static char *elfnotes_buf;
static size_t elfnotes_sz;
+/* Size of all notes minus the device dump notes */
+static size_t elfnotes_orig_sz;
/* Total size of vmcore file. */
static u64 vmcore_size;
static DEFINE_MUTEX(vmcoredd_mutex);
#endif /* CONFIG_PROC_VMCORE_DEVICE_DUMP */
+/* Device Dump Size */
+static size_t vmcoredd_orig_sz;
+
/*
* Returns > 0 for RAM pages, 0 for non-RAM pages, < 0 on error
* The called function has to take care of module refcounting.
return 0;
}
+#ifdef CONFIG_PROC_VMCORE_DEVICE_DUMP
+static int vmcoredd_copy_dumps(void *dst, u64 start, size_t size, int userbuf)
+{
+ struct vmcoredd_node *dump;
+ u64 offset = 0;
+ int ret = 0;
+ size_t tsz;
+ char *buf;
+
+ mutex_lock(&vmcoredd_mutex);
+ list_for_each_entry(dump, &vmcoredd_list, list) {
+ if (start < offset + dump->size) {
+ tsz = min(offset + (u64)dump->size - start, (u64)size);
+ buf = dump->buf + start - offset;
+ if (copy_to(dst, buf, tsz, userbuf)) {
+ ret = -EFAULT;
+ goto out_unlock;
+ }
+
+ size -= tsz;
+ start += tsz;
+ dst += tsz;
+
+ /* Leave now if buffer filled already */
+ if (!size)
+ goto out_unlock;
+ }
+ offset += dump->size;
+ }
+
+out_unlock:
+ mutex_unlock(&vmcoredd_mutex);
+ return ret;
+}
+
+static int vmcoredd_mmap_dumps(struct vm_area_struct *vma, unsigned long dst,
+ u64 start, size_t size)
+{
+ struct vmcoredd_node *dump;
+ u64 offset = 0;
+ int ret = 0;
+ size_t tsz;
+ char *buf;
+
+ mutex_lock(&vmcoredd_mutex);
+ list_for_each_entry(dump, &vmcoredd_list, list) {
+ if (start < offset + dump->size) {
+ tsz = min(offset + (u64)dump->size - start, (u64)size);
+ buf = dump->buf + start - offset;
+ if (remap_vmalloc_range_partial(vma, dst, buf, tsz)) {
+ ret = -EFAULT;
+ goto out_unlock;
+ }
+
+ size -= tsz;
+ start += tsz;
+ dst += tsz;
+
+ /* Leave now if buffer filled already */
+ if (!size)
+ goto out_unlock;
+ }
+ offset += dump->size;
+ }
+
+out_unlock:
+ mutex_unlock(&vmcoredd_mutex);
+ return ret;
+}
+#endif /* CONFIG_PROC_VMCORE_DEVICE_DUMP */
+
/* Read from the ELF header and then the crash dump. On error, negative value is
* returned otherwise number of bytes read are returned.
*/
if (*fpos < elfcorebuf_sz + elfnotes_sz) {
void *kaddr;
+ /* We add device dumps before other elf notes because the
+ * other elf notes may not fill the elf notes buffer
+ * completely and we will end up with zero-filled data
+ * between the elf notes and the device dumps. Tools will
+ * then try to decode this zero-filled data as valid notes
+ * and we don't want that. Hence, adding device dumps before
+ * the other elf notes ensure that zero-filled data can be
+ * avoided.
