From 457c25e94adc47aa29e1e2349c2452bca3acac83 Mon Sep 17 00:00:00 2001
From: teoxoy <28601907+teoxoy@users.noreply.github.com>
Date: Mon, 9 Dec 2024 22:56:02 +0100
Subject: [PATCH] remove `BufferUses::STORAGE_WRITE_ONLY`, reverting part of
 0b6571a

The spec doesn't have write-only storage buffers.
---
 wgpu-core/src/conv.rs            |  2 +-
 wgpu-core/src/device/resource.rs | 11 +----------
 wgpu-hal/src/dx12/conv.rs        |  2 +-
 wgpu-hal/src/gles/queue.rs       |  4 +---
 wgpu-hal/src/lib.rs              |  2 --
 wgpu-hal/src/vulkan/conv.rs      | 18 ++++++------------
 6 files changed, 10 insertions(+), 29 deletions(-)

diff --git a/wgpu-core/src/conv.rs b/wgpu-core/src/conv.rs
index b114e9826e..dbf3adb2a6 100644
--- a/wgpu-core/src/conv.rs
+++ b/wgpu-core/src/conv.rs
@@ -82,7 +82,7 @@ pub fn map_buffer_usage(usage: wgt::BufferUsages) -> hal::BufferUses {
         usage.contains(wgt::BufferUsages::UNIFORM),
     );
     u.set(
-        hal::BufferUses::STORAGE_READ_WRITE,
+        hal::BufferUses::STORAGE_READ_ONLY | hal::BufferUses::STORAGE_READ_WRITE,
         usage.contains(wgt::BufferUsages::STORAGE),
     );
     u.set(
diff --git a/wgpu-core/src/device/resource.rs b/wgpu-core/src/device/resource.rs
index cf5ed7038b..403ced5263 100644
--- a/wgpu-core/src/device/resource.rs
+++ b/wgpu-core/src/device/resource.rs
@@ -521,16 +521,7 @@ impl Device {
             self.require_downlevel_flags(wgt::DownlevelFlags::INDIRECT_EXECUTION)?;
             // We are going to be reading from it, internally;
             // when validating the content of the buffer
-            if !usage.intersects(
-                hal::BufferUses::STORAGE_READ_ONLY | hal::BufferUses::STORAGE_READ_WRITE,
-            ) {
-                if usage.contains(hal::BufferUses::STORAGE_WRITE_ONLY) {
-                    usage |= hal::BufferUses::STORAGE_READ_WRITE;
-                    usage &= !hal::BufferUses::STORAGE_WRITE_ONLY;
-                } else {
-                    usage |= hal::BufferUses::STORAGE_READ_ONLY;
-                }
-            }
+            usage |= hal::BufferUses::STORAGE_READ_ONLY | hal::BufferUses::STORAGE_READ_WRITE;
         }
 
