drm/i915/gvt: Change the return type during command scan

Generally, there are 3 types of errors during command scan: a) some
commands might be unknown with EBADRQC;  b) some cmd access invalid
address with EFAULT; c) some unexpected force nonpriv cmd with EPERM.
later the healthy state can be judged through the return error.

v2:
- remove some internal i915 errors rating.  (Zhenyu)

v3:
- the healthy state is judged through the internal defined return
  error. (Zhenyu)
- force non priv cmd error can be ignored. (Kevin)

v4:
- reuse standard defined errno instead of recreate, e.g EBADRQC for
  unknown cmd, EFAULT for invalid address, EPERM for nonpriv. (Zhenyu)

v5:
- remove some irrelevant code for the patch.
- fix typo of vgpu_is_vm_unhealthy. (Zhenyu)

v6:
- move the healthy check and failsafe code into another patch. (Zhenyu)

v7:
- polish title and commit message. (Zhenyu)

Signed-off-by: fred gao <fred.gao@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>

diff --git a/drivers/gpu/drm/i915/gvt/cmd_parser.c b/drivers/gpu/drm/i915/gvt/cmd_parser.c
index 5b033c9..885cccf 100644 (file)
--- a/drivers/gpu/drm/i915/gvt/cmd_parser.c
+++ b/drivers/gpu/drm/i915/gvt/cmd_parser.c
@@ -825,7 +825,7 @@ static int force_nonpriv_reg_handler(struct parser_exec_state *s,
        if (!intel_gvt_in_force_nonpriv_whitelist(gvt, data)) {
                gvt_err("Unexpected forcenonpriv 0x%x LRI write, value=0x%x\n",
                        offset, data);
-               return -EINVAL;
+               return -EPERM;
        }
        return 0;
 }
@@ -839,7 +839,7 @@ static int cmd_reg_handler(struct parser_exec_state *s,
        if (offset + 4 > gvt->device_info.mmio_size) {
                gvt_vgpu_err("%s access to (%x) outside of MMIO range\n",
                                cmd, offset);
-               return -EINVAL;
+               return -EFAULT;
        }
 
        if (!intel_gvt_mmio_is_cmd_access(gvt, offset)) {
@@ -854,8 +854,8 @@ static int cmd_reg_handler(struct parser_exec_state *s,
        }
 
        if (is_force_nonpriv_mmio(offset) &&
-           force_nonpriv_reg_handler(s, offset, index))
-               return -EINVAL;
+               force_nonpriv_reg_handler(s, offset, index))
+               return -EPERM;
 
        if (offset == i915_mmio_reg_offset(DERRMR) ||
                offset == i915_mmio_reg_offset(FORCEWAKE_MT)) {
@@ -894,11 +894,14 @@ static int cmd_handler_lri(struct parser_exec_state *s)
                                        i915_mmio_reg_offset(DERRMR))
                                ret |= 0;
                        else
-                               ret |= (cmd_reg_inhibit(s, i)) ? -EINVAL : 0;
+                               ret |= (cmd_reg_inhibit(s, i)) ?
+                                       -EBADRQC : 0;
                }
                if (ret)
                        break;
                ret |= cmd_reg_handler(s, cmd_reg(s, i), i, "lri");
+               if (ret)
+                       break;
        }
        return ret;
 }
@@ -912,11 +915,15 @@ static int cmd_handler_lrr(struct parser_exec_state *s)
                if (IS_BROADWELL(s->vgpu->gvt->dev_priv))
                        ret |= ((cmd_reg_inhibit(s, i) ||
                                        (cmd_reg_inhibit(s, i + 1)))) ?
-                               -EINVAL : 0;
+                               -EBADRQC : 0;
                if (ret)
                        break;
                ret |= cmd_reg_handler(s, cmd_reg(s, i), i, "lrr-src");
+               if (ret)
+                       break;
                ret |= cmd_reg_handler(s, cmd_reg(s, i + 1), i, "lrr-dst");
+               if (ret)
+                       break;
        }
        return ret;
 }
@@ -934,15 +941,19 @@ static int cmd_handler_lrm(struct parser_exec_state *s)
 
        for (i = 1; i < cmd_len;) {
                if (IS_BROADWELL(gvt->dev_priv))
-                       ret |= (cmd_reg_inhibit(s, i)) ? -EINVAL : 0;
+                       ret |= (cmd_reg_inhibit(s, i)) ? -EBADRQC : 0;
                if (ret)
                        break;
                ret |= cmd_reg_handler(s, cmd_reg(s, i), i, "lrm");
+               if (ret)
+                       break;
                if (cmd_val(s, 0) & (1 << 22)) {
                        gma = cmd_gma(s, i + 1);
                        if (gmadr_bytes == 8)
                                gma |= (cmd_gma_hi(s, i + 2)) << 32;
                        ret |= cmd_address_audit(s, gma, sizeof(u32), false);
+                       if (ret)
+                               break;
                }
                i += gmadr_dw_number(s) + 1;
        }
@@ -958,11 +969,15 @@ static int cmd_handler_srm(struct parser_exec_state *s)
 