+ */
+#ifdef CONFIG_PROC_VMCORE_DEVICE_DUMP
+ /* Read device dumps */
+ if (*fpos < elfcorebuf_sz + vmcoredd_orig_sz) {
+ tsz = min(elfcorebuf_sz + vmcoredd_orig_sz -
+ (size_t)*fpos, buflen);
+ start = *fpos - elfcorebuf_sz;
+ if (vmcoredd_copy_dumps(buffer, start, tsz, userbuf))
+ return -EFAULT;
+
+ buflen -= tsz;
+ *fpos += tsz;
+ buffer += tsz;
+ acc += tsz;
+
+ /* leave now if filled buffer already */
+ if (!buflen)
+ return acc;
+ }
+#endif /* CONFIG_PROC_VMCORE_DEVICE_DUMP */
+
+ /* Read remaining elf notes */
tsz = min(elfcorebuf_sz + elfnotes_sz - (size_t)*fpos, buflen);
- kaddr = elfnotes_buf + *fpos - elfcorebuf_sz;
+ kaddr = elfnotes_buf + *fpos - elfcorebuf_sz - vmcoredd_orig_sz;
if (copy_to(buffer, kaddr, tsz, userbuf))
return -EFAULT;
+
buflen -= tsz;
*fpos += tsz;
buffer += tsz;
if (start < elfcorebuf_sz + elfnotes_sz) {
void *kaddr;
+ /* We add device dumps before other elf notes because the
+ * other elf notes may not fill the elf notes buffer
+ * completely and we will end up with zero-filled data
+ * between the elf notes and the device dumps. Tools will
+ * then try to decode this zero-filled data as valid notes
+ * and we don't want that. Hence, adding device dumps before
+ * the other elf notes ensure that zero-filled data can be
+ * avoided. This also ensures that the device dumps and
+ * other elf notes can be properly mmaped at page aligned
+ * address.
+ */
+#ifdef CONFIG_PROC_VMCORE_DEVICE_DUMP
+ /* Read device dumps */
+ if (start < elfcorebuf_sz + vmcoredd_orig_sz) {
+ u64 start_off;
+
+ tsz = min(elfcorebuf_sz + vmcoredd_orig_sz -
+ (size_t)start, size);
+ start_off = start - elfcorebuf_sz;
+ if (vmcoredd_mmap_dumps(vma, vma->vm_start + len,
+ start_off, tsz))
+ goto fail;
+
+ size -= tsz;
+ start += tsz;
+ len += tsz;
+
+ /* leave now if filled buffer already */
+ if (!size)
+ return 0;
+ }
+#endif /* CONFIG_PROC_VMCORE_DEVICE_DUMP */
+
+ /* Read remaining elf notes */
tsz = min(elfcorebuf_sz + elfnotes_sz - (size_t)start, size);
- kaddr = elfnotes_buf + start - elfcorebuf_sz;
+ kaddr = elfnotes_buf + start - elfcorebuf_sz - vmcoredd_orig_sz;
if (remap_vmalloc_range_partial(vma, vma->vm_start + len,
kaddr, tsz))
goto fail;
+
size -= tsz;
start += tsz;
len += tsz;
/* Modify e_phnum to reflect merged headers. */
ehdr_ptr->e_phnum = ehdr_ptr->e_phnum - nr_ptnote + 1;
+ /* Store the size of all notes. We need this to update the note
+ * header when the device dumps will be added.
+ */
+ elfnotes_orig_sz = phdr.p_memsz;
+
return 0;
}
/* Modify e_phnum to reflect merged headers. */
ehdr_ptr->e_phnum = ehdr_ptr->e_phnum - nr_ptnote + 1;
+ /* Store the size of all notes. We need this to update the note
+ * header when the device dumps will be added.
+ */
+ elfnotes_orig_sz = phdr.p_memsz;
+
return 0;
}
}
/* Sets offset fields of vmcore elements. */
-static void __init set_vmcore_list_offsets(size_t elfsz, size_t elfnotes_sz,
- struct list_head *vc_list)
+static void set_vmcore_list_offsets(size_t elfsz, size_t elfnotes_sz,
+ struct list_head *vc_list)
{
loff_t vmcore_off;
struct vmcore *m;
memcpy(vdd_hdr->dump_name, data->dump_name, sizeof(vdd_hdr->dump_name));
}
+/**
+ * vmcoredd_update_program_headers - Update all Elf program headers
+ * @elfptr: Pointer to elf header
+ * @elfnotesz: Size of elf notes aligned to page size
+ * @vmcoreddsz: Size of device dumps to be added to elf note header
+ *
+ * Determine type of Elf header (Elf64 or Elf32) and update the elf note size.
