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authorSven Schnelle <svens@stackframe.org>2019-04-04 21:14:08 +0200
committerHelge Deller <deller@gmx.de>2019-05-03 23:47:38 +0200
commitccfbc68d41c2db8f5e88128427fb5bfe3855ff9b (patch)
tree836e66257a79c236cfc6b3a1a6d1f6e377102c40 /arch/parisc
parent17d9822d4b4c1bfeb14971d9a2639698e7f5b1eb (diff)
downloadlinux-ccfbc68d41c2db8f5e88128427fb5bfe3855ff9b.tar.bz2
parisc: add set_fixmap()/clear_fixmap()
These functions will be used for adding code patching functions later. Signed-off-by: Sven Schnelle <svens@stackframe.org> Signed-off-by: Helge Deller <deller@gmx.de>
Diffstat (limited to 'arch/parisc')
-rw-r--r--arch/parisc/include/asm/fixmap.h19
-rw-r--r--arch/parisc/mm/Makefile2
-rw-r--r--arch/parisc/mm/fixmap.c41
-rw-r--r--arch/parisc/mm/init.c14
4 files changed, 69 insertions, 7 deletions
diff --git a/arch/parisc/include/asm/fixmap.h b/arch/parisc/include/asm/fixmap.h
index f7c3a0905de4..288da73d4cc0 100644
--- a/arch/parisc/include/asm/fixmap.h
+++ b/arch/parisc/include/asm/fixmap.h
@@ -15,17 +15,34 @@
* from areas congruently mapped with user space. It is 8MB large
* and must be 16MB aligned */
#define TMPALIAS_MAP_START ((__PAGE_OFFSET) - 16*1024*1024)
+
+#define FIXMAP_SIZE (FIX_BITMAP_COUNT << PAGE_SHIFT)
+#define FIXMAP_START (TMPALIAS_MAP_START - FIXMAP_SIZE)
/* This is the kernel area for all maps (vmalloc, dma etc.) most
* usually, it extends up to TMPALIAS_MAP_START. Virtual addresses
* 0..GATEWAY_PAGE_SIZE are reserved for the gateway page */
#define KERNEL_MAP_START (GATEWAY_PAGE_SIZE)
-#define KERNEL_MAP_END (TMPALIAS_MAP_START)
+#define KERNEL_MAP_END (FIXMAP_START)
#ifndef __ASSEMBLY__
+
+
+enum fixed_addresses {
+ /* Support writing RO kernel text via kprobes, jump labels, etc. */
+ FIX_TEXT_POKE0,
+ FIX_BITMAP_COUNT
+};
+
extern void *parisc_vmalloc_start;
#define PCXL_DMA_MAP_SIZE (8*1024*1024)
#define VMALLOC_START ((unsigned long)parisc_vmalloc_start)
#define VMALLOC_END (KERNEL_MAP_END)
+
+#define __fix_to_virt(_x) (FIXMAP_START + ((_x) << PAGE_SHIFT))
+
+void set_fixmap(enum fixed_addresses idx, phys_addr_t phys);
+void clear_fixmap(enum fixed_addresses idx);
+
#endif /*__ASSEMBLY__*/
#endif /*_ASM_FIXMAP_H*/
diff --git a/arch/parisc/mm/Makefile b/arch/parisc/mm/Makefile
index 134393de69d2..20e39b043a60 100644
--- a/arch/parisc/mm/Makefile
+++ b/arch/parisc/mm/Makefile
@@ -2,5 +2,5 @@
# Makefile for arch/parisc/mm
#
-obj-y := init.o fault.o ioremap.o
+obj-y := init.o fault.o ioremap.o fixmap.o
obj-$(CONFIG_HUGETLB_PAGE) += hugetlbpage.o
diff --git a/arch/parisc/mm/fixmap.c b/arch/parisc/mm/fixmap.c
new file mode 100644
index 000000000000..c8d41b54fb19
--- /dev/null
+++ b/arch/parisc/mm/fixmap.c
@@ -0,0 +1,41 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * fixmaps for parisc
+ *
+ * Copyright (c) 2019 Sven Schnelle <svens@stackframe.org>
+ */
+
+#include <linux/kprobes.h>
+#include <linux/mm.h>
+#include <asm/cacheflush.h>
+#include <asm/fixmap.h>
+
+void set_fixmap(enum fixed_addresses idx, phys_addr_t phys)
+{
+ unsigned long vaddr = __fix_to_virt(idx);
+ pgd_t *pgd = pgd_offset_k(vaddr);
+ pmd_t *pmd = pmd_offset(pgd, vaddr);
+ pte_t *pte;
+
+ if (pmd_none(*pmd))
+ pmd = pmd_alloc(NULL, pgd, vaddr);
+
+ pte = pte_offset_kernel(pmd, vaddr);
+ if (pte_none(*pte))
+ pte = pte_alloc_kernel(pmd, vaddr);
+
+ set_pte_at(&init_mm, vaddr, pte, __mk_pte(phys, PAGE_KERNEL_RWX));
+ flush_tlb_kernel_range(vaddr, vaddr + PAGE_SIZE);
+}
+
+void clear_fixmap(enum fixed_addresses idx)
+{
+ unsigned long vaddr = __fix_to_virt(idx);
+ pgd_t *pgd = pgd_offset_k(vaddr);
+ pmd_t *pmd = pmd_offset(pgd, vaddr);
+ pte_t *pte = pte_offset_kernel(pmd, vaddr);
+
+ pte_clear(&init_mm, vaddr, pte);
+
+ flush_tlb_kernel_range(vaddr, vaddr + PAGE_SIZE);
+}
diff --git a/arch/parisc/mm/init.c b/arch/parisc/mm/init.c
index d0b166256f1a..b2b52de2b82b 100644
--- a/arch/parisc/mm/init.c
+++ b/arch/parisc/mm/init.c
@@ -622,15 +622,19 @@ void __init mem_init(void)
* But keep code for debugging purposes.
*/
printk("virtual kernel memory layout:\n"
- " vmalloc : 0x%px - 0x%px (%4ld MB)\n"
- " memory : 0x%px - 0x%px (%4ld MB)\n"
- " .init : 0x%px - 0x%px (%4ld kB)\n"
- " .data : 0x%px - 0x%px (%4ld kB)\n"
- " .text : 0x%px - 0x%px (%4ld kB)\n",
+ " vmalloc : 0x%px - 0x%px (%4ld MB)\n"
+ " fixmap : 0x%px - 0x%px (%4ld kB)\n"
+ " memory : 0x%px - 0x%px (%4ld MB)\n"
+ " .init : 0x%px - 0x%px (%4ld kB)\n"
+ " .data : 0x%px - 0x%px (%4ld kB)\n"
+ " .text : 0x%px - 0x%px (%4ld kB)\n",
(void*)VMALLOC_START, (void*)VMALLOC_END,
(VMALLOC_END - VMALLOC_START) >> 20,
+ (void *)FIXMAP_START, (void *)(FIXMAP_START + FIXMAP_SIZE),
+ (unsigned long)(FIXMAP_SIZE / 1024),
+
__va(0), high_memory,
((unsigned long)high_memory - (unsigned long)__va(0)) >> 20,