for the Dataset Management command and the Deallocate > > attribute. Deallocation results in discards being sent to the underlying > > block device. Whether of not the blocks are actually deallocated is > > affected by the same factors as Write Zeroes (see previous commit). > > > > format | discard | dsm (512b) dsm (4kb) dsm (64kb) > > Please use B/KiB units which are unambiguous (kb is for kbits) > (if you queue this yourself, you can fix when applying, no need > to repost). > Thanks, I'll change it. > > ------------------------------------------------------ > > qcow2 ignore n n n > > qcow2 unmap n n y > > raw ignore n n n > > raw unmap n y y > > > > Again, a raw format and 4kb LBAs are preferable. > > > > In order to set the Namespace Preferred Deallocate Granularity and > > Alignment fields (NPDG and NPDA), choose a sane minimum discard > > granularity of 4kb. If we are using a passthru device supporting discard > > at a 512b granularity, user should set the discard_granularity property > > Ditto. > > > explicitly. NPDG and NPDA will also account for the cluster_size of the > > block driver if required (i.e. for QCOW2). > > > > See NVM Express 1.3d, Section 6.7 ("Dataset Management command"). > > > > Signed-off-by: Klaus Jensen <k.jensen@samsung.com> > > --- > > hw/block/nvme.h | 2 + > > include/block/nvme.h | 7 ++- > > hw/block/nvme-ns.c | 36 +++++++++++++-- > > hw/block/nvme.c | 101 ++++++++++++++++++++++++++++++++++++++++++- > > 4 files changed, 140 insertions(+), 6 deletions(-) > > > > diff --git a/hw/block/nvme.h b/hw/block/nvme.h > > index e080a2318a50..574333caa3f9 100644 > > --- a/hw/block/nvme.h > > +++ b/hw/block/nvme.h > > @@ -28,6 +28,7 @@ typedef struct NvmeRequest { > > struct NvmeNamespace *ns; > > BlockAIOCB *aiocb; > > uint16_t status; > > + void *opaque; > > NvmeCqe cqe; > > NvmeCmd cmd; > > BlockAcctCookie acct; > > @@ -60,6 +61,7 @@ static inline const char *nvme_io_opc_str(uint8_t opc) > > case NVME_CMD_WRITE: return "NVME_NVM_CMD_WRITE"; > > case NVME_CMD_READ: return "NVME_NVM_CMD_READ"; > > case NVME_CMD_WRITE_ZEROES: return "NVME_NVM_CMD_WRITE_ZEROES"; > > + case NVME_CMD_DSM: return "NVME_NVM_CMD_DSM"; > > default: return "NVME_NVM_CMD_UNKNOWN"; > > } > > } > > diff --git a/include/block/nvme.h b/include/block/nvme.h > > index 966c3bb304bd..e95ff6ca9b37 100644 > > --- a/include/block/nvme.h > > +++ b/include/block/nvme.h > > @@ -990,7 +990,12 @@ typedef struct QEMU_PACKED NvmeIdNs { > > uint16_t nabspf; > > uint16_t noiob; > > uint8_t nvmcap[16]; > > - uint8_t rsvd64[40]; > > + uint16_t npwg; > > + uint16_t npwa; > > + uint16_t npdg; > > + uint16_t npda; > > + uint16_t nows; > > + uint8_t rsvd74[30]; > > uint8_t nguid[16]; > > uint64_t eui64; > > NvmeLBAF lbaf[16]; > > If you consider "block/nvme.h" shared by 2 different subsystems, > it is better to add the changes in a separate patch. That way > the changes can be acked individually. > Sure. Some other stuff here warrents a v6 I think, so I will split it. > > diff --git a/hw/block/nvme-ns.c b/hw/block/nvme-ns.c > > index f1cc734c60f5..840651db7256 100644 > > --- a/hw/block/nvme-ns.c > > +++ b/hw/block/nvme-ns.c > > @@ -28,10 +28,14 @@ > > #include "nvme.h" > > #include "nvme-ns.h" > > -static void nvme_ns_init(NvmeNamespace *ns) > > +#define MIN_DISCARD_GRANULARITY (4 * KiB) > > + > > +static int nvme_ns_init(NvmeNamespace *ns, Error **errp) > > Hmm the Error* argument could be squashed in "hw/block/nvme: > support multiple namespaces". Else better split patch in dumb > units IMHO (maybe a reviewer's taste). > Yeah, I guess I can squash that in. > > { > > + BlockDriverInfo bdi; > > NvmeIdNs *id_ns = &ns->id_ns; > > int lba_index = NVME_ID_NS_FLBAS_INDEX(ns->id_ns.flbas); > > + int npdg, ret; > > ns->id_ns.dlfeat = 0x9; > > @@ -43,8 +47,25 @@ static void nvme_ns_init(NvmeNamespace *ns) > > id_ns->ncap = id_ns->nsze; > > id_ns->nuse = id_ns->ncap; > > - /* support DULBE */ > > - id_ns->nsfeat |= 0x4; > > + /* support DULBE and I/O optimization fields */ > > + id_ns->nsfeat |= (0x4 | 0x10); > > The comment helps, but isn't needed if you use explicit definitions > for these flags. You already introduced the NVME_ID_NS_NSFEAT_DULBE > and NVME_ID_NS_FLBAS_EXTENDED but they are restricted to extract bits. > This is why I personally prefer the registerfields API (see > "hw/registerfields.h"). > I've been wanting to fix those constants - but the convention that they only extract bits pre-dates the nvme device and is from when the nvme block driver was introduced - I have just been following the precedence by defining them like that. > > + > > + npdg = ns->blkconf.discard_granularity / ns->blkconf.logical_block_size; > > + > > + ret = bdrv_get_info(blk_bs(ns->blkconf.blk), &bdi); > > + if (ret < 0) { > > + error_setg_errno(errp, -ret, "could not get block driver info"); > > + return ret; > > + } > > + > > + if (bdi.cluster_size && > > + bdi.cluster_size > ns->blkconf.discard_granularity) { > > + npdg = bdi.cluster_size / ns->blkconf.logical_block_size; > > + } > > + > > + id_ns->npda = id_ns->npdg = npdg - 1; > > + > > + return 0; > > } > > static int nvme_ns_init_blk(NvmeCtrl *n, NvmeNamespace *ns, Error **errp) > > @@ -59,6 +80,11 @@ static int nvme_ns_init_blk(NvmeCtrl *n, NvmeNamespace *ns, Error **errp) > > return -1; > > } > > + if (ns->blkconf.discard_granularity == -1) { > > + ns->blkconf.discard_granularity = > > + MAX(ns->blkconf.logical_block_size, MIN_DISCARD_GRANULARITY); > > + } > > + > > ns->size = blk_getlength(ns->blkconf.blk); > > if (ns->size < 0) { > > error_setg_errno(errp, -ns->size, "could not get blockdev size"); > > @@ -92,7 +118,9 @@ int nvme_ns_setup(NvmeCtrl *n, NvmeNamespace *ns, Error **errp) > > return -1; > > } > > - nvme_ns_init(ns); > > + if (nvme_ns_init(ns, errp)) { > > + return -1; > > + } > > if (nvme_register_namespace(n, ns, errp)) { > > return -1; > > diff --git a/hw/block/nvme.c b/hw/block/nvme.c > > index 4ab0705f5a92..7acb9e9dc38a 100644 > > --- a/hw/block/nvme.c > > +++ b/hw/block/nvme.c > > @@ -959,6 +959,103 @@ static void nvme_rw_cb(void *opaque, int ret) > > nvme_enqueue_req_completion(nvme_cq(req), req); > > } > > +static void nvme_aio_discard_cb(void *opaque, int ret) > > +{ > > + NvmeRequest *req = opaque; > > + int *discards = req->opaque; > > + > > + trace_pci_nvme_aio_discard_cb(nvme_cid(req)); > > + > > + if (ret) { > > + req->status = NVME_INTERNAL_DEV_ERROR; > > + trace_pci_nvme_err_aio(nvme_cid(req), strerror(ret), > > + req->status); > > + } > > + > > + if (discards && --(*discards) > 0) { > > This line is hard to read. > Yes. Probably too clever for my own good. I'll fix it up. > > + return; > > + } > > + > > + g_free(req->opaque); > > + req->opaque = NULL; > > + > > + nvme_enqueue_req_completion(nvme_cq(req), req); > > +} > > + > > +static uint16_t nvme_dsm(NvmeCtrl *n, NvmeRequest *req) > > +{ > > + NvmeNamespace *ns = req->ns; > > + NvmeDsmCmd *dsm = (NvmeDsmCmd *) &req->cmd; > > + NvmeDsmRange *range = NULL; > > g_autofree? > What sorcery is this?! I think I'll just replace it with a stack allocation like Keith suggested. > > + int *discards = NULL; > > + > > + uint32_t attr = le32_to_cpu(dsm->attributes); > > + uint32_t nr = (le32_to_cpu(dsm->nr) & 0xff) + 1; > > + > > + uint16_t status = NVME_SUCCESS; > > + > > + trace_pci_nvme_dsm(nvme_cid(req), nvme_nsid(ns), nr, attr); > > + > > + if (attr & NVME_DSMGMT_AD) { > > + int64_t offset; > > + size_t len; > > + > > + range = g_new(NvmeDsmRange, nr); > > + > > + status = nvme_dma(n, (uint8_t *)range, nr * sizeof(NvmeDsmRange), > > + DMA_DIRECTION_TO_DEVICE, req); > > + if (status) { > > + goto out; > > + } > > + > > + discards = g_new(int, 1); > > + *discards = 1; > > + req->opaque = discards; > > If opaque is a pointer, why not instead using it as an uintptr_t > discards directly without using the heap? > It was a "keep it simple, stupid" thing to just do the allocation. DSM is typically not on the fast path ;) But there is really no reason not to use that here.
On Oct 23 07:25, Klaus Jensen wrote: > On Oct 22 23:02, Philippe Mathieu-Daudé wrote: > > On 10/22/20 8:49 PM, Klaus Jensen wrote: > > > - /* support DULBE */ > > > - id_ns->nsfeat |= 0x4; > > > + /* support DULBE and I/O optimization fields */ > > > + id_ns->nsfeat |= (0x4 | 0x10); > > > > The comment helps, but isn't needed if you use explicit definitions > > for these flags. You already introduced the NVME_ID_NS_NSFEAT_DULBE > > and NVME_ID_NS_FLBAS_EXTENDED but they are restricted to extract bits. > > This is why I personally prefer the registerfields API (see > > "hw/registerfields.h"). > > > > I've been wanting to fix those constants - but the convention that they > only extract bits pre-dates the nvme device and is from when the nvme > block driver was introduced - I have just been following the precedence > by defining them like that. > I did not know about the hw/registerfields.h API. Looks promising!
From: Klaus Jensen <k.jensen@samsung.com> This adds support for the Deallocated or Unwritten Logical Block error recovery feature as well as the Dataset Management command. I wanted to add support for the NPDG and NPDA fields such that the host could get a hint on how many blocks to request deallocation of for the deallocation to actually happen, but I cannot find a realiable way to get the actual block size of the underlying device. If it is an image on a file system we could typically use the host page size, but if it is a raw device, we might have 512 byte sectors that we can issue discards on. And QEMU doesn't seem to provide this without root privileges at least. See the two patches for some gotchas. I also integrated this into my zoned proposal. I'll spare you the v4, nobody cares anyway. But I put it in my repo[1] for posterity. [1]: https://irrelevant.dk/g/pci-nvme.git/tag/?h=zoned-v4. v5: - Restore status code from callback (Keith) v4: - Removed mixed declaration and code (Keith) - Set NPDG and NPDA and account for the blockdev cluster size. Klaus Jensen (2): hw/block/nvme: add dulbe support hw/block/nvme: add the dataset management command hw/block/nvme-ns.h | 4 + hw/block/nvme.h | 2 + include/block/nvme.h | 12 ++- hw/block/nvme-ns.c | 40 +++++++-- hw/block/nvme.c | 184 +++++++++++++++++++++++++++++++++++++++++- hw/block/trace-events | 4 + 6 files changed, 237 insertions(+), 9 deletions(-) -- 2.28.0