ide: decrease size of ->pc_buf field in struct ide_atapi_pc

struct ide_atapi_pc is often allocated on the stack and size of ->pc_buf
size is 256 bytes.  However since only ide_floppy_create_read_capacity_cmd()
and idetape_create_inquiry_cmd() require such size allocate buffers for
these pc-s explicitely and decrease ->pc_buf size to 64 bytes.

Cc: Borislav Petkov <petkovbb@gmail.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
diff --git a/drivers/ide/ide-floppy_ioctl.c b/drivers/ide/ide-floppy_ioctl.c
index 8f8be85..cd8a420 100644
--- a/drivers/ide/ide-floppy_ioctl.c
+++ b/drivers/ide/ide-floppy_ioctl.c
@@ -36,9 +36,9 @@
 					    int __user *arg)
 {
 	struct ide_disk_obj *floppy = drive->driver_data;
-	u8 header_len, desc_cnt;
 	int i, blocks, length, u_array_size, u_index;
 	int __user *argp;
+	u8 pc_buf[256], header_len, desc_cnt;
 
 	if (get_user(u_array_size, arg))
 		return -EFAULT;
@@ -47,6 +47,9 @@
 		return -EINVAL;
 
 	ide_floppy_create_read_capacity_cmd(pc);
+	pc->buf = &pc_buf[0];
+	pc->buf_size = sizeof(pc_buf);
+
 	if (ide_queue_pc_tail(drive, floppy->disk, pc)) {
 		printk(KERN_ERR "ide-floppy: Can't get floppy parameters\n");
 		return -EIO;