support configurable page size on mips, powerpc and microblaze

PAGE_SIZE was hardcoded to 4096, which is historically what most
systems use, but on several archs it is a kernel config parameter,
user space can only know it at execution time from the aux vector.

PAGE_SIZE and PAGESIZE are not defined on archs where page size is
a runtime parameter, applications should use sysconf(_SC_PAGE_SIZE)
to query it. Internally libc code defines PAGE_SIZE to libc.page_size,
which is set to aux[AT_PAGESZ] in __init_libc and early in __dynlink
as well. (Note that libc.page_size can be accessed without GOT, ie.
before relocations are done)

Some fpathconf settings are hardcoded to 4096, these should be actually
queried from the filesystem using statfs.

2 files changed, 1 insertions, 2 deletions

diff --git a/arch/mips/bits/limits.h b/arch/mips/bits/limits.h
index 65a3dd64..fbc6d238 100644
--- a/arch/mips/bits/limits.h
+++ b/arch/mips/bits/limits.h
@@ -1,6 +1,5 @@
 #if defined(_POSIX_SOURCE) || defined(_POSIX_C_SOURCE) \
  || defined(_XOPEN_SOURCE) || defined(_GNU_SOURCE) || defined(_BSD_SOURCE)
-#define PAGE_SIZE 4096
 #define LONG_BIT 32
 #endif
 
diff --git a/arch/mips/reloc.h b/arch/mips/reloc.h
index 4c035f32..07fa10a7 100644
--- a/arch/mips/reloc.h
+++ b/arch/mips/reloc.h
@@ -51,7 +51,7 @@ void __reloc_self(int c, size_t *a, size_t *dynv, size_t *got)
 	for (a+=c+1; *a; a++);
 	for (a++; *a; a+=2) if (*a<20) t[*a] = a[1];
 	base = (char *)t[AT_BASE];
-	if (!base) base = (char *)(t[AT_PHDR] & -4096);
+	if (!base) base = (char *)(t[AT_PHDR] & -t[AT_PAGESZ]);
 	for (a=dynv; *a; a+=2) if (*a-0x70000000UL<20) t[*a&31] = a[1];
 	n = t[DT_MIPS_LOCAL_GOTNO - 0x70000000];
 	for (a=got; n; a++, n--) *a += (size_t)base;