diff options
Diffstat (limited to 'arch/powerpc/kernel/crash_dump.c')
-rw-r--r-- | arch/powerpc/kernel/crash_dump.c | 38 |
1 files changed, 27 insertions, 11 deletions
diff --git a/arch/powerpc/kernel/crash_dump.c b/arch/powerpc/kernel/crash_dump.c index 9ee3c5278db0..a323c9b32ee1 100644 --- a/arch/powerpc/kernel/crash_dump.c +++ b/arch/powerpc/kernel/crash_dump.c @@ -14,6 +14,7 @@ #include <linux/crash_dump.h> #include <linux/bootmem.h> #include <linux/lmb.h> +#include <asm/code-patching.h> #include <asm/kdump.h> #include <asm/prom.h> #include <asm/firmware.h> @@ -33,6 +34,8 @@ void __init reserve_kdump_trampoline(void) static void __init create_trampoline(unsigned long addr) { + unsigned int *p = (unsigned int *)addr; + /* The maximum range of a single instruction branch, is the current * instruction's address + (32 MB - 4) bytes. For the trampoline we * need to branch to current address + 32 MB. So we insert a nop at @@ -41,8 +44,8 @@ static void __init create_trampoline(unsigned long addr) * branch to "addr" we jump to ("addr" + 32 MB). Although it requires * two instructions it doesn't require any registers. */ - create_instruction(addr, 0x60000000); /* nop */ - create_branch(addr + 4, addr + PHYSICAL_START, 0); + patch_instruction(p, PPC_NOP_INSTR); + patch_branch(++p, addr + PHYSICAL_START, 0); } void __init setup_kdump_trampoline(void) @@ -83,6 +86,19 @@ static int __init parse_savemaxmem(char *p) } __setup("savemaxmem=", parse_savemaxmem); + +static size_t copy_oldmem_vaddr(void *vaddr, char *buf, size_t csize, + unsigned long offset, int userbuf) +{ + if (userbuf) { + if (copy_to_user((char __user *)buf, (vaddr + offset), csize)) + return -EFAULT; + } else + memcpy(buf, (vaddr + offset), csize); + + return csize; +} + /** * copy_oldmem_page - copy one page from "oldmem" * @pfn: page frame number to be copied @@ -104,16 +120,16 @@ ssize_t copy_oldmem_page(unsigned long pfn, char *buf, if (!csize) return 0; - vaddr = __ioremap(pfn << PAGE_SHIFT, PAGE_SIZE, 0); + csize = min(csize, PAGE_SIZE); - if (userbuf) { - if (copy_to_user((char __user *)buf, (vaddr + offset), csize)) { - iounmap(vaddr); - return -EFAULT; - } - } else - memcpy(buf, (vaddr + offset), csize); + if (pfn < max_pfn) { + vaddr = __va(pfn << PAGE_SHIFT); + csize = copy_oldmem_vaddr(vaddr, buf, csize, offset, userbuf); + } else { + vaddr = __ioremap(pfn << PAGE_SHIFT, PAGE_SIZE, 0); + csize = copy_oldmem_vaddr(vaddr, buf, csize, offset, userbuf); + iounmap(vaddr); + } - iounmap(vaddr); return csize; } |