Re: [PATCH v5 10/26] nvme: add support for the get log page command

From: Maxim Levitsky <mlevitsk@redhat.com>
To: Klaus Birkelund Jensen <its@irrelevant.dk>
Cc: Kevin Wolf <kwolf@redhat.com>,
	Beata Michalska <beata.michalska@linaro.org>,
	qemu-block@nongnu.org, Klaus Jensen <k.jensen@samsung.com>,
	qemu-devel@nongnu.org, Max Reitz <mreitz@redhat.com>,
	Keith Busch <kbusch@kernel.org>,
	Javier Gonzalez <javier.gonz@samsung.com>
Subject: Re: [PATCH v5 10/26] nvme: add support for the get log page command
Date: Wed, 25 Mar 2020 12:24:53 +0200	[thread overview]
Message-ID: <de6e9c304f9ec856f3c5c701aee0b588a044bc38.camel@redhat.com> (raw)
In-Reply-To: <20200316074517.wvbz2psaienlx3iq@apples.localdomain>

On Mon, 2020-03-16 at 00:45 -0700, Klaus Birkelund Jensen wrote:
> On Feb 12 11:35, Maxim Levitsky wrote:
> > On Tue, 2020-02-04 at 10:51 +0100, Klaus Jensen wrote:
> > > Add support for the Get Log Page command and basic implementations of
> > > the mandatory Error Information, SMART / Health Information and Firmware
> > > Slot Information log pages.
> > > 
> > > In violation of the specification, the SMART / Health Information log
> > > page does not persist information over the lifetime of the controller
> > > because the device has no place to store such persistent state.
> > 
> > Yea, not the end of the world.
> > > 
> > > Note that the LPA field in the Identify Controller data structure
> > > intentionally has bit 0 cleared because there is no namespace specific
> > > information in the SMART / Health information log page.
> > 
> > Makes sense.
> > > 
> > > Required for compliance with NVMe revision 1.2.1. See NVM Express 1.2.1,
> > > Section 5.10 ("Get Log Page command").
> > > 
> > > Signed-off-by: Klaus Jensen <klaus.jensen@cnexlabs.com>
> > > ---
> > >  hw/block/nvme.c       | 122 +++++++++++++++++++++++++++++++++++++++++-
> > >  hw/block/nvme.h       |  10 ++++
> > >  hw/block/trace-events |   2 +
> > >  include/block/nvme.h  |   2 +-
> > >  4 files changed, 134 insertions(+), 2 deletions(-)
> > > 
> > > diff --git a/hw/block/nvme.c b/hw/block/nvme.c
> > > index f72348344832..468c36918042 100644
> > > --- a/hw/block/nvme.c
> > > +++ b/hw/block/nvme.c
> > > @@ -569,6 +569,123 @@ static uint16_t nvme_create_sq(NvmeCtrl *n, NvmeCmd *cmd)
> > >      return NVME_SUCCESS;
> > >  }
> > >  
> > > +static uint16_t nvme_smart_info(NvmeCtrl *n, NvmeCmd *cmd, uint32_t buf_len,
> > > +    uint64_t off, NvmeRequest *req)
> > > +{
> > > +    uint64_t prp1 = le64_to_cpu(cmd->prp1);
> > > +    uint64_t prp2 = le64_to_cpu(cmd->prp2);
> > > +    uint32_t nsid = le32_to_cpu(cmd->nsid);
> > > +
> > > +    uint32_t trans_len;
> > > +    time_t current_ms;
> > > +    uint64_t units_read = 0, units_written = 0, read_commands = 0,
> > > +        write_commands = 0;
> > > +    NvmeSmartLog smart;
> > > +    BlockAcctStats *s;
> > > +
> > > +    if (nsid && nsid != 0xffffffff) {
> > > +        return NVME_INVALID_FIELD | NVME_DNR;
> > > +    }
> > > +
> > > +    s = blk_get_stats(n->conf.blk);
> > > +
> > > +    units_read = s->nr_bytes[BLOCK_ACCT_READ] >> BDRV_SECTOR_BITS;
