btrfs: cleanup 64bit/32bit divs, compile time constants

Switch to div_u64 if the divisor is a numeric constant or sum of
sizeof()s. We can remove a few instances of do_div that has the hidden
semtantics of changing the 1st argument.

Small power-of-two divisors are converted to bitshifts, large values are
kept intact for clarity.

Signed-off-by: David Sterba <dsterba@suse.cz>

diff --git a/fs/btrfs/dev-replace.c b/fs/btrfs/dev-replace.c
index 5ec03d9..0573848 100644 (file)
--- a/fs/btrfs/dev-replace.c
+++ b/fs/btrfs/dev-replace.c
@@ -670,8 +670,8 @@ void btrfs_dev_replace_status(struct btrfs_fs_info *fs_info,
        case BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED:
        case BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED:
                srcdev = dev_replace->srcdev;
-               args->status.progress_1000 = div64_u64(dev_replace->cursor_left,
-                       div64_u64(btrfs_device_get_total_bytes(srcdev), 1000));
+               args->status.progress_1000 = div_u64(dev_replace->cursor_left,
+                       div_u64(btrfs_device_get_total_bytes(srcdev), 1000));
                break;
        }
        btrfs_dev_replace_unlock(dev_replace);
@@ -806,7 +806,7 @@ static int btrfs_dev_replace_kthread(void *data)
                btrfs_dev_replace_status(fs_info, status_args);
                progress = status_args->status.progress_1000;
                kfree(status_args);
-               do_div(progress, 10);
+               progress = div_u64(progress, 10);
                printk_in_rcu(KERN_INFO
                        "BTRFS: continuing dev_replace from %s (devid %llu) to %s @%u%%\n",
                        dev_replace->srcdev->missing ? "<missing disk>" :

diff --cc fs/btrfs/disk-io.c
Simple merge

diff --cc fs/btrfs/extent-tree.c
Simple merge

diff --cc fs/btrfs/free-space-cache.c
Simple merge

diff --cc fs/btrfs/math.h
Simple merge

diff --cc fs/btrfs/super.c
Simple merge