From 9f061763346787806990aabb57b1a1bfb69860ce Mon Sep 17 00:00:00 2001
From: Swastik-51 <Swastik-51@users.noreply.github.com>
Date: Fri, 9 Oct 2026 01:27:29 +0530
Subject: [PATCH] fix(agc): cache Linux describePages results

---
 .../Execution/src/GuestMemory.cpp             | 32 +++++++++++++------
 1 file changed, 22 insertions(+), 10 deletions(-)

diff --git a/core/libs/prx/libSceAgcDriver/Execution/src/GuestMemory.cpp b/core/libs/prx/libSceAgcDriver/Execution/src/GuestMemory.cpp
index de2fb32eb..77e3ac3e9 100644
--- a/core/libs/prx/libSceAgcDriver/Execution/src/GuestMemory.cpp
+++ b/core/libs/prx/libSceAgcDriver/Execution/src/GuestMemory.cpp
@@ -423,6 +423,17 @@ struct PageStates {
         arena.forget(address, bytes);
         image.forget(address, bytes);
     }
+
+    void record(std::uintptr_t base, std::uintptr_t regionEnd, bool readable, bool writable, std::uint64_t generation) {
+        for (PageSpan* span : {&arena, &image}) {
+            if (!readable || span->size == 0 || regionEnd <= span->base || base >= span->base + span->size) continue;
+            const std::uint8_t value = PageReadable | (writable ? PageWritable : 0u);
+            const auto first = std::max(base, span->base);
+            const auto last = std::min(regionEnd, span->base + span->size);
+            for (auto at = first; at < last; at += PageBytes) span->store(at, value);
+            if (GuestAllocations::GuestAllocationsGeneration_nid_postfix() != generation) span->forget(first, static_cast<std::size_t>(last - first));
+        }
+    }
 };
 
 PageStates& Pages() {
@@ -533,18 +544,12 @@ bool describePages(std::uintptr_t address, std::size_t bytes, Emit&& emit) {
         const bool committed = memory.State == MEM_COMMIT && (memory.Protect & (PAGE_GUARD | PAGE_NOACCESS)) == 0;
         const bool readable = committed && readableProtection(protection);
         const bool writable = readable && writableProtection(protection);
-        for (PageSpan* span : {&pages.arena, &pages.image}) {
-            if (!readable || span->size == 0 || regionEnd <= span->base || base >= span->base + span->size) continue;
-            const std::uint8_t value = PageReadable | (writable ? PageWritable : 0u);
-            const auto first = std::max(base, span->base);
-            const auto last = std::min(regionEnd, span->base + span->size);
-            for (auto at = first; at < last; at += PageBytes) span->store(at, value);
-            if (GuestAllocations::GuestAllocationsGeneration_nid_postfix() != generation) span->forget(first, static_cast<std::size_t>(last - first));
-        }
+        pages.record(base, regionEnd, readable, writable, generation);
         const auto next = std::min(end, regionEnd);
         if (!emit(PageRun{cursor, next, readable, writable})) return true;
         cursor = next;
 #else
+        const auto generation = GuestAllocations::GuestAllocationsGeneration_nid_postfix();
         if (const int fd = HostMapping::QueryFd(); fd >= 0) {
             procmap_query query{};
             query.size = sizeof(query);
@@ -558,9 +563,13 @@ bool describePages(std::uintptr_t address, std::size_t bytes, Emit&& emit) {
                     cursor = gapEnd;
                     continue;
                 }
+                const auto base = static_cast<std::uintptr_t>(query.vma_start);
+                const auto regionEnd = static_cast<std::uintptr_t>(query.vma_end);
                 const bool readable = (query.vma_flags & PROCMAP_QUERY_VMA_READABLE) != 0;
+                const bool writable = readable && (query.vma_flags & PROCMAP_QUERY_VMA_WRITABLE) != 0;
+                pages.record(base, regionEnd, readable, writable, generation);
                 const auto next = std::min<std::uintptr_t>(end, query.vma_end);
-                if (!emit(PageRun{cursor, next, readable, readable && (query.vma_flags & PROCMAP_QUERY_VMA_WRITABLE) != 0})) return true;
+                if (!emit(PageRun{cursor, next, readable, writable})) return true;
                 cursor = next;
                 continue;
             }
@@ -589,8 +598,11 @@ bool describePages(std::uintptr_t address, std::size_t bytes, Emit&& emit) {
                 found = true;
                 break;
             }
+            const bool readable = permissions[0] == 'r';
+            const bool writable = readable && permissions[1] == 'w';
+            pages.record(first, last, readable, writable, generation);
             const auto next = std::min(end, last);
-            if (!emit(PageRun{cursor, next, permissions[0] == 'r', permissions[0] == 'r' && permissions[1] == 'w'})) return true;
+            if (!emit(PageRun{cursor, next, readable, writable})) return true;
             cursor = next;
             found = true;
             break;