Re: [PATCH 2/9] drm/i915/gvt: Constify intel_gvt_gtt_pte_ops

From: Wang, Zhi A
Date: Fri Dec 10 2021 - 03:11:39 EST


On 12/4/2021 12:55 PM, Rikard Falkeborn wrote:
> These are never modified, so make them const to allow the compiler to
> put them in read-only memory.
>
> Signed-off-by: Rikard Falkeborn <rikard.falkeborn@xxxxxxxxx>
> ---
> drivers/gpu/drm/i915/gvt/gtt.c | 62 +++++++++++++++++-----------------
> drivers/gpu/drm/i915/gvt/gtt.h | 2 +-
> 2 files changed, 32 insertions(+), 32 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/gvt/gtt.c b/drivers/gpu/drm/i915/gvt/gtt.c
> index 6efa48727052..c8cd6bf28ea8 100644
> --- a/drivers/gpu/drm/i915/gvt/gtt.c
> +++ b/drivers/gpu/drm/i915/gvt/gtt.c
> @@ -499,7 +499,7 @@ DEFINE_PPGTT_GMA_TO_INDEX(gen8, l3_pdp, (gma >> 30 & 0x3));
> DEFINE_PPGTT_GMA_TO_INDEX(gen8, l4_pdp, (gma >> 30 & 0x1ff));
> DEFINE_PPGTT_GMA_TO_INDEX(gen8, pml4, (gma >> 39 & 0x1ff));
>
> -static struct intel_gvt_gtt_pte_ops gen8_gtt_pte_ops = {
> +static const struct intel_gvt_gtt_pte_ops gen8_gtt_pte_ops = {
> .get_entry = gtt_get_entry64,
> .set_entry = gtt_set_entry64,
> .clear_present = gtt_entry_clear_present,
> @@ -526,7 +526,7 @@ static const struct intel_gvt_gtt_gma_ops gen8_gtt_gma_ops = {
> };
>
> /* Update entry type per pse and ips bit. */
> -static void update_entry_type_for_real(struct intel_gvt_gtt_pte_ops *pte_ops,
> +static void update_entry_type_for_real(const struct intel_gvt_gtt_pte_ops *pte_ops,
> struct intel_gvt_gtt_entry *entry, bool ips)
> {
> switch (entry->type) {
> @@ -553,7 +553,7 @@ static void _ppgtt_get_root_entry(struct intel_vgpu_mm *mm,
> struct intel_gvt_gtt_entry *entry, unsigned long index,
> bool guest)
> {
> - struct intel_gvt_gtt_pte_ops *pte_ops = mm->vgpu->gvt->gtt.pte_ops;
> + const struct intel_gvt_gtt_pte_ops *pte_ops = mm->vgpu->gvt->gtt.pte_ops;
>
> GEM_BUG_ON(mm->type != INTEL_GVT_MM_PPGTT);
>
> @@ -580,7 +580,7 @@ static void _ppgtt_set_root_entry(struct intel_vgpu_mm *mm,
> struct intel_gvt_gtt_entry *entry, unsigned long index,
> bool guest)
> {
> - struct intel_gvt_gtt_pte_ops *pte_ops = mm->vgpu->gvt->gtt.pte_ops;
> + const struct intel_gvt_gtt_pte_ops *pte_ops = mm->vgpu->gvt->gtt.pte_ops;
>
> pte_ops->set_entry(guest ? mm->ppgtt_mm.guest_pdps :
> mm->ppgtt_mm.shadow_pdps,
> @@ -596,7 +596,7 @@ static inline void ppgtt_set_shadow_root_entry(struct intel_vgpu_mm *mm,
> static void ggtt_get_guest_entry(struct intel_vgpu_mm *mm,
> struct intel_gvt_gtt_entry *entry, unsigned long index)
> {
> - struct intel_gvt_gtt_pte_ops *pte_ops = mm->vgpu->gvt->gtt.pte_ops;
> + const struct intel_gvt_gtt_pte_ops *pte_ops = mm->vgpu->gvt->gtt.pte_ops;
>
> GEM_BUG_ON(mm->type != INTEL_GVT_MM_GGTT);
>
> @@ -608,7 +608,7 @@ static void ggtt_get_guest_entry(struct intel_vgpu_mm *mm,
