dedup

commit baf29fa2203239eb1767c97b48e093364c7c9f46
parent 00d03339c89087d34d11f3147daae28de6f94c7a
Author: sin <sin@2f30.org>
Date:   Thu, 25 Apr 2019 22:46:18 +0100

Add some comments to bsrm()

Diffstat:
M
bstorage.c
 | 
6
++++++

1 file changed, 6 insertions(+), 0 deletions(-)
diff --git a/bstorage.c b/bstorage.c
@@ -538,6 +538,7 @@ bsget(struct bctx *bctx, unsigned char *md, void *buf, size_t *n)
 	return 0;
 }
 
+/* Remove a block with the given hash */
 static int
 bsrm(struct bctx *bctx, unsigned char *md)
 {
@@ -568,6 +569,11 @@ bsrm(struct bctx *bctx, unsigned char *md)
 
 		mode = FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE;
 		if (fallocate(sctx->fd, mode, bd->offset, bd->size) < 0) {
+			/*
+			 * Filesystem does not support hole punching.
+			 * Try to recover the block descriptor so we don't
+			 * lose track of the block.
+			 */
 			lseek(sctx->fd, bdoffs, SEEK_SET);
 			bd->refcnt++;
 			packbd(sctx->fd, bd);