The patch titled Subject: vmcore: introduce mmap_vmcore() has been removed from the -mm tree. Its filename was vmcore-introduce-mmap_vmcore.patch This patch was dropped because it was nacked ------------------------------------------------------ From: HATAYAMA Daisuke <d.hatayama@xxxxxxxxxxxxxx> Subject: vmcore: introduce mmap_vmcore() This patch introduces mmap_vmcore(). If flag MEM_TYPE_CURRENT_KERNEL is set, remapped is the buffer on the 2nd kernel. If not set, remapped is some area in old memory. Neither writable nor executable mapping is permitted even with mprotect(). Non-writable mapping is also requirement of remap_pfn_range() when mapping linear pages on non-consequtive physical pages; see is_cow_mapping(). On x86-32 PAE kernels, mmap() supports at most 16TB memory only. This limitation comes from the fact that the third argument of remap_pfn_range(), pfn, is of 32-bit length on x86-32: unsigned long. Signed-off-by: HATAYAMA Daisuke <d.hatayama@xxxxxxxxxxxxxx> Cc: Zhang Yanfei <zhangyanfei@xxxxxxxxxxxxxx> Cc: Vivek Goyal <vgoyal@xxxxxxxxxx> Cc: "Eric W. Biederman" <ebiederm@xxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- fs/proc/vmcore.c | 72 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 72 insertions(+) diff -puN fs/proc/vmcore.c~vmcore-introduce-mmap_vmcore fs/proc/vmcore.c --- a/fs/proc/vmcore.c~vmcore-introduce-mmap_vmcore +++ a/fs/proc/vmcore.c @@ -185,9 +185,81 @@ static ssize_t read_vmcore(struct file * return acc; } +static int mmap_vmcore(struct file *file, struct vm_area_struct *vma) +{ + size_t size = vma->vm_end - vma->vm_start; + u64 start, end, len, tsz; + struct vmcore *m; + + if (!support_mmap_vmcore) + return -ENODEV; + + start = (u64)vma->vm_pgoff << PAGE_SHIFT; + end = start + size; + + if (size > vmcore_size || end > vmcore_size) + return -EINVAL; + + if (vma->vm_flags & (VM_WRITE | VM_EXEC)) + return -EPERM; + + vma->vm_flags &= ~(VM_MAYWRITE | VM_MAYEXEC); + + len = 0; + + if (start < elfcorebuf_sz) { + u64 pfn; + + tsz = elfcorebuf_sz - start; + if (size < tsz) + tsz = size; + pfn = __pa(elfcorebuf + start) >> PAGE_SHIFT; + if (remap_pfn_range(vma, vma->vm_start, pfn, tsz, + vma->vm_page_prot)) + return -EAGAIN; + size -= tsz; + start += tsz; + len += tsz; + + if (size == 0) + return 0; + } + + list_for_each_entry(m, &vmcore_list, list) { + if (start < m->offset + m->size) { + u64 pfn = 0; + + tsz = m->offset + m->size - start; + if (size < tsz) + tsz = size; + if (m->flag & MEM_TYPE_CURRENT_KERNEL) { + pfn = __pa(m->buf + start - m->offset) + >> PAGE_SHIFT; + } else { + pfn = (m->paddr + (start - m->offset)) + >> PAGE_SHIFT; + } + if (remap_pfn_range(vma, vma->vm_start + len, pfn, tsz, + vma->vm_page_prot)) { + do_munmap(vma->vm_mm, vma->vm_start, len); + return -EAGAIN; + } + size -= tsz; + start += tsz; + len += tsz; + + if (size == 0) + return 0; + } + } + + return 0; +} + static const struct file_operations proc_vmcore_operations = { .read = read_vmcore, .llseek = default_llseek, + .mmap = mmap_vmcore, }; static struct vmcore* __init get_new_element(void) _ Patches currently in -mm which might be from d.hatayama@xxxxxxxxxxxxxx are -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html