> static void ggtt_set_guest_entry(struct intel_vgpu_mm *mm,
> struct intel_gvt_gtt_entry *entry, unsigned long index)
> {
> - struct intel_gvt_gtt_pte_ops *pte_ops = mm->vgpu->gvt->gtt.pte_ops;
> + const struct intel_gvt_gtt_pte_ops *pte_ops = mm->vgpu->gvt->gtt.pte_ops;
>
> GEM_BUG_ON(mm->type != INTEL_GVT_MM_GGTT);
>
> @@ -619,7 +619,7 @@ static void ggtt_set_guest_entry(struct intel_vgpu_mm *mm,
> static void ggtt_get_host_entry(struct intel_vgpu_mm *mm,
> struct intel_gvt_gtt_entry *entry, unsigned long index)
> {
> - struct intel_gvt_gtt_pte_ops *pte_ops = mm->vgpu->gvt->gtt.pte_ops;
> + const struct intel_gvt_gtt_pte_ops *pte_ops = mm->vgpu->gvt->gtt.pte_ops;
>
> GEM_BUG_ON(mm->type != INTEL_GVT_MM_GGTT);
>
> @@ -629,7 +629,7 @@ static void ggtt_get_host_entry(struct intel_vgpu_mm *mm,
> static void ggtt_set_host_entry(struct intel_vgpu_mm *mm,
> struct intel_gvt_gtt_entry *entry, unsigned long index)
> {
> - struct intel_gvt_gtt_pte_ops *pte_ops = mm->vgpu->gvt->gtt.pte_ops;
> + const struct intel_gvt_gtt_pte_ops *pte_ops = mm->vgpu->gvt->gtt.pte_ops;
> unsigned long offset = index;
>
> GEM_BUG_ON(mm->type != INTEL_GVT_MM_GGTT);
> @@ -655,7 +655,7 @@ static inline int ppgtt_spt_get_entry(
> bool guest)
> {
> struct intel_gvt *gvt = spt->vgpu->gvt;
> - struct intel_gvt_gtt_pte_ops *ops = gvt->gtt.pte_ops;
> + const struct intel_gvt_gtt_pte_ops *ops = gvt->gtt.pte_ops;
> int ret;
>
> e->type = get_entry_type(type);
> @@ -684,7 +684,7 @@ static inline int ppgtt_spt_set_entry(
> bool guest)
> {
> struct intel_gvt *gvt = spt->vgpu->gvt;
> - struct intel_gvt_gtt_pte_ops *ops = gvt->gtt.pte_ops;
> + const struct intel_gvt_gtt_pte_ops *ops = gvt->gtt.pte_ops;
>
> if (WARN(!gtt_type_is_entry(e->type), "invalid entry type\n"))
> return -EINVAL;
> @@ -947,7 +947,7 @@ static int ppgtt_invalidate_spt_by_shadow_entry(struct intel_vgpu *vgpu,
> struct intel_gvt_gtt_entry *e)
> {
> struct drm_i915_private *i915 = vgpu->gvt->gt->i915;
> - struct intel_gvt_gtt_pte_ops *ops = vgpu->gvt->gtt.pte_ops;
> + const struct intel_gvt_gtt_pte_ops *ops = vgpu->gvt->gtt.pte_ops;
> struct intel_vgpu_ppgtt_spt *s;
> enum intel_gvt_gtt_type cur_pt_type;
>
> @@ -984,7 +984,7 @@ static inline void ppgtt_invalidate_pte(struct intel_vgpu_ppgtt_spt *spt,
> struct intel_gvt_gtt_entry *entry)
> {
> struct intel_vgpu *vgpu = spt->vgpu;
> - struct intel_gvt_gtt_pte_ops *ops = vgpu->gvt->gtt.pte_ops;
> + const struct intel_gvt_gtt_pte_ops *ops = vgpu->gvt->gtt.pte_ops;
> unsigned long pfn;
> int type;
>
> @@ -1072,7 +1072,7 @@ static int ppgtt_populate_spt(struct intel_vgpu_ppgtt_spt *spt);
> static struct intel_vgpu_ppgtt_spt *ppgtt_populate_spt_by_guest_entry(
> struct intel_vgpu *vgpu, struct intel_gvt_gtt_entry *we)
> {