        for (i = 1; i < cmd_len;) {
                ret |= cmd_reg_handler(s, cmd_reg(s, i), i, "srm");
+               if (ret)
+                       break;
                if (cmd_val(s, 0) & (1 << 22)) {
                        gma = cmd_gma(s, i + 1);
                        if (gmadr_bytes == 8)
                                gma |= (cmd_gma_hi(s, i + 2)) << 32;
                        ret |= cmd_address_audit(s, gma, sizeof(u32), false);
+                       if (ret)
+                               break;
                }
                i += gmadr_dw_number(s) + 1;
        }
@@ -1116,7 +1131,7 @@ static int gen8_decode_mi_display_flip(struct parser_exec_state *s,
 
        v = (dword0 & GENMASK(21, 19)) >> 19;
        if (WARN_ON(v >= ARRAY_SIZE(gen8_plane_code)))
-               return -EINVAL;
+               return -EBADRQC;
 
        info->pipe = gen8_plane_code[v].pipe;
        info->plane = gen8_plane_code[v].plane;
@@ -1136,7 +1151,7 @@ static int gen8_decode_mi_display_flip(struct parser_exec_state *s,
                info->surf_reg = SPRSURF(info->pipe);
        } else {
                WARN_ON(1);
-               return -EINVAL;
+               return -EBADRQC;
        }
        return 0;
 }
@@ -1185,7 +1200,7 @@ static int skl_decode_mi_display_flip(struct parser_exec_state *s,
 
        default:
                gvt_vgpu_err("unknown plane code %d\n", plane);
-               return -EINVAL;
+               return -EBADRQC;
        }
 
        info->stride_val = (dword1 & GENMASK(15, 6)) >> 6;
@@ -1348,10 +1363,13 @@ static unsigned long get_gma_bb_from_cmd(struct parser_exec_state *s, int index)
 {
        unsigned long addr;
        unsigned long gma_high, gma_low;
-       int gmadr_bytes = s->vgpu->gvt->device_info.gmadr_bytes_in_cmd;
+       struct intel_vgpu *vgpu = s->vgpu;
+       int gmadr_bytes = vgpu->gvt->device_info.gmadr_bytes_in_cmd;
 
-       if (WARN_ON(gmadr_bytes != 4 && gmadr_bytes != 8))
+       if (WARN_ON(gmadr_bytes != 4 && gmadr_bytes != 8)) {
+               gvt_vgpu_err("invalid gma bytes %d\n", gmadr_bytes);
                return INTEL_GVT_INVALID_ADDR;
+       }
 
        gma_low = cmd_val(s, index) & BATCH_BUFFER_ADDR_MASK;
        if (gmadr_bytes == 4) {
@@ -1374,16 +1392,16 @@ static inline int cmd_address_audit(struct parser_exec_state *s,
        if (op_size > max_surface_size) {
                gvt_vgpu_err("command address audit fail name %s\n",
                        s->info->name);
-               return -EINVAL;
+               return -EFAULT;
        }
 
        if (index_mode) {
                if (guest_gma >= GTT_PAGE_SIZE / sizeof(u64)) {
-                       ret = -EINVAL;
+                       ret = -EFAULT;
                        goto err;
                }
        } else if (!intel_gvt_ggtt_validate_range(vgpu, guest_gma, op_size)) {
-               ret = -EINVAL;
+               ret = -EFAULT;
                goto err;
        }
 
@@ -1439,7 +1457,7 @@ static inline int unexpected_cmd(struct parser_exec_state *s)
 
        gvt_vgpu_err("Unexpected %s in command buffer!\n", s->info->name);
 
-       return -EINVAL;
+       return -EBADRQC;
 }
 
 static int cmd_handler_mi_semaphore_wait(struct parser_exec_state *s)
@@ -1588,22 +1606,26 @@ static int find_bb_size(struct parser_exec_state *s)
 
