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.

12 files changed, 24 insertions, 11 deletions

diff --git a/src/aio/aio_readwrite.c b/src/aio/aio_readwrite.c
index 666372db..0de3d4fb 100644
--- a/src/aio/aio_readwrite.c
+++ b/src/aio/aio_readwrite.c
@@ -2,8 +2,8 @@
 #include <fcntl.h>
 #include <errno.h>
 #include <unistd.h>
-#include <limits.h>
 #include "pthread_impl.h"
+#include "libc.h"
 
 static void dummy(void)
 {
diff --git a/src/aio/lio_listio.c b/src/aio/lio_listio.c
index 07145dd4..61d7f20e 100644
--- a/src/aio/lio_listio.c
+++ b/src/aio/lio_listio.c
@@ -1,9 +1,9 @@
 #include <aio.h>
 #include <errno.h>
-#include <limits.h>
 #include <unistd.h>
 #include <string.h>
 #include "pthread_impl.h"
+#include "libc.h"
 
 struct lio_state {
 	struct sigevent *sev;
diff --git a/src/conf/fpathconf.c b/src/conf/fpathconf.c
index bfbb2742..28c4345c 100644
--- a/src/conf/fpathconf.c
+++ b/src/conf/fpathconf.c
@@ -19,11 +19,11 @@ long fpathconf(int fd, int name)
 		[_PC_PRIO_IO] = -1,
 		[_PC_SOCK_MAXBUF] = -1,
 		[_PC_FILESIZEBITS] = FILESIZEBITS,
-		[_PC_REC_INCR_XFER_SIZE] = PAGE_SIZE,
-		[_PC_REC_MAX_XFER_SIZE] = PAGE_SIZE,
-		[_PC_REC_MIN_XFER_SIZE] = PAGE_SIZE,
-		[_PC_REC_XFER_ALIGN] = PAGE_SIZE,
-		[_PC_ALLOC_SIZE_MIN] = PAGE_SIZE,
+		[_PC_REC_INCR_XFER_SIZE] = 4096,
+		[_PC_REC_MAX_XFER_SIZE] = 4096,
+		[_PC_REC_MIN_XFER_SIZE] = 4096,
+		[_PC_REC_XFER_ALIGN] = 4096,
+		[_PC_ALLOC_SIZE_MIN] = 4096,
 		[_PC_SYMLINK_MAX] = SYMLINK_MAX,
 		[_PC_2_SYMLINKS] = 1
 	};
diff --git a/src/conf/sysconf.c b/src/conf/sysconf.c
index 5dc1e453..97fd4fad 100644
--- a/src/conf/sysconf.c
+++ b/src/conf/sysconf.c
@@ -3,6 +3,7 @@
 #include <errno.h>
 #include <sys/resource.h>
 #include "syscall.h"
+#include "libc.h"
 
 #define VER (-2)
 #define OFLOW (-3)
@@ -42,7 +43,7 @@ long sysconf(int name)
 		[_SC_MQ_OPEN_MAX] = -1,
 		[_SC_MQ_PRIO_MAX] = OFLOW,
 		[_SC_VERSION] = VER,
-		[_SC_PAGE_SIZE] = PAGE_SIZE,
+		[_SC_PAGE_SIZE] = OFLOW,
 		[_SC_RTSIG_MAX] = 63, /* ?? */
 		[_SC_SEM_NSEMS_MAX] = SEM_NSEMS_MAX,
 		[_SC_SEM_VALUE_MAX] = OFLOW,
@@ -222,6 +223,8 @@ long sysconf(int name)
 		if (name == _SC_ARG_MAX) return ARG_MAX;
 		if (name == _SC_SEM_VALUE_MAX) return SEM_VALUE_MAX;
 		if (name == _SC_MQ_PRIO_MAX) return MQ_PRIO_MAX;
+		/* name == _SC_PAGE_SIZE */
+		return PAGE_SIZE;
 	} else if (values[name] == CPUCNT) {
 		unsigned char set[128] = {1};
 		int i, cnt;
diff --git a/src/env/__libc_start_main.c b/src/env/__libc_start_main.c
index 2a8698bb..73d49327 100644
--- a/src/env/__libc_start_main.c
+++ b/src/env/__libc_start_main.c
@@ -26,6 +26,7 @@ void __init_libc(char **envp, char *pn)
 	for (i=0; auxv[i]; i+=2) if (auxv[i]<AUX_CNT) aux[auxv[i]] = auxv[i+1];
 	__hwcap = aux[AT_HWCAP];
 	__sysinfo = aux[AT_SYSINFO];
+	libc.page_size = aux[AT_PAGESZ];
 