> - struct intel_gvt_gtt_pte_ops *ops = vgpu->gvt->gtt.pte_ops;
> + const struct intel_gvt_gtt_pte_ops *ops = vgpu->gvt->gtt.pte_ops;
> struct intel_vgpu_ppgtt_spt *spt = NULL;
> bool ips = false;
> int ret;
> @@ -1136,7 +1136,7 @@ static struct intel_vgpu_ppgtt_spt *ppgtt_populate_spt_by_guest_entry(
> static inline void ppgtt_generate_shadow_entry(struct intel_gvt_gtt_entry *se,
> struct intel_vgpu_ppgtt_spt *s, struct intel_gvt_gtt_entry *ge)
> {
> - struct intel_gvt_gtt_pte_ops *ops = s->vgpu->gvt->gtt.pte_ops;
> + const struct intel_gvt_gtt_pte_ops *ops = s->vgpu->gvt->gtt.pte_ops;
>
> se->type = ge->type;
> se->val64 = ge->val64;
> @@ -1159,7 +1159,7 @@ static inline void ppgtt_generate_shadow_entry(struct intel_gvt_gtt_entry *se,
> static int is_2MB_gtt_possible(struct intel_vgpu *vgpu,
> struct intel_gvt_gtt_entry *entry)
> {
> - struct intel_gvt_gtt_pte_ops *ops = vgpu->gvt->gtt.pte_ops;
> + const struct intel_gvt_gtt_pte_ops *ops = vgpu->gvt->gtt.pte_ops;
> unsigned long pfn;
>
> if (!HAS_PAGE_SIZES(vgpu->gvt->gt->i915, I915_GTT_PAGE_SIZE_2M))
> @@ -1176,7 +1176,7 @@ static int split_2MB_gtt_entry(struct intel_vgpu *vgpu,
> struct intel_vgpu_ppgtt_spt *spt, unsigned long index,
> struct intel_gvt_gtt_entry *se)
> {
> - struct intel_gvt_gtt_pte_ops *ops = vgpu->gvt->gtt.pte_ops;
> + const struct intel_gvt_gtt_pte_ops *ops = vgpu->gvt->gtt.pte_ops;
> struct intel_vgpu_ppgtt_spt *sub_spt;
> struct intel_gvt_gtt_entry sub_se;
> unsigned long start_gfn;
> @@ -1223,7 +1223,7 @@ static int split_64KB_gtt_entry(struct intel_vgpu *vgpu,
> struct intel_vgpu_ppgtt_spt *spt, unsigned long index,
> struct intel_gvt_gtt_entry *se)
> {
> - struct intel_gvt_gtt_pte_ops *ops = vgpu->gvt->gtt.pte_ops;
> + const struct intel_gvt_gtt_pte_ops *ops = vgpu->gvt->gtt.pte_ops;
> struct intel_gvt_gtt_entry entry = *se;
> unsigned long start_gfn;
> dma_addr_t dma_addr;
> @@ -1254,7 +1254,7 @@ static int ppgtt_populate_shadow_entry(struct intel_vgpu *vgpu,
> struct intel_vgpu_ppgtt_spt *spt, unsigned long index,
> struct intel_gvt_gtt_entry *ge)
> {
> - struct intel_gvt_gtt_pte_ops *pte_ops = vgpu->gvt->gtt.pte_ops;
> + const struct intel_gvt_gtt_pte_ops *pte_ops = vgpu->gvt->gtt.pte_ops;
> struct intel_gvt_gtt_entry se = *ge;
> unsigned long gfn, page_size = PAGE_SIZE;
> dma_addr_t dma_addr;
> @@ -1308,7 +1308,7 @@ static int ppgtt_populate_spt(struct intel_vgpu_ppgtt_spt *spt)
> {
> struct intel_vgpu *vgpu = spt->vgpu;
> struct intel_gvt *gvt = vgpu->gvt;
> - struct intel_gvt_gtt_pte_ops *ops = gvt->gtt.pte_ops;
> + const struct intel_gvt_gtt_pte_ops *ops = gvt->gtt.pte_ops;
> struct intel_vgpu_ppgtt_spt *s;
> struct intel_gvt_gtt_entry se, ge;
> unsigned long gfn, i;
> @@ -1351,7 +1351,7 @@ static int ppgtt_handle_guest_entry_removal(struct intel_vgpu_ppgtt_spt *spt,
