[libc-commits] [libc] [libc] adjust linux's `mman.h` definitions (PR #79652)

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llvmbot wrote:


<!--LLVM PR SUMMARY COMMENT-->

@llvm/pr-subscribers-libc

Author: Schrodinger ZHU Yifan (SchrodingerZhu)

<details>
<summary>Changes</summary>

Use definitions from `<linux/mman.h>` to dispatch arch-specific flag values.
For example, `MCL_CURRENT/MCL_FUTURE/MCL_ONFAULT` are different on different architectures.

---
Full diff: https://github.com/llvm/llvm-project/pull/79652.diff


1 Files Affected:

- (modified) libc/include/llvm-libc-macros/linux/sys-mman-macros.h (+6-68) 


``````````diff
diff --git a/libc/include/llvm-libc-macros/linux/sys-mman-macros.h b/libc/include/llvm-libc-macros/linux/sys-mman-macros.h
index 1925c3c7cd3da09..15bd46824f9da57 100644
--- a/libc/include/llvm-libc-macros/linux/sys-mman-macros.h
+++ b/libc/include/llvm-libc-macros/linux/sys-mman-macros.h
@@ -9,80 +9,18 @@
 #ifndef __LLVM_LIBC_MACROS_LINUX_SYS_MMAN_MACROS_H
 #define __LLVM_LIBC_MACROS_LINUX_SYS_MMAN_MACROS_H
 
-// Memory protection flags. (mmap, munmap, mprotect)
-#define PROT_NONE 0x0
-#define PROT_READ 0x1
-#define PROT_WRITE 0x2
-#define PROT_EXEC 0x4
-// These protection flags are only valid for mprotect.
-#define PROT_GROWSUP 0x1000000
-#define PROT_GROWSDOWN 0x2000000
+// Use definitions from <linux/mman.h> to dispatch arch-specific flag values.
+// For example, MCL_CURRENT/MCL_FUTURE/MCL_ONFAULT are different on different
+// architectures.
+#include <linux/mman.h>
 
-// Memory mapping flags. (mmap, munmap)
+// Some posix standard flags are not defined in linux/mman.h.
+// Posix mmap flags.
 #define MAP_FAILED ((void *)-1)
-// These are the sharing types, and exactly one of these must be set.
-#define MAP_FILE 0x0 // Compatibility flag. Ignored.
-#define MAP_SHARED 0x1
-#define MAP_PRIVATE 0x2
-#define MAP_SHARED_VALIDATE 0x3
-// 0x4-0xf are unused.
-// These are the other flags, and zero or more of these can be set.
-#define MAP_FIXED 0x10
-#define MAP_ANONYMOUS 0x20
-#define MAP_ANON MAP_ANONYMOUS
-#define MAP_32BIT 0x40
-// 0x80 is unused.
-#define MAP_GROWSDOWN 0x100
-#define MAP_DENYWRITE 0x800
-#define MAP_EXECUTABLE 0x1000 // Compatibility flag. Ignored.
-#define MAP_LOCKED 0x2000
-#define MAP_NORESERVE 0x4000
-#define MAP_POPULATE 0x8000
-#define MAP_NONBLOCK 0x10000
-#define MAP_STACK 0x20000
-#define MAP_HUGETLB 0x40000
-#define MAP_SYNC 0x80000
-#define MAP_FIXED_NOREPLACE 0x100000
-// HUGETLB support macros. If ma_HUGHTLB is set, the bits under MAP_HUGE_MASK
-// represent the base-2 logarithm of the desired page size, and MAP_HUGE_2MB/1GB
-// are common sizes.
-#define MAP_HUGE_SHIFT 26
-#define MAP_HUGE_MASK 0x3f
-#define MAP_HUGE_2MB (21 << MAP_HUGE_SHIFT)
-#define MAP_HUGE_1GB (30 << MAP_HUGE_SHIFT)
-
-// Memory sync flags. (msync)
-#define MS_ASYNC 1
-#define MS_INVALIDATE 2
-#define MS_SYNC 4
-
-// Memory advice flags. (madvise)
-#define MADV_NORMAL 0
-#define MADV_RANDOM 1
-#define MADV_SEQUENTIAL 2
-#define MADV_WILLNEED 3
-#define MADV_DONTNEED 4
-#define MADV_FREE 8
-#define MADV_REMOVE 9
-#define MADV_DONTFORK 10
-#define MADV_DOFORK 11
-#define MADV_MERGEABLE 12
-#define MADV_UNMERGEABLE 13
-#define MADV_HUGEPAGE 14
-#define MADV_NOHUGEPAGE 15
-#define MADV_DONTDUMP 16
-#define MADV_DODUMP 17
-#define MADV_WIPEONFORK 18
-#define MADV_KEEPONFORK 19
-#define MADV_COLD 20
-#define MADV_PAGEOUT 21
-#define MADV_HWPOISON 100
-
 // Posix memory advise flags. (posix_madvise)
 #define POSIX_MADV_NORMAL MADV_NORMAL
 #define POSIX_MADV_SEQUENTIAL MADV_SEQUENTIAL
 #define POSIX_MADV_RANDOM MADV_RANDOM
 #define POSIX_MADV_WILLNEED MADV_WILLNEED
 #define POSIX_MADV_DONTNEED MADV_DONTNEED
-
 #endif // __LLVM_LIBC_MACROS_LINUX_SYS_MMAN_MACROS_H

``````````

</details>


https://github.com/llvm/llvm-project/pull/79652