Re: [QEMU PATCH v4 10/10] cxl-mailbox-utils: 0x5605 - FMAPI Initiate DC Release

[Jonathan Cameron <Jonathan.Cameron@huawei.com>]

On Thu, 3 Jul 2025 04:21:25 +0000
Fan Ni <nifan.cxl@gmail.com> wrote:

> On Thu, Jun 26, 2025 at 10:23:33PM +0000, anisa.su887@gmail.com wrote:
> > From: Anisa Su <anisa.su@samsung.com>
> > 
> > FM DCD Management command 0x5605 implemented per CXL r3.2 Spec Section 7.6.7.6.6
> > 
> > Signed-off-by: Anisa Su <anisa.su@samsung.com>
> > ---  
> Minor comments inline ...
Hi Fan,


See below. I tweaked what you are commenting on in version I rebased and asked
Michael to consider picking up.

If you are happy with that, please give a tag on 
https://lore.kernel.org/qemu-devel/20250702160219.989731-12-Jonathan.Cameron@huawei.com/
> 
> >  hw/cxl/cxl-mailbox-utils.c | 79 ++++++++++++++++++++++++++++++++++++++
> >  1 file changed, 79 insertions(+)
> > 
> > diff --git a/hw/cxl/cxl-mailbox-utils.c b/hw/cxl/cxl-mailbox-utils.c
> > index 787eeaa7b9..87f9535d46 100644
> > --- a/hw/cxl/cxl-mailbox-utils.c
> > +++ b/hw/cxl/cxl-mailbox-utils.c
> > @@ -123,6 +123,7 @@ enum {
> >          #define SET_DC_REGION_CONFIG        0x2
> >          #define GET_DC_REGION_EXTENT_LIST   0x3
> >          #define INITIATE_DC_ADD             0x4
> > +        #define INITIATE_DC_RELEASE         0x5
> >  };
> >  
> >  /* CCI Message Format CXL r3.1 Figure 7-19 */
> > @@ -3638,6 +3639,77 @@ static CXLRetCode cmd_fm_initiate_dc_add(const struct cxl_cmd *cmd,
> >      }
> >  }
> >  
> > +#define CXL_EXTENT_REMOVAL_POLICY_MASK 0x0F
> > +#define CXL_FORCED_REMOVAL_MASK (1 << 4)
> > +/* CXL r3.2 Section 7.6.7.6.6 Initiate Dynamic Capacity Release (Opcode 5605h) */  
> 
> /* CXL r3.2 Section 7.6.7.6.6: Initiate Dynamic Capacity Release (Opcode 5605h) */
This one I fixed.  Noticed it because the line is also over 80 chars so now
formatted as

/*
 * CXL r3.2 Section 7.6.7.6.6:
 * Initiate Dynamic Capacity Release (Opcode 5605h) */
 */
> 
> Fan
> 
> > +static CXLRetCode cmd_fm_initiate_dc_release(const struct cxl_cmd *cmd,
> > +                                             uint8_t *payload_in,
> > +                                             size_t len_in,
> > +                                             uint8_t *payload_out,
> > +                                             size_t *len_out,
> > +                                             CXLCCI *cci)
> > +{
> > +    struct {
> > +        uint16_t host_id;
> > +        uint8_t flags;
> > +        uint8_t reg_num;
> > +        uint64_t length;
> > +        uint8_t tag[0x10];
> > +        uint32_t ext_count;
> > +        CXLDCExtentRaw extents[];
> > +    } QEMU_PACKED *in = (void *)payload_in;
> > +    CXLType3Dev *ct3d = CXL_TYPE3(cci->d);
> > +    int i, rc;
> > +
> > +    switch (in->flags & CXL_EXTENT_REMOVAL_POLICY_MASK) {
> > +        case CXL_EXTENT_REMOVAL_POLICY_PRESCRIPTIVE: {
> > +            CXLDCExtentList updated_list;
> > +            uint32_t updated_list_size;
> > +            g_autofree CXLUpdateDCExtentListInPl *list =
> > +                g_malloc0(sizeof(*list) +
> > +                    in->ext_count * sizeof(*list->updated_entries));
> > +
> > +            convert_raw_extents(in->extents, list, in->ext_count);
> > +            rc = cxl_detect_malformed_extent_list(ct3d, list);
> > +            if (rc) {
> > +                return rc;
> > +            }
> > +
> > +            /* Fail with Invalid PA if an extent is pending and Forced Removal
> > +             * flag not set
> > +             */
> > +            if (!(in->flags & CXL_FORCED_REMOVAL_MASK)) {
> > +                for (i = 0; i < in->ext_count; i++) {
> > +                    CXLDCExtentRaw ext = in->extents[i];
> > +                    /* Check requested extents don't overlap with pending extents. */
> > +                    if (cxl_extent_groups_overlaps_dpa_range(&ct3d->dc.extents_pending,
> > +                                                             ext.start_dpa, ext.len)) {
> > +                        return CXL_MBOX_INVALID_PA;
> > +                    }
> > +                }
> > +            }
> > +
> > +            rc = cxl_dc_extent_release_dry_run(ct3d,
> > +                                               list,
> > +                                               &updated_list,
> > +                                               &updated_list_size);
> > +            if (rc) {
> > +                return rc;
> > +            }
> > +            cxl_create_dc_event_records_for_extents(ct3d,
> > +                                                    DC_EVENT_RELEASE_CAPACITY,
> > +                                                    in->extents,
> > +                                                    in->ext_count);
> > +            return CXL_MBOX_SUCCESS;
> > +        }
> > +        default: {
> > +            qemu_log_mask(LOG_UNIMP,
> > +                "CXL extent removal policy not supported.\n");
> > +            return CXL_MBOX_INVALID_INPUT;
> > +        }
> > +    }
> > +}
> > +
> >  static const struct cxl_cmd cxl_cmd_set[256][256] = {
> >      [INFOSTAT][BACKGROUND_OPERATION_ABORT] = { "BACKGROUND_OPERATION_ABORT",
> >          cmd_infostat_bg_op_abort, 0, 0 },
> > @@ -3772,6 +3844,13 @@ static const struct cxl_cmd cxl_cmd_set_fm_dcd[256][256] = {
> >          CXL_MBOX_CONFIG_CHANGE_CXL_RESET |
> >          CXL_MBOX_IMMEDIATE_CONFIG_CHANGE |
> >          CXL_MBOX_IMMEDIATE_DATA_CHANGE) },
> > +    [FMAPI_DCD_MGMT][INITIATE_DC_RELEASE] = { "INIT_DC_RELEASE",
> > +        cmd_fm_initiate_dc_release, ~0,
> > +        (CXL_MBOX_CONFIG_CHANGE_COLD_RESET |
> > +         CXL_MBOX_CONFIG_CHANGE_CONV_RESET |
> > +         CXL_MBOX_CONFIG_CHANGE_CXL_RESET |
> > +         CXL_MBOX_IMMEDIATE_CONFIG_CHANGE |
> > +         CXL_MBOX_IMMEDIATE_DATA_CHANGE) },
> >  };
> >  
> >  /*
> > -- 
> > 2.47.2
> >   
>