> struct intel_gvt_gtt_entry *se, unsigned long index)
> {
> struct intel_vgpu *vgpu = spt->vgpu;
> - struct intel_gvt_gtt_pte_ops *ops = vgpu->gvt->gtt.pte_ops;
> + const struct intel_gvt_gtt_pte_ops *ops = vgpu->gvt->gtt.pte_ops;
> int ret;
>
> trace_spt_guest_change(spt->vgpu->id, "remove", spt,
> @@ -1432,7 +1432,7 @@ static int sync_oos_page(struct intel_vgpu *vgpu,
> {
> const struct intel_gvt_device_info *info = &vgpu->gvt->device_info;
> struct intel_gvt *gvt = vgpu->gvt;
> - struct intel_gvt_gtt_pte_ops *ops = gvt->gtt.pte_ops;
> + const struct intel_gvt_gtt_pte_ops *ops = gvt->gtt.pte_ops;
> struct intel_vgpu_ppgtt_spt *spt = oos_page->spt;
> struct intel_gvt_gtt_entry old, new;
> int index;
> @@ -1603,7 +1603,7 @@ static int ppgtt_handle_guest_write_page_table(
> {
> struct intel_vgpu *vgpu = spt->vgpu;
> int type = spt->shadow_page.type;
> - struct intel_gvt_gtt_pte_ops *ops = vgpu->gvt->gtt.pte_ops;
> + const struct intel_gvt_gtt_pte_ops *ops = vgpu->gvt->gtt.pte_ops;
> struct intel_gvt_gtt_entry old_se;
> int new_present;
> int i, ret;
> @@ -1720,7 +1720,7 @@ static int ppgtt_handle_guest_write_page_table_bytes(
> u64 pa, void *p_data, int bytes)
> {
> struct intel_vgpu *vgpu = spt->vgpu;
> - struct intel_gvt_gtt_pte_ops *ops = vgpu->gvt->gtt.pte_ops;
> + const struct intel_gvt_gtt_pte_ops *ops = vgpu->gvt->gtt.pte_ops;
> const struct intel_gvt_device_info *info = &vgpu->gvt->device_info;
> struct intel_gvt_gtt_entry we, se;
> unsigned long index;
> @@ -1785,7 +1785,7 @@ static void invalidate_ppgtt_mm(struct intel_vgpu_mm *mm)
> struct intel_vgpu *vgpu = mm->vgpu;
> struct intel_gvt *gvt = vgpu->gvt;
> struct intel_gvt_gtt *gtt = &gvt->gtt;
> - struct intel_gvt_gtt_pte_ops *ops = gtt->pte_ops;
> + const struct intel_gvt_gtt_pte_ops *ops = gtt->pte_ops;
> struct intel_gvt_gtt_entry se;
> int index;
>
> @@ -1815,7 +1815,7 @@ static int shadow_ppgtt_mm(struct intel_vgpu_mm *mm)
> struct intel_vgpu *vgpu = mm->vgpu;
> struct intel_gvt *gvt = vgpu->gvt;
> struct intel_gvt_gtt *gtt = &gvt->gtt;
> - struct intel_gvt_gtt_pte_ops *ops = gtt->pte_ops;
> + const struct intel_gvt_gtt_pte_ops *ops = gtt->pte_ops;
> struct intel_vgpu_ppgtt_spt *spt;
> struct intel_gvt_gtt_entry ge, se;
> int index, ret;
> @@ -2067,7 +2067,7 @@ static inline int ppgtt_get_next_level_entry(struct intel_vgpu_mm *mm,
> struct intel_gvt_gtt_entry *e, unsigned long index, bool guest)
> {
> struct intel_vgpu *vgpu = mm->vgpu;
> - struct intel_gvt_gtt_pte_ops *ops = vgpu->gvt->gtt.pte_ops;
> + const struct intel_gvt_gtt_pte_ops *ops = vgpu->gvt->gtt.pte_ops;
> struct intel_vgpu_ppgtt_spt *s;
>
> s = intel_vgpu_find_spt_by_mfn(vgpu, ops->get_pfn(e));
> @@ -2096,7 +2096,7 @@ unsigned long intel_vgpu_gma_to_gpa(struct intel_vgpu_mm *mm, unsigned long gma)
