mm: remove more IS_ERR_VALUE abuses

The do_brk() and vm_brk() return value was "unsigned long" and returned
the starting address on success, and an error value on failure.  The
reasons are entirely historical, and go back to it basically behaving
like the mmap() interface does.

However, nobody actually wanted that interface, and it causes totally
pointless IS_ERR_VALUE() confusion.

What every single caller actually wants is just the simpler integer
return of zero for success and negative error number on failure.

So just convert to that much clearer and more common calling convention,
and get rid of all the IS_ERR_VALUE() uses wrt vm_brk().

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 8 insertions, 9 deletions

diff --git a/arch/x86/ia32/ia32_aout.c b/arch/x86/ia32/ia32_aout.c
index f5e737ff0022..cb26f18d43af 100644
--- a/arch/x86/ia32/ia32_aout.c
+++ b/arch/x86/ia32/ia32_aout.c
@@ -116,12 +116,12 @@ static struct linux_binfmt aout_format = {
 	.min_coredump	= PAGE_SIZE
 };
 
-static unsigned long set_brk(unsigned long start, unsigned long end)
+static int set_brk(unsigned long start, unsigned long end)
 {
 	start = PAGE_ALIGN(start);
 	end = PAGE_ALIGN(end);
 	if (end <= start)
-		return start;
+		return 0;
 	return vm_brk(start, end - start);
 }
 
@@ -321,7 +321,7 @@ static int load_aout_binary(struct linux_binprm *bprm)
 
 		error = vm_brk(text_addr & PAGE_MASK, map_size);
 
-		if (error != (text_addr & PAGE_MASK))
+		if (error)
 			return error;
 
 		error = read_code(bprm->file, text_addr, 32,
@@ -350,7 +350,7 @@ static int load_aout_binary(struct linux_binprm *bprm)
 
 		if (!bprm->file->f_op->mmap || (fd_offset & ~PAGE_MASK) != 0) {
 			error = vm_brk(N_TXTADDR(ex), ex.a_text+ex.a_data);
-			if (IS_ERR_VALUE(error))
+			if (error)
 				return error;
 
 			read_code(bprm->file, N_TXTADDR(ex), fd_offset,
@@ -378,7 +378,7 @@ static int load_aout_binary(struct linux_binprm *bprm)
 
 beyond_if:
 	error = set_brk(current->mm->start_brk, current->mm->brk);
-	if (IS_ERR_VALUE(error))
+	if (error)
 		return error;
 
 	set_binfmt(&aout_format);
@@ -441,7 +441,7 @@ static int load_aout_library(struct file *file)
 		}
 #endif
 		retval = vm_brk(start_addr, ex.a_text + ex.a_data + ex.a_bss);
-		if (IS_ERR_VALUE(retval))
+		if (retval)
 			goto out;
 
 		read_code(file, start_addr, N_TXTOFF(ex),
@@ -461,9 +461,8 @@ static int load_aout_library(struct file *file)
 	len = PAGE_ALIGN(ex.a_text + ex.a_data);
 	bss = ex.a_text + ex.a_data + ex.a_bss;
 	if (bss > len) {
-		error = vm_brk(start_addr + len, bss - len);
-		retval = error;
-		if (error != start_addr + len)
+		retval = vm_brk(start_addr + len, bss - len);
+		if (retval)
 			goto out;
 	}
 	retval = 0;