Previous commit introduced writing support for vmcore, it requires per-architecture implementation for the writing function.
Signed-off-by: Kairui Song <[email protected]> --- arch/x86/kernel/crash_dump_64.c | 49 +++++++++++++++++++++++++++------ 1 file changed, 40 insertions(+), 9 deletions(-) diff --git a/arch/x86/kernel/crash_dump_64.c b/arch/x86/kernel/crash_dump_64.c index 045e82e8945b..ec80da75b287 100644 --- a/arch/x86/kernel/crash_dump_64.c +++ b/arch/x86/kernel/crash_dump_64.c @@ -13,7 +13,7 @@ static ssize_t __copy_oldmem_page(unsigned long pfn, char *buf, size_t csize, unsigned long offset, int userbuf, - bool encrypted) + bool encrypted, bool is_write) { void *vaddr; @@ -28,13 +28,25 @@ static ssize_t __copy_oldmem_page(unsigned long pfn, char *buf, size_t csize, if (!vaddr) return -ENOMEM; - if (userbuf) { - if (copy_to_user((void __user *)buf, vaddr + offset, csize)) { - iounmap((void __iomem *)vaddr); - return -EFAULT; + if (is_write) { + if (userbuf) { + if (copy_from_user(vaddr + offset, (void __user *)buf, csize)) { + iounmap((void __iomem *)vaddr); + return -EFAULT; + } + } else { + memcpy(vaddr + offset, buf, csize); } - } else - memcpy(buf, vaddr + offset, csize); + } else { + if (userbuf) { + if (copy_to_user((void __user *)buf, vaddr + offset, csize)) { + iounmap((void __iomem *)vaddr); + return -EFAULT; + } + } else { + memcpy(buf, vaddr + offset, csize); + } + } set_iounmap_nonlazy(); iounmap((void __iomem *)vaddr); @@ -57,7 +69,7 @@ static ssize_t __copy_oldmem_page(unsigned long pfn, char *buf, size_t csize, ssize_t copy_oldmem_page(unsigned long pfn, char *buf, size_t csize, unsigned long offset, int userbuf) { - return __copy_oldmem_page(pfn, buf, csize, offset, userbuf, false); + return __copy_oldmem_page(pfn, buf, csize, offset, userbuf, false, false); } /** @@ -68,7 +80,26 @@ ssize_t copy_oldmem_page(unsigned long pfn, char *buf, size_t csize, ssize_t copy_oldmem_page_encrypted(unsigned long pfn, char *buf, size_t csize, unsigned long offset, int userbuf) { - return __copy_oldmem_page(pfn, buf, csize, offset, userbuf, true); + return __copy_oldmem_page(pfn, buf, csize, offset, userbuf, true, false); +} + +/** + * copy_to_oldmem_page - similar to copy_oldmem_page but in opposite direction. + */ +ssize_t copy_to_oldmem_page(unsigned long pfn, char *src, size_t csize, + unsigned long offset, int userbuf) +{ + return __copy_oldmem_page(pfn, src, csize, offset, userbuf, false, true); +} + +/** + * copy_to_oldmem_page_encrypted - similar to copy_oldmem_page_encrypted but + * in opposite direction. + */ +ssize_t copy_to_oldmem_page_encrypted(unsigned long pfn, char *src, size_t csize, + unsigned long offset, int userbuf) +{ + return __copy_oldmem_page(pfn, src, csize, offset, userbuf, true, true); } ssize_t elfcorehdr_read(char *buf, size_t count, u64 *ppos) -- 2.26.2
