scripts/sortextable: support objects with more than 64K sections.

Building with a large config and -ffunction-sections results in a large
number of sections and sortextable needs to be able to handle that.
Implement support for > 64K sections as modpost does.

Signed-off-by: Jamie Iles <jamie.iles@oracle.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Michal Marek <mmarek@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 24 insertions, 0 deletions

diff --git a/scripts/sortextable.c b/scripts/sortextable.c
index 7c2310c5b99..5f7a8b663cb 100644
--- a/scripts/sortextable.c
+++ b/scripts/sortextable.c
@@ -152,6 +152,30 @@ static void (*w2)(uint16_t, uint16_t *);
 
 typedef void (*table_sort_t)(char *, int);
 
+/*
+ * Move reserved section indices SHN_LORESERVE..SHN_HIRESERVE out of
+ * the way to -256..-1, to avoid conflicting with real section
+ * indices.
+ */
+#define SPECIAL(i) ((i) - (SHN_HIRESERVE + 1))
+
+static inline int is_shndx_special(unsigned int i)
+{
+	return i != SHN_XINDEX && i >= SHN_LORESERVE && i <= SHN_HIRESERVE;
+}
+
+/* Accessor for sym->st_shndx, hides ugliness of "64k sections" */
+static inline unsigned int get_secindex(unsigned int shndx,
+					unsigned int sym_offs,
+					const Elf32_Word *symtab_shndx_start)
+{
+	if (is_shndx_special(shndx))
+		return SPECIAL(shndx);
+	if (shndx != SHN_XINDEX)
+		return shndx;
+	return r(&symtab_shndx_start[sym_offs]);
+}
+
 /* 32 bit and 64 bit are very similar */
 #include "sortextable.h"
 #define SORTEXTABLE_64