Kernel: Allow release of a specific amount of of clean pages

Previously, we could only release *all* clean pages. This patch makes it possible to release a specific amount of clean pages. If the attempted number of pages to release is more than the amount of clean pages, all clean pages will be released.
Author: https://github.com/dylanbobb Commit: 09d0fae2c6 Pull-request: https://github.com/SerenityOS/serenity/pull/14867 Reviewed-by: https://github.com/AtkinsSJ Reviewed-by: https://github.com/circl-lastname
2025-06-25 19:51:59 +00:00 · 2022-08-14 23:05:42 -04:00 · 2022-08-14 23:05:42 -04:00 · 09d0fae2c6 · 2024-07-17 08:13:21 +09:00
commit 09d0fae2c6
parent 072dde9387
2 changed files with 20 additions and 0 deletions
--- a/Kernel/Memory/InodeVMObject.cpp
+++ b/Kernel/Memory/InodeVMObject.cpp
@ -67,6 +67,25 @@ int InodeVMObject::release_all_clean_pages()
    return count;
 }

+int InodeVMObject::try_release_clean_pages(int page_amount)
+{
+    SpinlockLocker locker(m_lock);
+
+    int count = 0;
+    for (size_t i = 0; i < page_count() && count < page_amount; ++i) {
+        if (!m_dirty_pages.get(i) && m_physical_pages[i]) {
+            m_physical_pages[i] = nullptr;
+            ++count;
+        }
+    }
+    if (count) {
+        for_each_region([](auto& region) {
+            region.remap();
+        });
+    }
+    return count;
+}
+
 u32 InodeVMObject::writable_mappings() const
 {
    u32 count = 0;