        /* get the start gm address of the batch buffer */
        gma = get_gma_bb_from_cmd(s, 1);
+       if (gma == INTEL_GVT_INVALID_ADDR)
+               return -EFAULT;
+
        cmd = cmd_val(s, 0);
 
        info = get_cmd_info(s->vgpu->gvt, cmd, s->ring_id);
        if (info == NULL) {
                gvt_vgpu_err("unknown cmd 0x%x, opcode=0x%x\n",
                                cmd, get_opcode(cmd, s->ring_id));
-               return -EINVAL;
+               return -EBADRQC;
        }
        do {
-               copy_gma_to_hva(s->vgpu, s->vgpu->gtt.ggtt_mm,
-                               gma, gma + 4, &cmd);
+               if (copy_gma_to_hva(s->vgpu, s->vgpu->gtt.ggtt_mm,
+                               gma, gma + 4, &cmd) < 0)
+                       return -EFAULT;
                info = get_cmd_info(s->vgpu->gvt, cmd, s->ring_id);
                if (info == NULL) {
                        gvt_vgpu_err("unknown cmd 0x%x, opcode=0x%x\n",
                                cmd, get_opcode(cmd, s->ring_id));
-                       return -EINVAL;
+                       return -EBADRQC;
                }
 
                if (info->opcode == OP_MI_BATCH_BUFFER_END) {
@@ -1634,11 +1656,13 @@ static int perform_bb_shadow(struct parser_exec_state *s)
 
        /* get the start gm address of the batch buffer */
        gma = get_gma_bb_from_cmd(s, 1);
+       if (gma == INTEL_GVT_INVALID_ADDR)
+               return -EFAULT;
 
        /* get the size of the batch buffer */
        bb_size = find_bb_size(s);
        if (bb_size < 0)
-               return -EINVAL;
+               return bb_size;
 
        /* allocate shadow batch buffer */
        entry_obj = kmalloc(sizeof(*entry_obj), GFP_KERNEL);
@@ -1710,13 +1734,13 @@ static int cmd_handler_mi_batch_buffer_start(struct parser_exec_state *s)
 
        if (s->buf_type == BATCH_BUFFER_2ND_LEVEL) {
                gvt_vgpu_err("Found MI_BATCH_BUFFER_START in 2nd level BB\n");
-               return -EINVAL;
+               return -EFAULT;
        }
 
        second_level = BATCH_BUFFER_2ND_LEVEL_BIT(cmd_val(s, 0)) == 1;
        if (second_level && (s->buf_type != BATCH_BUFFER_INSTRUCTION)) {
                gvt_vgpu_err("Jumping to 2nd level BB from RB is not allowed\n");
-               return -EINVAL;
+               return -EFAULT;
        }
 
        s->saved_buf_addr_type = s->buf_addr_type;
@@ -2430,7 +2454,7 @@ static int cmd_parser_exec(struct parser_exec_state *s)
        if (info == NULL) {
                gvt_vgpu_err("unknown cmd 0x%x, opcode=0x%x\n",
                                cmd, get_opcode(cmd, s->ring_id));
-               return -EINVAL;
+               return -EBADRQC;
        }
 
        s->info = info;
@@ -2465,6 +2489,10 @@ static inline bool gma_out_of_range(unsigned long gma,
                return (gma > gma_tail) && (gma < gma_head);
 }
 
+/* Keep the consistent return type, e.g EBADRQC for unknown
+ * cmd, EFAULT for invalid address, EPERM for nonpriv. later
+ * works as the input of VM healthy status.
+ */
 static int command_scan(struct parser_exec_state *s,
                unsigned long rb_head, unsigned long rb_tail,
                unsigned long rb_start, unsigned long rb_len)
@@ -2487,7 +2515,7 @@ static int command_scan(struct parser_exec_state *s,
                                        s->ip_gma, rb_start,
                                        gma_bottom);
                                parser_exec_state_dump(s);
-                               return -EINVAL;
+                               return -EFAULT;
                        }
                        if (gma_out_of_range(s->ip_gma, gma_head, gma_tail)) {
                                gvt_vgpu_err("ip_gma %lx out of range."

diff --git a/drivers/gpu/drm/i915/gvt/scheduler.c b/drivers/gpu/drm/i915/gvt/scheduler.c
index 7cb1cf4..0771b71 100644 (file)
--- a/drivers/gpu/drm/i915/gvt/scheduler.c
+++ b/drivers/gpu/drm/i915/gvt/scheduler.c
@@ -84,7 +84,7 @@ static int populate_shadow_context(struct intel_vgpu_workload *workload)
                                GTT_PAGE_SHIFT));
                if (context_gpa == INTEL_GVT_INVALID_ADDR) {
                        gvt_vgpu_err("Invalid guest context descriptor\n");
-                       return -EINVAL;
+                       return -EFAULT;
                }
 
                page = i915_gem_object_get_page(ctx_obj, LRC_HEADER_PAGES + i);