diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2010-08-08 13:10:11 -0400 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2010-08-08 13:10:11 -0400 |
commit | 45d7f32c7a43cbb9592886d38190e379e2eb2226 (patch) | |
tree | ea68b67b1d2127527d856248c0485f2ed7e50088 /arch/tile/mm/mmap.c | |
parent | 53bcef60633086ad73683d01a4ef9ca678484d2d (diff) | |
parent | ab11b487402f97975f3ac1eeea09c82f4431481e (diff) |
Merge git://git.kernel.org/pub/scm/linux/kernel/git/cmetcalf/linux-tile
* git://git.kernel.org/pub/scm/linux/kernel/git/cmetcalf/linux-tile:
arch/tile: check kmalloc() result
arch/tile: catch up on various minor cleanups.
arch/tile: avoid erroneous error return for PTRACE_POKEUSR.
tile: set ARCH_KMALLOC_MINALIGN
tile: remove homegrown L1_CACHE_ALIGN macro
arch/tile: Miscellaneous cleanup changes.
arch/tile: Split the icache flush code off to a generic <arch> header.
arch/tile: Fix bug in support for atomic64_xx() ops.
arch/tile: Shrink the tile-opcode files considerably.
arch/tile: Add driver to enable access to the user dynamic network.
arch/tile: Enable more sophisticated IRQ model for 32-bit chips.
Move list types from <linux/list.h> to <linux/types.h>.
Add wait4() back to the set of <asm-generic/unistd.h> syscalls.
Revert adding some arch-specific signal syscalls to <linux/syscalls.h>.
arch/tile: Do not use GFP_KERNEL for dma_alloc_coherent(). Feedback from fujita.tomonori@lab.ntt.co.jp.
arch/tile: core support for Tilera 32-bit chips.
Fix up the "generic" unistd.h ABI to be more useful.
Diffstat (limited to 'arch/tile/mm/mmap.c')
-rw-r--r-- | arch/tile/mm/mmap.c | 75 |
1 files changed, 75 insertions, 0 deletions
diff --git a/arch/tile/mm/mmap.c b/arch/tile/mm/mmap.c new file mode 100644 index 000000000000..f96f4cec602a --- /dev/null +++ b/arch/tile/mm/mmap.c | |||
@@ -0,0 +1,75 @@ | |||
1 | /* | ||
2 | * Copyright 2010 Tilera Corporation. All Rights Reserved. | ||
3 | * | ||
4 | * This program is free software; you can redistribute it and/or | ||
5 | * modify it under the terms of the GNU General Public License | ||
6 | * as published by the Free Software Foundation, version 2. | ||
7 | * | ||
8 | * This program is distributed in the hope that it will be useful, but | ||
9 | * WITHOUT ANY WARRANTY; without even the implied warranty of | ||
10 | * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or | ||
11 | * NON INFRINGEMENT. See the GNU General Public License for | ||
12 | * more details. | ||
13 | * | ||
14 | * Taken from the i386 architecture and simplified. | ||
15 | */ | ||
16 | |||
17 | #include <linux/mm.h> | ||
18 | #include <linux/random.h> | ||
19 | #include <linux/limits.h> | ||
20 | #include <linux/sched.h> | ||
21 | #include <linux/mman.h> | ||
22 | #include <linux/compat.h> | ||
23 | |||
24 | /* | ||
25 | * Top of mmap area (just below the process stack). | ||
26 | * | ||
27 | * Leave an at least ~128 MB hole. | ||
28 | */ | ||
29 | #define MIN_GAP (128*1024*1024) | ||
30 | #define MAX_GAP (TASK_SIZE/6*5) | ||
31 | |||
32 | static inline unsigned long mmap_base(struct mm_struct *mm) | ||
33 | { | ||
34 | unsigned long gap = rlimit(RLIMIT_STACK); | ||
35 | unsigned long random_factor = 0; | ||
36 | |||
37 | if (current->flags & PF_RANDOMIZE) | ||
38 | random_factor = get_random_int() % (1024*1024); | ||
39 | |||
40 | if (gap < MIN_GAP) | ||
41 | gap = MIN_GAP; | ||
42 | else if (gap > MAX_GAP) | ||
43 | gap = MAX_GAP; | ||
44 | |||
45 | return PAGE_ALIGN(TASK_SIZE - gap - random_factor); | ||
46 | } | ||
47 | |||
48 | /* | ||
49 | * This function, called very early during the creation of a new | ||
50 | * process VM image, sets up which VM layout function to use: | ||
51 | */ | ||
52 | void arch_pick_mmap_layout(struct mm_struct *mm) | ||
53 | { | ||
54 | #if !defined(__tilegx__) | ||
55 | int is_32bit = 1; | ||
56 | #elif defined(CONFIG_COMPAT) | ||
57 | int is_32bit = is_compat_task(); | ||
58 | #else | ||
59 | int is_32bit = 0; | ||
60 | #endif | ||
61 | |||
62 | /* | ||
63 | * Use standard layout if the expected stack growth is unlimited | ||
64 | * or we are running native 64 bits. | ||
65 | */ | ||
66 | if (!is_32bit || rlimit(RLIMIT_STACK) == RLIM_INFINITY) { | ||
67 | mm->mmap_base = TASK_UNMAPPED_BASE; | ||
68 | mm->get_unmapped_area = arch_get_unmapped_area; | ||
69 | mm->unmap_area = arch_unmap_area; | ||
70 | } else { | ||
71 | mm->mmap_base = mmap_base(mm); | ||
72 | mm->get_unmapped_area = arch_get_unmapped_area_topdown; | ||
73 | mm->unmap_area = arch_unmap_area_topdown; | ||
74 | } | ||
75 | } | ||