> > > +    units_written = s->nr_bytes[BLOCK_ACCT_WRITE] >> BDRV_SECTOR_BITS;
> > > +    read_commands = s->nr_ops[BLOCK_ACCT_READ];
> > > +    write_commands = s->nr_ops[BLOCK_ACCT_WRITE];
> > > +
> > > +    if (off > sizeof(smart)) {
> > > +        return NVME_INVALID_FIELD | NVME_DNR;
> > > +    }
> > > +
> > > +    trans_len = MIN(sizeof(smart) - off, buf_len);
> > > +
> > > +    memset(&smart, 0x0, sizeof(smart));
> > > +
> > > +    smart.data_units_read[0] = cpu_to_le64(units_read / 1000);
> > > +    smart.data_units_written[0] = cpu_to_le64(units_written / 1000);
> > > +    smart.host_read_commands[0] = cpu_to_le64(read_commands);
> > > +    smart.host_write_commands[0] = cpu_to_le64(write_commands);
> > > +
> > > +    smart.temperature[0] = n->temperature & 0xff;
> > > +    smart.temperature[1] = (n->temperature >> 8) & 0xff;
> > > +
> > > +    if ((n->temperature > n->features.temp_thresh_hi) ||
> > > +        (n->temperature < n->features.temp_thresh_low)) {
> > > +        smart.critical_warning |= NVME_SMART_TEMPERATURE;
> > > +    }
> > > +
> > > +    current_ms = qemu_clock_get_ms(QEMU_CLOCK_VIRTUAL);
> > > +    smart.power_on_hours[0] = cpu_to_le64(
> > > +        (((current_ms - n->starttime_ms) / 1000) / 60) / 60);
> > > +
> > > +    return nvme_dma_read_prp(n, (uint8_t *) &smart + off, trans_len, prp1,
> > > +        prp2);
> > > +}
> > 
> > Looks OK.
> > > +
> > > +static uint16_t nvme_fw_log_info(NvmeCtrl *n, NvmeCmd *cmd, uint32_t buf_len,
> > > +    uint64_t off, NvmeRequest *req)
> > > +{
> > > +    uint32_t trans_len;
> > > +    uint64_t prp1 = le64_to_cpu(cmd->prp1);
> > > +    uint64_t prp2 = le64_to_cpu(cmd->prp2);
> > > +    NvmeFwSlotInfoLog fw_log;
> > > +
> > > +    if (off > sizeof(fw_log)) {
> > > +        return NVME_INVALID_FIELD | NVME_DNR;
> > > +    }
> > > +
> > > +    memset(&fw_log, 0, sizeof(NvmeFwSlotInfoLog));
> > > +
> > > +    trans_len = MIN(sizeof(fw_log) - off, buf_len);
> > > +
> > > +    return nvme_dma_read_prp(n, (uint8_t *) &fw_log + off, trans_len, prp1,
> > > +        prp2);
> > > +}
> > 
> > Looks OK
> > > +
> > > +static uint16_t nvme_get_log(NvmeCtrl *n, NvmeCmd *cmd, NvmeRequest *req)
> > > +{
> > > +    uint32_t dw10 = le32_to_cpu(cmd->cdw10);
> > > +    uint32_t dw11 = le32_to_cpu(cmd->cdw11);
> > > +    uint32_t dw12 = le32_to_cpu(cmd->cdw12);
> > > +    uint32_t dw13 = le32_to_cpu(cmd->cdw13);
> > > +    uint8_t  lid = dw10 & 0xff;
> > > +    uint8_t  rae = (dw10 >> 15) & 0x1;
> > > +    uint32_t numdl, numdu;
> > > +    uint64_t off, lpol, lpou;
> > > +    size_t   len;
> > > +
> > > +    numdl = (dw10 >> 16);
> > > +    numdu = (dw11 & 0xffff);
> > > +    lpol = dw12;
> > > +    lpou = dw13;
> > > +
> > > +    len = (((numdu << 16) | numdl) + 1) << 2;
> > > +    off = (lpou << 32ULL) | lpol;
> > > +
> > > +    if (off & 0x3) {
> > > +        return NVME_INVALID_FIELD | NVME_DNR;
> > > +    }
> > 
> > Good. 
> > Note that there are plenty of other places in the driver that don't honor
> > such tiny formal bits of the spec, like for instance checking for the reserved
> > bits in commands.
> 
> Yeah. I know. You think its fair we leave that for subsequent patches?