 	if (pn) {
 		__progname = __progname_full = pn;
diff --git a/src/internal/libc.h b/src/internal/libc.h
index c8fbe3fd..3350b3d1 100644
--- a/src/internal/libc.h
+++ b/src/internal/libc.h
@@ -3,6 +3,7 @@
 
 #include <stdlib.h>
 #include <stdio.h>
+#include <limits.h>
 
 struct __libc {
 	void *main_thread;
@@ -14,10 +15,15 @@ struct __libc {
 	FILE *ofl_head;
 	int ofl_lock[2];
 	size_t tls_size;
+	size_t page_size;
 };
 
 extern size_t __hwcap;
 
+#ifndef PAGE_SIZE
+#define PAGE_SIZE libc.page_size
+#endif
+
 #if !defined(__PIC__) || (100*__GNUC__+__GNUC_MINOR__ >= 303 && !defined(__PCC__))
 
 #ifdef __PIC__
diff --git a/src/ldso/dynlink.c b/src/ldso/dynlink.c
index a89e7432..a525b3d8 100644
--- a/src/ldso/dynlink.c
+++ b/src/ldso/dynlink.c
@@ -980,6 +980,7 @@ void *__dynlink(int argc, char **argv)
 		env_preload = 0;
 		libc.secure = 1;
 	}
+	libc.page_size = aux[AT_PAGESZ];
 
 	/* If the dynamic linker was invoked as a program itself, AT_BASE
 	 * will not be set. In that case, we assume the base address is
diff --git a/src/legacy/getpagesize.c b/src/legacy/getpagesize.c
index 5ede652b..a47995cb 100644
--- a/src/legacy/getpagesize.c
+++ b/src/legacy/getpagesize.c
@@ -1,5 +1,5 @@
 #include <unistd.h>
-#include <limits.h>
+#include "libc.h"
 
 int getpagesize(void)
 {
diff --git a/src/legacy/valloc.c b/src/legacy/valloc.c
index e48cf214..5af2256a 100644
--- a/src/legacy/valloc.c
+++ b/src/legacy/valloc.c
@@ -1,6 +1,6 @@
 #define _BSD_SOURCE
 #include <stdlib.h>
-#include <limits.h>
+#include "libc.h"
 
 void *valloc(size_t size)
 {
diff --git a/src/mman/mprotect.c b/src/mman/mprotect.c
index 5ab2d8b0..f488486d 100644
--- a/src/mman/mprotect.c
+++ b/src/mman/mprotect.c
@@ -1,5 +1,5 @@
 #include <sys/mman.h>
-#include <limits.h>
+#include "libc.h"
 #include "syscall.h"
 
 int mprotect(void *addr, size_t len, int prot)
diff --git a/src/thread/pthread_create.c b/src/thread/pthread_create.c
index 6c841be7..d26f252e 100644
--- a/src/thread/pthread_create.c
+++ b/src/thread/pthread_create.c
@@ -1,5 +1,6 @@
 #include "pthread_impl.h"
 #include "stdio_impl.h"
+#include "libc.h"
 #include <sys/mman.h>
 
 static void dummy_0()
diff --git a/src/thread/pthread_getattr_np.c b/src/thread/pthread_getattr_np.c
index 86df1def..10ea5127 100644
--- a/src/thread/pthread_getattr_np.c
+++ b/src/thread/pthread_getattr_np.c
@@ -1,5 +1,6 @@
 #define _GNU_SOURCE
 #include "pthread_impl.h"
+#include "libc.h"
 #include <sys/mman.h>
 
 int pthread_getattr_np(pthread_t t, pthread_attr_t *a)