Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261650AbVASH5e (ORCPT ); Wed, 19 Jan 2005 02:57:34 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261649AbVASHzu (ORCPT ); Wed, 19 Jan 2005 02:55:50 -0500 Received: from ebiederm.dsl.xmission.com ([166.70.28.69]:52159 "EHLO ebiederm.dsl.xmission.com") by vger.kernel.org with ESMTP id S261630AbVASHdX (ORCPT ); Wed, 19 Jan 2005 02:33:23 -0500 From: "Eric W. Biederman" To: Andrew Morton Cc: , Subject: [PATCH 27/29] crashdump-routines-for-copying-dump-pages Date: Wed, 19 Jan 2005 0:31:37 -0700 Message-ID: X-Mailer: patch-bomb.pl@ebiederm.dsl.xmission.com In-Reply-To: References: Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4737 Lines: 117 kernel/crash.c has been renamed kernel/crash_dump.c to clarify it's purpose. From: Hariprasad Nellitheertha This patch provides the interfaces necessary to read the dump contents, treating it as a high memory device. Signed off by Hariprasad Nellitheertha Signed-off-by: Eric Biederman --- arch/i386/mm/highmem.c | 18 ++++++++++++++++++ include/asm-i386/highmem.h | 1 + include/linux/highmem.h | 1 + kernel/crash_dump.c | 33 +++++++++++++++++++++++++++++++++ 4 files changed, 53 insertions(+) diff -uNr linux-2.6.11-rc1-mm1-nokexec-crashdump-memory-preserving-reboot-using-kexec/arch/i386/mm/highmem.c linux-2.6.11-rc1-mm1-nokexec-crashdump-routines-for-copying-dump-pages/arch/i386/mm/highmem.c --- linux-2.6.11-rc1-mm1-nokexec-crashdump-memory-preserving-reboot-using-kexec/arch/i386/mm/highmem.c Fri Jan 14 04:32:22 2005 +++ linux-2.6.11-rc1-mm1-nokexec-crashdump-routines-for-copying-dump-pages/arch/i386/mm/highmem.c Tue Jan 18 23:16:41 2005 @@ -74,6 +74,24 @@ preempt_check_resched(); } +/* This is the same as kmap_atomic() but can map memory that doesn't + * have a struct page associated with it. + */ +void *kmap_atomic_pfn(unsigned long pfn, enum km_type type) +{ + enum fixed_addresses idx; + unsigned long vaddr; + + inc_preempt_count(); + + idx = type + KM_TYPE_NR*smp_processor_id(); + vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx); + set_pte(kmap_pte-idx, pfn_pte(pfn, kmap_prot)); + __flush_tlb_one(vaddr); + + return (void*) vaddr; +} + struct page *kmap_atomic_to_page(char *ptr) { unsigned long idx, vaddr = (unsigned long)ptr; diff -uNr linux-2.6.11-rc1-mm1-nokexec-crashdump-memory-preserving-reboot-using-kexec/include/asm-i386/highmem.h linux-2.6.11-rc1-mm1-nokexec-crashdump-routines-for-copying-dump-pages/include/asm-i386/highmem.h --- linux-2.6.11-rc1-mm1-nokexec-crashdump-memory-preserving-reboot-using-kexec/include/asm-i386/highmem.h Fri Jan 14 04:32:27 2005 +++ linux-2.6.11-rc1-mm1-nokexec-crashdump-routines-for-copying-dump-pages/include/asm-i386/highmem.h Tue Jan 18 23:16:41 2005 @@ -72,6 +72,7 @@ void kunmap(struct page *page); char *kmap_atomic(struct page *page, enum km_type type); void kunmap_atomic(char *kvaddr, enum km_type type); +void *kmap_atomic_pfn(unsigned long pfn, enum km_type type); struct page *kmap_atomic_to_page(char *ptr); #define flush_cache_kmaps() do { } while (0) diff -uNr linux-2.6.11-rc1-mm1-nokexec-crashdump-memory-preserving-reboot-using-kexec/include/linux/highmem.h linux-2.6.11-rc1-mm1-nokexec-crashdump-routines-for-copying-dump-pages/include/linux/highmem.h --- linux-2.6.11-rc1-mm1-nokexec-crashdump-memory-preserving-reboot-using-kexec/include/linux/highmem.h Fri Jan 14 04:32:27 2005 +++ linux-2.6.11-rc1-mm1-nokexec-crashdump-routines-for-copying-dump-pages/include/linux/highmem.h Tue Jan 18 23:16:41 2005 @@ -28,6 +28,7 @@ #define kmap_atomic(page, idx) ((char *)page_address(page)) #define kunmap_atomic(addr, idx) do { char *p = addr; (void)p; } while (0) +#define kmap_atomic_pfn(pfn, idx) page_address(pfn_to_page(pfn)) #define kmap_atomic_to_page(ptr) virt_to_page(ptr) #endif /* CONFIG_HIGHMEM */ diff -uNr linux-2.6.11-rc1-mm1-nokexec-crashdump-memory-preserving-reboot-using-kexec/kernel/crash_dump.c linux-2.6.11-rc1-mm1-nokexec-crashdump-routines-for-copying-dump-pages/kernel/crash_dump.c --- linux-2.6.11-rc1-mm1-nokexec-crashdump-memory-preserving-reboot-using-kexec/kernel/crash_dump.c Tue Jan 18 23:16:24 2005 +++ linux-2.6.11-rc1-mm1-nokexec-crashdump-routines-for-copying-dump-pages/kernel/crash_dump.c Tue Jan 18 23:16:41 2005 @@ -8,6 +8,39 @@ #include #include #include +#include +#include +#include + #include #include +/* + * Copy a page from "oldmem". For this page, there is no pte mapped + * in the current kernel. We stitch up a pte, similar to kmap_atomic. + */ +ssize_t copy_oldmem_page(unsigned long pfn, char *buf, + size_t csize, int userbuf) +{ + void *page, *vaddr; + + if (!csize) + return 0; + + page = kmalloc(PAGE_SIZE, GFP_KERNEL); + + vaddr = kmap_atomic_pfn(pfn, KM_PTE0); + copy_page(page, vaddr); + kunmap_atomic(vaddr, KM_PTE0); + + if (userbuf) { + if (copy_to_user(buf, page, csize)) { + kfree(page); + return -EFAULT; + } + } else + memcpy(buf, page, csize); + kfree(page); + + return 0; +} - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/