From: Fan Ni <ni...@outlook.com>
Not all dpa range in the dc regions is valid to access until an extent
covering the range has been added. Add a bitmap for each region to
record whether a dc block in the region has been backed by dc extent.
For the bitmap, a bit in the bitmap represents a dc block. When a dc
extent is added, all the bits of the blocks in the extent will be set,
which will be cleared when the extent is released.
Signed-off-by: Fan Ni <fan...@samsung.com>
---
hw/mem/cxl_type3.c | 155 ++++++++++++++++++++++++++++++++++++
include/hw/cxl/cxl_device.h | 1 +
2 files changed, 156 insertions(+)
diff --git a/hw/mem/cxl_type3.c b/hw/mem/cxl_type3.c
index cb1f9182e6..e673287804 100644
--- a/hw/mem/cxl_type3.c
+++ b/hw/mem/cxl_type3.c
@@ -787,13 +787,37 @@ static int cxl_create_dc_regions(CXLType3Dev *ct3d)
/* dsmad_handle is set when creating cdat table entries */
region->flags = 0;
+ region->blk_bitmap = bitmap_new(region->len / region->block_size);
+ if (!region->blk_bitmap) {
+ break;
+ }
+
region_base += region->len;
}
+
+ if (i < ct3d->dc.num_regions) {
+ while (--i >= 0) {
+ g_free(ct3d->dc.regions[i].blk_bitmap);
+ }
+ return -1;
+ }
+
QTAILQ_INIT(&ct3d->dc.extents);
return 0;
}
+static void cxl_destroy_dc_regions(CXLType3Dev *ct3d)
+{
+ int i;
+ struct CXLDCD_Region *region;
+
+ for (i = 0; i < ct3d->dc.num_regions; i++) {
+ region = &ct3d->dc.regions[i];
+ g_free(region->blk_bitmap);
+ }
+}
+
static bool cxl_setup_memory(CXLType3Dev *ct3d, Error **errp)
{
DeviceState *ds = DEVICE(ct3d);
@@ -1021,6 +1045,7 @@ err_free_special_ops:
g_free(regs->special_ops);
err_address_space_free:
if (ct3d->dc.host_dc) {
+ cxl_destroy_dc_regions(ct3d);
address_space_destroy(&ct3d->dc.host_dc_as);
}
if (ct3d->hostpmem) {
@@ -1043,6 +1068,7 @@ static void ct3_exit(PCIDevice *pci_dev)
spdm_sock_fini(ct3d->doe_spdm.socket);
g_free(regs->special_ops);
if (ct3d->dc.host_dc) {
+ cxl_destroy_dc_regions(ct3d);
address_space_destroy(&ct3d->dc.host_dc_as);
}
if (ct3d->hostpmem) {
@@ -1053,6 +1079,110 @@ static void ct3_exit(PCIDevice *pci_dev)
}
}
+/*
+ * This function will marked the dpa range [dpa, dap + len) to be backed and
+ * accessible, this happens when a dc extent is added and accepted by the
+ * host.
+ */
+static void set_region_block_backed(CXLType3Dev *ct3d, uint64_t dpa,
+ uint64_t len)
+{
+ int i;
+ CXLDCD_Region *region = &ct3d->dc.regions[0];
+
+ if (dpa < region->base
+ || dpa >= region->base + ct3d->dc.total_capacity)
+ return;
+
+ /*
+ * spec 3.0 9.13.3: Regions are used in increasing-DPA order, with
+ * Region 0 being used for the lowest DPA of Dynamic Capacity and
+ * Region 7 for the highest DPA.
+ * So we check from the last region to find where the dpa belongs.
+ * access across multiple regions is not allowed.
+ **/
+ for (i = ct3d->dc.num_regions - 1; i >= 0; i--) {
+ region = &ct3d->dc.regions[i];
+ if (dpa >= region->base) {
+ break;
+ }
+ }
+
+ bitmap_set(region->blk_bitmap, (dpa - region->base) / region->block_size,
+ len / region->block_size);
+}
+
+/*
+ * This function check whether a dpa range [dpa, dpa + len) has been backed
+ * with dc extents, used when validating read/write to dc regions
+ */
+static bool test_region_block_backed(CXLType3Dev *ct3d, uint64_t dpa,
+ uint64_t len)
+{
+ int i;
+ CXLDCD_Region *region = &ct3d->dc.regions[0];
+ uint64_t nbits;
+ long nr;
+
+ if (dpa < region->base
+ || dpa >= region->base + ct3d->dc.total_capacity)
+ return false;
+
+ /*
+ * spec 3.0 9.13.3: Regions are used in increasing-DPA order, with
+ * Region 0 being used for the lowest DPA of Dynamic Capacity and
+ * Region 7 for the highest DPA.
