+ __start_unwind, __end_unwind - __start_unwind,
+ __start_unwind_hdr, __end_unwind_hdr - __start_unwind_hdr);
+}
+
+static const u32 bad_cie, not_fde;
+static const u32 *cie_for_fde(const u32 *fde, const struct unwind_table *);
+static signed fde_pointer_type(const u32 *cie);
+
+struct eh_frame_hdr_table_entry {
+ unsigned long start, fde;
+};
+
+static int cmp_eh_frame_hdr_table_entries(const void *p1, const void *p2)
+{
+ const struct eh_frame_hdr_table_entry *e1 = p1;
+ const struct eh_frame_hdr_table_entry *e2 = p2;
+
+ return (e1->start > e2->start) - (e1->start < e2->start);
+}
+
+static void swap_eh_frame_hdr_table_entries(void *p1, void *p2, int size)
+{
+ struct eh_frame_hdr_table_entry *e1 = p1;
+ struct eh_frame_hdr_table_entry *e2 = p2;
+ unsigned long v;
+
+ v = e1->start;
+ e1->start = e2->start;
+ e2->start = v;
+ v = e1->fde;
+ e1->fde = e2->fde;
+ e2->fde = v;
+}
+
+static void __init setup_unwind_table(struct unwind_table *table,
+ void *(*alloc)(unsigned long))
+{
+ const u8 *ptr;
+ unsigned long tableSize = table->size, hdrSize;
+ unsigned n;
+ const u32 *fde;
+ struct {
+ u8 version;
+ u8 eh_frame_ptr_enc;
+ u8 fde_count_enc;
+ u8 table_enc;
+ unsigned long eh_frame_ptr;
+ unsigned int fde_count;
+ struct eh_frame_hdr_table_entry table[];
+ } __attribute__((__packed__)) *header;
+
+ if (table->header)
+ return;
+
+ if (table->hdrsz)
+ printk(KERN_WARNING ".eh_frame_hdr for '%s' present but unusable\n",
+ table->name);
+
+ if (tableSize & (sizeof(*fde) - 1))
+ return;
+
+ for (fde = table->address, n = 0;
+ tableSize > sizeof(*fde) && tableSize - sizeof(*fde) >= *fde;
+ tableSize -= sizeof(*fde) + *fde, fde += 1 + *fde / sizeof(*fde)) {
+ const u32 *cie = cie_for_fde(fde, table);
+ signed ptrType;
+
+ if (cie == ¬_fde)
+ continue;
+ if (cie == NULL
+ || cie == &bad_cie
+ || (ptrType = fde_pointer_type(cie)) < 0)
+ return;
+ ptr = (const u8 *)(fde + 2);
+ if (!read_pointer(&ptr,
+ (const u8 *)(fde + 1) + *fde,
+ ptrType))
+ return;
+ ++n;
+ }
+
+ if (tableSize || !n)
+ return;
+
+ hdrSize = 4 + sizeof(unsigned long) + sizeof(unsigned int)
+ + 2 * n * sizeof(unsigned long);
+ header = alloc(hdrSize);
+ if (!header)
+ return;
+ header->version = 1;
+ header->eh_frame_ptr_enc = DW_EH_PE_abs|DW_EH_PE_native;
+ header->fde_count_enc = DW_EH_PE_abs|DW_EH_PE_data4;
+ header->table_enc = DW_EH_PE_abs|DW_EH_PE_native;
+ put_unaligned((unsigned long)table->address, &header->eh_frame_ptr);
+ BUILD_BUG_ON(offsetof(typeof(*header), fde_count)
+ % __alignof(typeof(header->fde_count)));
+ header->fde_count = n;
+
+ BUILD_BUG_ON(offsetof(typeof(*header), table)
+ % __alignof(typeof(*header->table)));
+ for (fde = table->address, tableSize = table->size, n = 0;
+ tableSize;
+ tableSize -= sizeof(*fde) + *fde, fde += 1 + *fde / sizeof(*fde)) {
+ const u32 *cie = fde + 1 - fde[1] / sizeof(*fde);
+
+ if (!fde[1])
+ continue; /* this is a CIE */
+ ptr = (const u8 *)(fde + 2);
+ header->table[n].start = read_pointer(&ptr,
+ (const u8 *)(fde + 1) + *fde,
+ fde_pointer_type(cie));
+ header->table[n].fde = (unsigned long)fde;
+ ++n;
+ }
+ WARN_ON(n != header->fde_count);
+
+ sort(header->table,
+ n,
+ sizeof(*header->table),
+ cmp_eh_frame_hdr_table_entries,
+ swap_eh_frame_hdr_table_entries);
+
+ table->hdrsz = hdrSize;
+ smp_wmb();
+ table->header = (const void *)header;
+}
+
+static void *__init balloc(unsigned long sz)
+{
+ return __alloc_bootmem_nopanic(sz,
+ sizeof(unsigned int),
+ __pa(MAX_DMA_ADDRESS));
+}
+
+void __init unwind_setup(void)
+{
+ setup_unwind_table(&root_table, balloc);