[PATCH] Common compat_sys_sysinfo

I noticed that almost all architectures implemented exactly the same
sys32_sysinfo...  except parisc, where a bug was to be found in handling of
the uptime.  So let's remove a whole whack of code for fun and profit.
Cribbed compat_sys_sysinfo from x86_64's implementation, since I figured it
would be the best tested.

This patch incorporates Arnd's suggestion of not using set_fs/get_fs, but
instead extracting out the common code from sys_sysinfo.

Cc: Christoph Hellwig <hch@infradead.org>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2 files changed, 1 insertions, 67 deletions

diff --git a/arch/x86_64/ia32/ia32entry.S b/arch/x86_64/ia32/ia32entry.S
index b4aa875e175b..5f32cf4de5fb 100644
--- a/arch/x86_64/ia32/ia32entry.S
+++ b/arch/x86_64/ia32/ia32entry.S
@@ -515,7 +515,7 @@ ia32_sys_call_table:
 	.quad sys32_vm86_warning	/* vm86old */ 
 	.quad compat_sys_wait4
 	.quad sys_swapoff		/* 115 */
-	.quad sys32_sysinfo
+	.quad compat_sys_sysinfo
 	.quad sys32_ipc
 	.quad sys_fsync
 	.quad stub32_sigreturn
diff --git a/arch/x86_64/ia32/sys_ia32.c b/arch/x86_64/ia32/sys_ia32.c
index c9bac3af29d6..200fdde18d96 100644
--- a/arch/x86_64/ia32/sys_ia32.c
+++ b/arch/x86_64/ia32/sys_ia32.c
@@ -523,72 +523,6 @@ sys32_sysfs(int option, u32 arg1, u32 arg2)
 	return sys_sysfs(option, arg1, arg2);
 }
 
-struct sysinfo32 {
-        s32 uptime;
-        u32 loads[3];
-        u32 totalram;
-        u32 freeram;
-        u32 sharedram;
-        u32 bufferram;
-        u32 totalswap;
-        u32 freeswap;
-        unsigned short procs;
-	unsigned short pad; 
-        u32 totalhigh;
-        u32 freehigh;
-        u32 mem_unit;
-        char _f[20-2*sizeof(u32)-sizeof(int)];
-};
-
-asmlinkage long
-sys32_sysinfo(struct sysinfo32 __user *info)
-{
-	struct sysinfo s;
-	int ret;
-	mm_segment_t old_fs = get_fs ();
-	int bitcount = 0;
-	
-	set_fs (KERNEL_DS);
-	ret = sys_sysinfo((struct sysinfo __user *)&s);
-	set_fs (old_fs);
-
-        /* Check to see if any memory value is too large for 32-bit and scale
-	 *  down if needed
-	 */
-	if ((s.totalram >> 32) || (s.totalswap >> 32)) {
-		while (s.mem_unit < PAGE_SIZE) {
-			s.mem_unit <<= 1;
-			bitcount++;
-		}
-		s.totalram >>= bitcount;
-		s.freeram >>= bitcount;
-		s.sharedram >>= bitcount;
-		s.bufferram >>= bitcount;
-		s.totalswap >>= bitcount;
-		s.freeswap >>= bitcount;
-		s.totalhigh >>= bitcount;
-		s.freehigh >>= bitcount;
-	}
-
-	if (!access_ok(VERIFY_WRITE, info, sizeof(struct sysinfo32)) ||
-	    __put_user (s.uptime, &info->uptime) ||
-	    __put_user (s.loads[0], &info->loads[0]) ||
-	    __put_user (s.loads[1], &info->loads[1]) ||
-	    __put_user (s.loads[2], &info->loads[2]) ||
-	    __put_user (s.totalram, &info->totalram) ||
-	    __put_user (s.freeram, &info->freeram) ||
-	    __put_user (s.sharedram, &info->sharedram) ||
-	    __put_user (s.bufferram, &info->bufferram) ||
-	    __put_user (s.totalswap, &info->totalswap) ||
-	    __put_user (s.freeswap, &info->freeswap) ||
-	    __put_user (s.procs, &info->procs) ||
-	    __put_user (s.totalhigh, &info->totalhigh) || 
-	    __put_user (s.freehigh, &info->freehigh) ||
-	    __put_user (s.mem_unit, &info->mem_unit))
-		return -EFAULT;
-	return 0;
-}
-                
 asmlinkage long
 sys32_sched_rr_get_interval(compat_pid_t pid, struct compat_timespec __user *interval)
 {