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authorGuo Ren <ren_guo@c-sky.com>2018-09-05 14:25:12 +0800
committerGuo Ren <ren_guo@c-sky.com>2018-10-25 23:36:19 +0800
commit013de2d6671d89de3397904749c86a69ac0686f7 (patch)
treea957e4719ccb7f7383bfa17f8937d61409ee9119 /arch/csky/abiv1/mmap.c
parent00a9730e1007c6cc87a7c78af2f24a4105d616ee (diff)
downloadlinux-sh-013de2d6671d89de3397904749c86a69ac0686f7.tar.gz
csky: MMU and page table management
This patch adds files related to memory management and here is our memory-layout: Fixmap : 0xffc02000 – 0xfffff000 (4 MB - 12KB) Pkmap : 0xff800000 – 0xffc00000 (4 MB) Vmalloc : 0xf0200000 – 0xff000000 (238 MB) Lowmem : 0x80000000 – 0xc0000000 (1GB) abiv1 CPU (CK610) is VIPT cache and it doesn't support highmem. abiv2 CPUs are all PIPT cache and they could support highmem. Lowmem is directly mapped by msa0 & msa1 reg, and we needn't setup memory page table for it. Link:https://lore.kernel.org/lkml/20180518215548.GH17671@n2100.armlinux.org.uk/ Signed-off-by: Guo Ren <ren_guo@c-sky.com> Cc: Christoph Hellwig <hch@infradead.org> Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Diffstat (limited to 'arch/csky/abiv1/mmap.c')
-rw-r--r--arch/csky/abiv1/mmap.c66
1 files changed, 66 insertions, 0 deletions
diff --git a/arch/csky/abiv1/mmap.c b/arch/csky/abiv1/mmap.c
new file mode 100644
index 000000000000..b462fd50b23a
--- /dev/null
+++ b/arch/csky/abiv1/mmap.c
@@ -0,0 +1,66 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd.
+
+#include <linux/fs.h>
+#include <linux/mm.h>
+#include <linux/mman.h>
+#include <linux/shm.h>
+#include <linux/sched.h>
+#include <linux/random.h>
+#include <linux/io.h>
+
+unsigned long shm_align_mask = (0x4000 >> 1) - 1; /* Sane caches */
+
+#define COLOUR_ALIGN(addr, pgoff) \
+ ((((addr) + shm_align_mask) & ~shm_align_mask) + \
+ (((pgoff) << PAGE_SHIFT) & shm_align_mask))
+
+unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr,
+ unsigned long len, unsigned long pgoff, unsigned long flags)
+{
+ struct vm_area_struct *vmm;
+ int do_color_align;
+
+ if (flags & MAP_FIXED) {
+ /*
+ * We do not accept a shared mapping if it would violate
+ * cache aliasing constraints.
+ */
+ if ((flags & MAP_SHARED) &&
+ ((addr - (pgoff << PAGE_SHIFT)) & shm_align_mask))
+ return -EINVAL;
+ return addr;
+ }
+
+ if (len > TASK_SIZE)
+ return -ENOMEM;
+ do_color_align = 0;
+ if (filp || (flags & MAP_SHARED))
+ do_color_align = 1;
+ if (addr) {
+ if (do_color_align)
+ addr = COLOUR_ALIGN(addr, pgoff);
+ else
+ addr = PAGE_ALIGN(addr);
+ vmm = find_vma(current->mm, addr);
+ if (TASK_SIZE - len >= addr &&
+ (!vmm || addr + len <= vmm->vm_start))
+ return addr;
+ }
+ addr = TASK_UNMAPPED_BASE;
+ if (do_color_align)
+ addr = COLOUR_ALIGN(addr, pgoff);
+ else
+ addr = PAGE_ALIGN(addr);
+
+ for (vmm = find_vma(current->mm, addr); ; vmm = vmm->vm_next) {
+ /* At this point: (!vmm || addr < vmm->vm_end). */
+ if (TASK_SIZE - len < addr)
+ return -ENOMEM;
+ if (!vmm || addr + len <= vmm->vm_start)
+ return addr;
+ addr = vmm->vm_end;
+ if (do_color_align)
+ addr = COLOUR_ALIGN(addr, pgoff);
+ }
+}