> {
> struct intel_vgpu *vgpu = mm->vgpu;
> struct intel_gvt *gvt = vgpu->gvt;
> - struct intel_gvt_gtt_pte_ops *pte_ops = gvt->gtt.pte_ops;
> + const struct intel_gvt_gtt_pte_ops *pte_ops = gvt->gtt.pte_ops;
> const struct intel_gvt_gtt_gma_ops *gma_ops = gvt->gtt.gma_ops;
> unsigned long gpa = INTEL_GVT_INVALID_ADDR;
> unsigned long gma_index[4];
> @@ -2221,7 +2221,7 @@ int intel_vgpu_emulate_ggtt_mmio_read(struct intel_vgpu *vgpu, unsigned int off,
> static void ggtt_invalidate_pte(struct intel_vgpu *vgpu,
> struct intel_gvt_gtt_entry *entry)
> {
> - struct intel_gvt_gtt_pte_ops *pte_ops = vgpu->gvt->gtt.pte_ops;
> + const struct intel_gvt_gtt_pte_ops *pte_ops = vgpu->gvt->gtt.pte_ops;
> unsigned long pfn;
>
> pfn = pte_ops->get_pfn(entry);
> @@ -2236,7 +2236,7 @@ static int emulate_ggtt_mmio_write(struct intel_vgpu *vgpu, unsigned int off,
> struct intel_gvt *gvt = vgpu->gvt;
> const struct intel_gvt_device_info *info = &gvt->device_info;
> struct intel_vgpu_mm *ggtt_mm = vgpu->gtt.ggtt_mm;
> - struct intel_gvt_gtt_pte_ops *ops = gvt->gtt.pte_ops;
> + const struct intel_gvt_gtt_pte_ops *ops = gvt->gtt.pte_ops;
> unsigned long g_gtt_index = off >> info->gtt_entry_size_shift;
> unsigned long gma, gfn;
> struct intel_gvt_gtt_entry e = {.val64 = 0, .type = GTT_TYPE_GGTT_PTE};
> @@ -2391,7 +2391,7 @@ static int alloc_scratch_pages(struct intel_vgpu *vgpu,
> {
> struct drm_i915_private *i915 = vgpu->gvt->gt->i915;
> struct intel_vgpu_gtt *gtt = &vgpu->gtt;
> - struct intel_gvt_gtt_pte_ops *ops = vgpu->gvt->gtt.pte_ops;
> + const struct intel_gvt_gtt_pte_ops *ops = vgpu->gvt->gtt.pte_ops;
> int page_entry_num = I915_GTT_PAGE_SIZE >>
> vgpu->gvt->device_info.gtt_entry_size_shift;
> void *scratch_pt;
> @@ -2822,7 +2822,7 @@ void intel_vgpu_invalidate_ppgtt(struct intel_vgpu *vgpu)
> void intel_vgpu_reset_ggtt(struct intel_vgpu *vgpu, bool invalidate_old)
> {
> struct intel_gvt *gvt = vgpu->gvt;
> - struct intel_gvt_gtt_pte_ops *pte_ops = vgpu->gvt->gtt.pte_ops;
> + const struct intel_gvt_gtt_pte_ops *pte_ops = vgpu->gvt->gtt.pte_ops;
> struct intel_gvt_gtt_entry entry = {.type = GTT_TYPE_GGTT_PTE};
> struct intel_gvt_gtt_entry old_entry;
> u32 index;
> diff --git a/drivers/gpu/drm/i915/gvt/gtt.h b/drivers/gpu/drm/i915/gvt/gtt.h
> index d0d598322404..a3b0f59ec8bd 100644
> --- a/drivers/gpu/drm/i915/gvt/gtt.h
> +++ b/drivers/gpu/drm/i915/gvt/gtt.h
> @@ -91,7 +91,7 @@ struct intel_gvt_gtt_gma_ops {
> };
>
> struct intel_gvt_gtt {
> - struct intel_gvt_gtt_pte_ops *pte_ops;
> + const struct intel_gvt_gtt_pte_ops *pte_ops;
> const struct intel_gvt_gtt_gma_ops *gma_ops;
> int (*mm_alloc_page_table)(struct intel_vgpu_mm *mm);
> void (*mm_free_page_table)(struct intel_vgpu_mm *mm);

Reviewed-by: Zhi Wang <zhi.a.wang@xxxxxxxxx>