> It's not like its breaking the device, but compliance is not complete.
I don't have a strong opinion on this one, I would just bump the spec version in the last patch.

> 
> > > +
> > > +    trace_nvme_dev_get_log(nvme_cid(req), lid, rae, len, off);
> > > +
> > > +    switch (lid) {
> > > +    case NVME_LOG_ERROR_INFO:
> > > +        if (off) {
> > > +            return NVME_INVALID_FIELD | NVME_DNR;
> > > +        }
> > 
> > I think you might want to memset the user given buffer to zero:
> > 
> > "This is a 64-bit incrementing error count, indicating a unique identifier for this error.
> > The error count starts at 1h, is incremented for each unique error log entry, and is retained across
> > power off conditions. A value of 0h indicates an invalid entry; this value is used when there are
> > lost entries or when there are fewer errors than the maximum number of entries the controller
> > supports."
> 
> Good catch. Fixed!
> 
> > > +
> > > +        return NVME_SUCCESS;
> > > +    case NVME_LOG_SMART_INFO:
> > > +        return nvme_smart_info(n, cmd, len, off, req);
> > > +    case NVME_LOG_FW_SLOT_INFO:
> > > +        return nvme_fw_log_info(n, cmd, len, off, req);
> > > +    default:
> > > +        trace_nvme_dev_err_invalid_log_page(nvme_cid(req), lid);
> > > +        return NVME_INVALID_FIELD | NVME_DNR;
> > > +    }
> > > +}
> > 
> > 
> > > +
> > >  static void nvme_free_cq(NvmeCQueue *cq, NvmeCtrl *n)
> > >  {
> > >      n->cq[cq->cqid] = NULL;
> > > @@ -914,6 +1031,8 @@ static uint16_t nvme_admin_cmd(NvmeCtrl *n, NvmeCmd *cmd, NvmeRequest *req)
> > >          return nvme_del_sq(n, cmd);
> > >      case NVME_ADM_CMD_CREATE_SQ:
> > >          return nvme_create_sq(n, cmd);
> > > +    case NVME_ADM_CMD_GET_LOG_PAGE:
> > > +        return nvme_get_log(n, cmd, req);
> > >      case NVME_ADM_CMD_DELETE_CQ:
> > >          return nvme_del_cq(n, cmd);
> > >      case NVME_ADM_CMD_CREATE_CQ:
> > > @@ -1411,6 +1530,7 @@ static void nvme_init_state(NvmeCtrl *n)
> > >  
> > >      n->temperature = NVME_TEMPERATURE;
> > >      n->features.temp_thresh_hi = NVME_TEMPERATURE_WARNING;
> > > +    n->starttime_ms = qemu_clock_get_ms(QEMU_CLOCK_VIRTUAL);
> > >  }
> > >  
> > >  static void nvme_init_cmb(NvmeCtrl *n, PCIDevice *pci_dev)
> > > @@ -1491,7 +1611,7 @@ static void nvme_init_ctrl(NvmeCtrl *n)
> > >       */
> > >      id->acl = 3;
> > >      id->frmw = 7 << 1;
> > > -    id->lpa = 1 << 0;
> > > +    id->lpa = 1 << 2;
> > >  
> > >      /* recommended default value (~70 C) */
> > >      id->wctemp = cpu_to_le16(NVME_TEMPERATURE_WARNING);
> > > diff --git a/hw/block/nvme.h b/hw/block/nvme.h
> > > index 1518f32557a3..89b0aafa02a2 100644
> > > --- a/hw/block/nvme.h
> > > +++ b/hw/block/nvme.h
> > > @@ -109,6 +109,7 @@ typedef struct NvmeCtrl {
> > >      uint64_t    host_timestamp;                 /* Timestamp sent by the host */
> > >      uint64_t    timestamp_set_qemu_clock_ms;    /* QEMU clock time */
> > >      uint16_t    temperature;
> > > +    uint64_t    starttime_ms;
> > >  
> > >      NvmeNamespace   *namespaces;
> > >      NvmeSQueue      **sq;
> > > @@ -124,4 +125,13 @@ static inline uint64_t nvme_ns_nlbas(NvmeCtrl *n, NvmeNamespace *ns)
> > >      return n->ns_size >> nvme_ns_lbads(ns);
> > >  }
> > >  
> > > +static inline uint16_t nvme_cid(NvmeRequest *req)
> > > +{
> > > +    if (req) {
> > > +        return le16_to_cpu(req->cqe.cid);
> > > +    }
> > > +
> > > +    return 0xffff;
> > > +}
> > 
> > I see that you added command ID reporting to trace events you added,
> > which makes sense.
