new helper: read_code()

switch binfmts that use ->read() to that (and to kernel_read()
in several cases in binfmt_flat - sure, it's nommu, but still,
doing ->read() into kmalloc'ed buffer...)

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/binfmt_aout.c b/fs/binfmt_aout.c
index bbc8f88..b23253d 100644
--- a/fs/binfmt_aout.c
+++ b/fs/binfmt_aout.c
@@ -287,15 +287,12 @@
 			return error;
 		}
 
-		error = bprm->file->f_op->read(bprm->file,
-			  (char __user *)text_addr,
-			  ex.a_text+ex.a_data, &pos);
+		error = read_code(bprm->file, text_addr, pos,
+				  ex.a_text+ex.a_data);
 		if ((signed long)error < 0) {
 			send_sig(SIGKILL, current, 0);
 			return error;
 		}
-			 
-		flush_icache_range(text_addr, text_addr+ex.a_text+ex.a_data);
 	} else {
 		if ((ex.a_text & 0xfff || ex.a_data & 0xfff) &&
 		    (N_MAGIC(ex) != NMAGIC) && printk_ratelimit())
@@ -311,14 +308,9 @@
 		}
 
 		if (!bprm->file->f_op->mmap||((fd_offset & ~PAGE_MASK) != 0)) {
-			loff_t pos = fd_offset;
 			vm_brk(N_TXTADDR(ex), ex.a_text+ex.a_data);
-			bprm->file->f_op->read(bprm->file,
-					(char __user *)N_TXTADDR(ex),
-					ex.a_text+ex.a_data, &pos);
-			flush_icache_range((unsigned long) N_TXTADDR(ex),
-					   (unsigned long) N_TXTADDR(ex) +
-					   ex.a_text+ex.a_data);
+			read_code(bprm->file, N_TXTADDR(ex), fd_offset,
+				  ex.a_text + ex.a_data);
 			goto beyond_if;
 		}
 
@@ -397,8 +389,6 @@
 	start_addr =  ex.a_entry & 0xfffff000;
 
 	if ((N_TXTOFF(ex) & ~PAGE_MASK) != 0) {
-		loff_t pos = N_TXTOFF(ex);
-
 		if (printk_ratelimit())
 		{
 			printk(KERN_WARNING 
@@ -407,11 +397,8 @@
 		}
 		vm_brk(start_addr, ex.a_text + ex.a_data + ex.a_bss);
 		
-		file->f_op->read(file, (char __user *)start_addr,
-			ex.a_text + ex.a_data, &pos);
-		flush_icache_range((unsigned long) start_addr,
-				   (unsigned long) start_addr + ex.a_text + ex.a_data);
-
+		read_code(file, start_addr, N_TXTOFF(ex),
+			  ex.a_text + ex.a_data);
 		retval = 0;
 		goto out;
 	}