flat: use IS_ERR_VALUE() helper macro

There is a common macro now for testing mixed pointer/errno values, so use
that rather than handling the casts ourself.

Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Acked-by: David McCullough <david_mccullough@securecomputing.com>
Acked-by: Greg Ungerer <gerg@uclinux.org>
Cc: David Howells <dhowells@redhat.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

fs/binfmt_flat.c

@@ -278,8 +278,6 @@ static int decompress_exec(
 		ret = bprm->file->f_op->read(bprm->file, buf, LBUFSIZE, &fpos);
 		if (ret <= 0)
 			break;
-		if (ret >= (unsigned long) -4096)
-			break;
 		len -= ret;
 
 		strm.next_in = buf;
@@ -335,7 +333,7 @@ calc_reloc(unsigned long r, struct lib_info *p, int curid, int internalp)
 					"(%d != %d)", (unsigned) r, curid, id);
 			goto failed;
 		} else if ( ! p->lib_list[id].loaded &&
-				load_flat_shared_library(id, p) > (unsigned long) -4096) {
+				IS_ERR_VALUE(load_flat_shared_library(id, p))) {
 			printk("BINFMT_FLAT: failed to load library %d", id);
 			goto failed;
 		}
@@ -545,7 +543,7 @@ static int load_flat_file(struct linux_binprm * bprm,
 		textpos = do_mmap(bprm->file, 0, text_len, PROT_READ|PROT_EXEC,
 				  MAP_PRIVATE|MAP_EXECUTABLE, 0);
 		up_write(&current->mm->mmap_sem);
-		if (!textpos  || textpos >= (unsigned long) -4096) {
+		if (!textpos || IS_ERR_VALUE(textpos)) {
 			if (!textpos)
 				textpos = (unsigned long) -ENOMEM;
 			printk("Unable to mmap process text, errno %d\n", (int)-textpos);
@@ -560,7 +558,7 @@ static int load_flat_file(struct linux_binprm * bprm,
 			PROT_READ|PROT_WRITE|PROT_EXEC, MAP_PRIVATE, 0);
 		up_write(&current->mm->mmap_sem);
 
-		if (realdatastart == 0 || realdatastart >= (unsigned long)-4096) {
+		if (realdatastart == 0 || IS_ERR_VALUE(realdatastart)) {
 			if (!realdatastart)
 				realdatastart = (unsigned long) -ENOMEM;
 			printk("Unable to allocate RAM for process data, errno %d\n",
@@ -587,7 +585,7 @@ static int load_flat_file(struct linux_binprm * bprm,
 			result = bprm->file->f_op->read(bprm->file, (char *) datapos,
 					data_len + (relocs * sizeof(unsigned long)), &fpos);
 		}
-		if (result >= (unsigned long)-4096) {
+		if (IS_ERR_VALUE(result)) {
 			printk("Unable to read data+bss, errno %d\n", (int)-result);
 			do_munmap(current->mm, textpos, text_len);
 			do_munmap(current->mm, realdatastart, data_len + extra);
@@ -607,7 +605,7 @@ static int load_flat_file(struct linux_binprm * bprm,
 			PROT_READ | PROT_EXEC | PROT_WRITE, MAP_PRIVATE, 0);
 		up_write(&current->mm->mmap_sem);
 
-		if (!textpos  || textpos >= (unsigned long) -4096) {
+		if (!textpos || IS_ERR_VALUE(textpos)) {
 			if (!textpos)
 				textpos = (unsigned long) -ENOMEM;
 			printk("Unable to allocate RAM for process text/data, errno %d\n",
@@ -641,7 +639,7 @@ static int load_flat_file(struct linux_binprm * bprm,
 			fpos = 0;
 			result = bprm->file->f_op->read(bprm->file,
 					(char *) textpos, text_len, &fpos);
-			if (result < (unsigned long) -4096)
+			if (!IS_ERR_VALUE(result))
 				result = decompress_exec(bprm, text_len, (char *) datapos,
 						 data_len + (relocs * sizeof(unsigned long)), 0);
 		}
@@ -651,13 +649,13 @@ static int load_flat_file(struct linux_binprm * bprm,
 			fpos = 0;
 			result = bprm->file->f_op->read(bprm->file,
 					(char *) textpos, text_len, &fpos);
-			if (result < (unsigned long) -4096) {
+			if (!IS_ERR_VALUE(result)) {
 				fpos = ntohl(hdr->data_start);
 				result = bprm->file->f_op->read(bprm->file, (char *) datapos,
 					data_len + (relocs * sizeof(unsigned long)), &fpos);
 			}
 		}
-		if (result >= (unsigned long)-4096) {
+		if (IS_ERR_VALUE(result)) {
 			printk("Unable to read code+data+bss, errno %d\n",(int)-result);
 			do_munmap(current->mm, textpos, text_len + data_len + extra +
 				MAX_SHARED_LIBS * sizeof(unsigned long));
@@ -835,7 +833,7 @@ static int load_flat_shared_library(int id, struct lib_info *libs)
 
 	res = prepare_binprm(&bprm);
 
-	if (res <= (unsigned long)-4096)
+	if (!IS_ERR_VALUE(res))
 		res = load_flat_file(&bprm, libs, id, NULL);
 
 	abort_creds(bprm.cred);
@@ -880,7 +878,7 @@ static int load_flat_binary(struct linux_binprm * bprm, struct pt_regs * regs)
 	stack_len += FLAT_DATA_ALIGN - 1;  /* reserve for upcoming alignment */
 	
 	res = load_flat_file(bprm, &libinfo, 0, &stack_len);
-	if (res > (unsigned long)-4096)
+	if (IS_ERR_VALUE(res))
 		return res;
 	
 	/* Update data segment pointers for all libraries */