UBI: change cascade of ifs to switch statements

This patch improves readability and simplifies scanning code by changing a
long cascade of 'if' statements to a switch statement. This should presumably
be a little faster as well.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>

1 files changed, 32 insertions, 13 deletions

diff --git a/drivers/mtd/ubi/scan.c b/drivers/mtd/ubi/scan.c
index a15e9bcb6e77..9405e2420055 100644
--- a/drivers/mtd/ubi/scan.c
+++ b/drivers/mtd/ubi/scan.c
@@ -746,11 +746,18 @@ static int process_eb(struct ubi_device *ubi, struct ubi_scan_info *si,
         err = ubi_io_read_ec_hdr(ubi, pnum, ech, 0);
         if (err < 0)
                 return err;
-        else if (err == UBI_IO_BITFLIPS)
+        switch (err) {
+        case 0:
+                break;
+        case UBI_IO_BITFLIPS:
                 bitflips = 1;
-        else if (err == UBI_IO_FF || err == UBI_IO_FF_BITFLIPS)
+                break;
+        case UBI_IO_FF:
+        case UBI_IO_FF_BITFLIPS:
                 return add_to_list(si, pnum, UBI_SCAN_UNKNOWN_EC, &si->erase);
-        else if (err == UBI_IO_BAD_HDR_EBADMSG || err == UBI_IO_BAD_HDR) {
+        case UBI_IO_BAD_HDR_EBADMSG:
+                si->read_err_count += 1;
+        case UBI_IO_BAD_HDR:
                 /*
                  * We have to also look at the VID header, possibly it is not
                  * corrupted. Set %bitflips flag in order to make this PEB be
@@ -759,6 +766,10 @@ static int process_eb(struct ubi_device *ubi, struct ubi_scan_info *si,
                 ec_err = err;
                 ec = UBI_SCAN_UNKNOWN_EC;
                 bitflips = 1;
+                break;
+        default:
+                ubi_err("'ubi_io_read_ec_hdr()' returned unknown code %d", err);
+                return -EINVAL;
         }
 
         if (!ec_err) {
@@ -814,24 +825,32 @@ static int process_eb(struct ubi_device *ubi, struct ubi_scan_info *si,
         err = ubi_io_read_vid_hdr(ubi, pnum, vidh, 0);
         if (err < 0)
                 return err;
-        else if (err == UBI_IO_BITFLIPS)
+        switch (err) {
+        case 0:
+                break;
+        case UBI_IO_BITFLIPS:
                 bitflips = 1;
-        else if (err == UBI_IO_BAD_HDR_EBADMSG || err == UBI_IO_BAD_HDR ||
-                 (err == UBI_IO_FF && ec_err) || err == UBI_IO_FF_BITFLIPS) {
-                /* VID header is corrupted */
-                if (err == UBI_IO_BAD_HDR_EBADMSG ||
-                    ec_err == UBI_IO_BAD_HDR_EBADMSG)
-                        si->read_err_count += 1;
+                break;
+        case UBI_IO_BAD_HDR_EBADMSG:
+                si->read_err_count += 1;
+        case UBI_IO_BAD_HDR:
+        case UBI_IO_FF_BITFLIPS:
                 err = add_to_list(si, pnum, ec, &si->corr);
                 if (err)
                         return err;
                 goto adjust_mean_ec;
-        } else if (err == UBI_IO_FF) {
-                /* No VID header - the physical eraseblock is free */
-                err = add_to_list(si, pnum, ec, &si->free);
+        case UBI_IO_FF:
+                if (ec_err)
+                        err = add_to_list(si, pnum, ec, &si->corr);
+                else
+                        err = add_to_list(si, pnum, ec, &si->free);
                 if (err)
                         return err;
                 goto adjust_mean_ec;
+        default:
+                ubi_err("'ubi_io_read_vid_hdr()' returned unknown code %d",
+                        err);
+                return -EINVAL;
         }
 
         vol_id = be32_to_cpu(vidh->vol_id);