         if desc.mapped_at_creation {
diff --git a/wgpu-hal/src/dx12/conv.rs b/wgpu-hal/src/dx12/conv.rs
index 70ba83fa42..4d597af1db 100644
--- a/wgpu-hal/src/dx12/conv.rs
+++ b/wgpu-hal/src/dx12/conv.rs
@@ -128,7 +128,7 @@ pub fn map_buffer_usage_to_state(usage: crate::BufferUses) -> Direct3D12::D3D12_
     if usage.intersects(Bu::VERTEX | Bu::UNIFORM) {
         state |= Direct3D12::D3D12_RESOURCE_STATE_VERTEX_AND_CONSTANT_BUFFER;
     }
-    if usage.intersects(Bu::STORAGE_READ_WRITE | Bu::STORAGE_WRITE_ONLY) {
+    if usage.intersects(Bu::STORAGE_READ_WRITE) {
         state |= Direct3D12::D3D12_RESOURCE_STATE_UNORDERED_ACCESS;
     } else if usage.intersects(Bu::STORAGE_READ_ONLY) {
         state |= Direct3D12::D3D12_RESOURCE_STATE_PIXEL_SHADER_RESOURCE
diff --git a/wgpu-hal/src/gles/queue.rs b/wgpu-hal/src/gles/queue.rs
index 892e854b52..8896aa4ed0 100644
--- a/wgpu-hal/src/gles/queue.rs
+++ b/wgpu-hal/src/gles/queue.rs
@@ -1225,9 +1225,7 @@ impl super::Queue {
                     flags |= glow::BUFFER_UPDATE_BARRIER_BIT;
                 }
                 if usage.intersects(
-                    crate::BufferUses::STORAGE_READ_ONLY
-                        | crate::BufferUses::STORAGE_WRITE_ONLY
-                        | crate::BufferUses::STORAGE_READ_WRITE,
+                    crate::BufferUses::STORAGE_READ_ONLY | crate::BufferUses::STORAGE_READ_WRITE,
                 ) {
                     flags |= glow::SHADER_STORAGE_BARRIER_BIT;
                 }
diff --git a/wgpu-hal/src/lib.rs b/wgpu-hal/src/lib.rs
index d989f6dc7e..a398f079a7 100644
--- a/wgpu-hal/src/lib.rs
+++ b/wgpu-hal/src/lib.rs
@@ -1675,8 +1675,6 @@ bitflags::bitflags! {
         const UNIFORM = 1 << 6;
         /// A read-only storage buffer used in a bind group.
         const STORAGE_READ_ONLY = 1 << 7;
-        /// A write-only storage buffer used in a bind group.
-        const STORAGE_WRITE_ONLY = 1 << 8;
         /// A read-write buffer used in a bind group.
         const STORAGE_READ_WRITE = 1 << 8;
         /// The indirect or count buffer in a indirect draw or dispatch.
diff --git a/wgpu-hal/src/vulkan/conv.rs b/wgpu-hal/src/vulkan/conv.rs
index ce4aa410bf..05a06011d8 100644
--- a/wgpu-hal/src/vulkan/conv.rs
+++ b/wgpu-hal/src/vulkan/conv.rs
@@ -515,11 +515,9 @@ pub fn map_buffer_usage(usage: crate::BufferUses) -> vk::BufferUsageFlags {
     if usage.contains(crate::BufferUses::UNIFORM) {
         flags |= vk::BufferUsageFlags::UNIFORM_BUFFER;
     }
-    if usage.intersects(
-        crate::BufferUses::STORAGE_READ_ONLY
-            | crate::BufferUses::STORAGE_WRITE_ONLY
-            | crate::BufferUses::STORAGE_READ_WRITE,
-    ) {
+    if usage
+        .intersects(crate::BufferUses::STORAGE_READ_ONLY | crate::BufferUses::STORAGE_READ_WRITE)
+    {
         flags |= vk::BufferUsageFlags::STORAGE_BUFFER;
     }
     if usage.contains(crate::BufferUses::INDEX) {
@@ -573,17 +571,13 @@ pub fn map_buffer_usage_to_barrier(
         stages |= shader_stages;
         access |= vk::AccessFlags::UNIFORM_READ;
     }
-    if usage
-        .intersects(crate::BufferUses::STORAGE_READ_ONLY | crate::BufferUses::STORAGE_READ_WRITE)
-    {
+    if usage.intersects(crate::BufferUses::STORAGE_READ_ONLY) {
         stages |= shader_stages;
         access |= vk::AccessFlags::SHADER_READ;
     }
-    if usage
-        .intersects(crate::BufferUses::STORAGE_WRITE_ONLY | crate::BufferUses::STORAGE_READ_WRITE)
-    {
+    if usage.intersects(crate::BufferUses::STORAGE_READ_WRITE) {
         stages |= shader_stages;
-        access |= vk::AccessFlags::SHADER_WRITE;
+        access |= vk::AccessFlags::SHADER_READ | vk::AccessFlags::SHADER_WRITE;
     }
     if usage.contains(crate::BufferUses::INDEX) {
         stages |= vk::PipelineStageFlags::VERTEX_INPUT;