+ * So we check from the last region to find where the dpa belongs.
+ * access across multiple regions is not allowed.
+ */
+ for (i = ct3d->dc.num_regions - 1; i >= 0; i--) {
+ region = &ct3d->dc.regions[i];
+ if (dpa >= region->base) {
+ break;
+ }
+ }
+
+ nr = (dpa - region->base) / region->block_size;
+ nbits = len / region->block_size;
+ return find_next_zero_bit(region->blk_bitmap, nbits, nr) >= nr + nbits;
+}
+
+/*
+ * This function will marked the dpa range [dpa, dap + len) to be unbacked and
+ * inaccessible, this happens when a dc extent is added and accepted by the
+ * host.
+ */
+static void clear_region_block_backed(CXLType3Dev *ct3d, uint64_t dpa,
+ uint64_t len)
+{
+ int i;
+ CXLDCD_Region *region = &ct3d->dc.regions[0];
+ uint64_t nbits;
+ long nr;
+
+ if (dpa < region->base
+ || dpa >= region->base + ct3d->dc.total_capacity)
+ return;
+
+ /*
+ * spec 3.0 9.13.3: Regions are used in increasing-DPA order, with
+ * Region 0 being used for the lowest DPA of Dynamic Capacity and
+ * Region 7 for the highest DPA.
+ * So we check from the last region to find where the dpa belongs.
+ * access across multiple regions is not allowed.
+ */
+ for (i = ct3d->dc.num_regions - 1; i >= 0; i--) {
+ region = &ct3d->dc.regions[i];
+ if (dpa >= region->base) {
+ break;
+ }
+ }
+
+ nr = (dpa - region->base) / region->block_size;
+ nbits = len / region->block_size;
+ bitmap_clear(region->blk_bitmap, nr, nbits);
+}
+
static bool cxl_type3_dpa(CXLType3Dev *ct3d, hwaddr host_addr, uint64_t *dpa)
{
uint32_t *cache_mem = ct3d->cxl_cstate.crb.cache_mem_registers;
@@ -1145,6 +1275,10 @@ static int cxl_type3_hpa_to_as_and_dpa(CXLType3Dev *ct3d,
*as = &ct3d->hostpmem_as;
*dpa_offset -= vmr_size;
} else {
+ if (!test_region_block_backed(ct3d, *dpa_offset, size)) {
+ return -ENODEV;
+ }
+
*as = &ct3d->dc.host_dc_as;
*dpa_offset -= (vmr_size + pmr_size);
}
@@ -1938,6 +2072,27 @@ static void qmp_cxl_process_dynamic_capacity_event(const
char *path,
}
g_free(extents);
+
+ /* Another choice is to do the set/clear after getting mailbox response*/
+ list = records;
+ while (list) {
+ dpa = list->value->dpa * 1024 * 1024;
+ len = list->value->len * 1024 * 1024;
+ rid = list->value->region_id;
+
+ switch (type) {
+ case DC_EVENT_ADD_CAPACITY:
+ set_region_block_backed(dcd, dpa, len);
+ break;
+ case DC_EVENT_RELEASE_CAPACITY:
+ clear_region_block_backed(dcd, dpa, len);
+ break;
+ default:
+ error_setg(errp, "DC event type not handled yet");
+ break;
+ }
+ list = list->next;
+ }
}
void qmp_cxl_add_dynamic_capacity_event(const char *path,
diff --git a/include/hw/cxl/cxl_device.h b/include/hw/cxl/cxl_device.h
index 5bf1dd4024..40ae96d824 100644
--- a/include/hw/cxl/cxl_device.h
+++ b/include/hw/cxl/cxl_device.h
@@ -411,6 +411,7 @@ typedef struct CXLDCD_Region {
uint64_t block_size;
uint32_t dsmadhandle;
uint8_t flags;
+ unsigned long *blk_bitmap;
} CXLDCD_Region;
struct CXLType3Dev {
--
2.39.2