+ * Also update the offsets of all the program headers after the elf note header.
+ */
+static void vmcoredd_update_program_headers(char *elfptr, size_t elfnotesz,
+ size_t vmcoreddsz)
+{
+ unsigned char *e_ident = (unsigned char *)elfptr;
+ u64 start, end, size;
+ loff_t vmcore_off;
+ u32 i;
+
+ vmcore_off = elfcorebuf_sz + elfnotesz;
+
+ if (e_ident[EI_CLASS] == ELFCLASS64) {
+ Elf64_Ehdr *ehdr = (Elf64_Ehdr *)elfptr;
+ Elf64_Phdr *phdr = (Elf64_Phdr *)(elfptr + sizeof(Elf64_Ehdr));
+
+ /* Update all program headers */
+ for (i = 0; i < ehdr->e_phnum; i++, phdr++) {
+ if (phdr->p_type == PT_NOTE) {
+ /* Update note size */
+ phdr->p_memsz = elfnotes_orig_sz + vmcoreddsz;
+ phdr->p_filesz = phdr->p_memsz;
+ continue;
+ }
+
+ start = rounddown(phdr->p_offset, PAGE_SIZE);
+ end = roundup(phdr->p_offset + phdr->p_memsz,
+ PAGE_SIZE);
+ size = end - start;
+ phdr->p_offset = vmcore_off + (phdr->p_offset - start);
+ vmcore_off += size;
+ }
+ } else {
+ Elf32_Ehdr *ehdr = (Elf32_Ehdr *)elfptr;
+ Elf32_Phdr *phdr = (Elf32_Phdr *)(elfptr + sizeof(Elf32_Ehdr));
+
+ /* Update all program headers */
+ for (i = 0; i < ehdr->e_phnum; i++, phdr++) {
+ if (phdr->p_type == PT_NOTE) {
+ /* Update note size */
+ phdr->p_memsz = elfnotes_orig_sz + vmcoreddsz;
+ phdr->p_filesz = phdr->p_memsz;
+ continue;
+ }
+
+ start = rounddown(phdr->p_offset, PAGE_SIZE);
+ end = roundup(phdr->p_offset + phdr->p_memsz,
+ PAGE_SIZE);
+ size = end - start;
+ phdr->p_offset = vmcore_off + (phdr->p_offset - start);
+ vmcore_off += size;
+ }
+ }
+}
+
+/**
+ * vmcoredd_update_size - Update the total size of the device dumps and update
+ * Elf header
+ * @dump_size: Size of the current device dump to be added to total size
+ *
+ * Update the total size of all the device dumps and update the Elf program
+ * headers. Calculate the new offsets for the vmcore list and update the
+ * total vmcore size.
+ */
+static void vmcoredd_update_size(size_t dump_size)
+{
+ vmcoredd_orig_sz += dump_size;
+ elfnotes_sz = roundup(elfnotes_orig_sz, PAGE_SIZE) + vmcoredd_orig_sz;
+ vmcoredd_update_program_headers(elfcorebuf, elfnotes_sz,
+ vmcoredd_orig_sz);
+
+ /* Update vmcore list offsets */
+ set_vmcore_list_offsets(elfcorebuf_sz, elfnotes_sz, &vmcore_list);
+
+ vmcore_size = get_vmcore_size(elfcorebuf_sz, elfnotes_sz,
+ &vmcore_list);
+ proc_vmcore->size = vmcore_size;
+}
+
/**
* vmcore_add_device_dump - Add a buffer containing device dump to vmcore
* @data: dump info.
list_add_tail(&dump->list, &vmcoredd_list);
mutex_unlock(&vmcoredd_mutex);
+ vmcoredd_update_size(data_size);
return 0;
out_err:
projects / users / hch / xfs.git / commitdiff