> > I think it would be nice later to add it to existing trace events where it makes sense.
> > 
> 
> Exactly. I'm doing that as I encounter it and it makes sense to have it
> in the patch.
OK, I don't mind.
> 
> > 
> > > +
> > >  #endif /* HW_NVME_H */
> > > diff --git a/hw/block/trace-events b/hw/block/trace-events
> > > index ade506ea2bb2..7da088479f39 100644
> > > --- a/hw/block/trace-events
> > > +++ b/hw/block/trace-events
> > > @@ -46,6 +46,7 @@ nvme_dev_getfeat_numq(int result) "get feature number of queues, result=%d"
> > >  nvme_dev_setfeat_numq(int reqcq, int reqsq, int gotcq, int gotsq) "requested cq_count=%d sq_count=%d, responding with cq_count=%d sq_count=%d"
> > >  nvme_dev_setfeat_timestamp(uint64_t ts) "set feature timestamp = 0x%"PRIx64""
> > >  nvme_dev_getfeat_timestamp(uint64_t ts) "get feature timestamp = 0x%"PRIx64""
> > > +nvme_dev_get_log(uint16_t cid, uint8_t lid, uint8_t rae, uint32_t len, uint64_t off) "cid %"PRIu16" lid 0x%"PRIx8" rae 0x%"PRIx8" len %"PRIu32" off %"PRIu64""
> > >  nvme_dev_mmio_intm_set(uint64_t data, uint64_t new_mask) "wrote MMIO, interrupt mask set, data=0x%"PRIx64", new_mask=0x%"PRIx64""
> > >  nvme_dev_mmio_intm_clr(uint64_t data, uint64_t new_mask) "wrote MMIO, interrupt mask clr, data=0x%"PRIx64", new_mask=0x%"PRIx64""
> > >  nvme_dev_mmio_cfg(uint64_t data) "wrote MMIO, config controller config=0x%"PRIx64""
> > > @@ -85,6 +86,7 @@ nvme_dev_err_invalid_create_cq_qflags(uint16_t qflags) "failed creating completi
> > >  nvme_dev_err_invalid_identify_cns(uint16_t cns) "identify, invalid cns=0x%"PRIx16""
> > >  nvme_dev_err_invalid_getfeat(int dw10) "invalid get features, dw10=0x%"PRIx32""
> > >  nvme_dev_err_invalid_setfeat(uint32_t dw10) "invalid set features, dw10=0x%"PRIx32""
> > > +nvme_dev_err_invalid_log_page(uint16_t cid, uint16_t lid) "cid %"PRIu16" lid 0x%"PRIx16""
> > >  nvme_dev_err_startfail_cq(void) "nvme_start_ctrl failed because there are non-admin completion queues"
> > >  nvme_dev_err_startfail_sq(void) "nvme_start_ctrl failed because there are non-admin submission queues"
> > >  nvme_dev_err_startfail_nbarasq(void) "nvme_start_ctrl failed because the admin submission queue address is null"
> > > diff --git a/include/block/nvme.h b/include/block/nvme.h
> > > index ff31cb32117c..9a6055adeb61 100644
> > > --- a/include/block/nvme.h
> > > +++ b/include/block/nvme.h
> > > @@ -515,7 +515,7 @@ enum NvmeSmartWarn {
> > >      NVME_SMART_FAILED_VOLATILE_MEDIA  = 1 << 4,
> > >  };
> > >  
> > > -enum LogIdentifier {
> > > +enum NvmeLogIdentifier {
> > >      NVME_LOG_ERROR_INFO     = 0x01,
> > >      NVME_LOG_SMART_INFO     = 0x02,
> > >      NVME_LOG_FW_SLOT_INFO   = 0x03,
> > 
> > Best regards,
> > 	Maxim Levitsky
> > 
> 
> 

Best regards,
	Maxim Levitsky