dedup

commit d27c04494de59d32935865ca40915476d35b2c30
parent 8f5a4daf24872ef4bab13dc180ed4e693b4c5c8a
Author: sin <sin@2f30.org>
Date:   Fri, 26 Apr 2019 11:07:20 +0100

Implement block gc operation

Diffstat:
M
TODO
 | 
2
+-
M
bcompress.c
 | 
10
++++++++++
M
block.c
 | 
12
++++++++++++
M
block.h
 | 
2
++
M
bstorage.c
 | 
25
+++++++++++++++++++++++++

5 files changed, 50 insertions(+), 1 deletion(-)
diff --git a/TODO b/TODO
@@ -2,4 +2,4 @@ Use a ring buffer in the chunker (avoid memmove() call)
 Create a library archive out of the blake2b files and link with it
 pledge/unveil support
 Use flock() to avoid corruption
-Impelment dup-gc(1)
+Implement dup-gc(1)
diff --git a/bcompress.c b/bcompress.c
@@ -26,6 +26,7 @@ static int bcopen(struct bctx *bctx, char *path, int flags, int mode, struct bpa
 static int bcput(struct bctx *bctx, void *buf, size_t n, unsigned char *md);
 static int bcget(struct bctx *bctx, unsigned char *md, void *buf, size_t *n);
 static int bcrm(struct bctx *bctx, unsigned char *md);
+static int bcgc(struct bctx *bctx, unsigned char *md);
 static int bccheck(struct bctx *bctx, unsigned char *md);
 static int bcsync(struct bctx *bctx);
 static int bcclose(struct bctx *bctx);
@@ -36,6 +37,7 @@ static struct bops bops = {
 	.put = bcput,
 	.get = bcget,
 	.rm = bcrm,
+	.gc = bcgc,
 	.check = bccheck,
 	.sync = bcsync,
 	.close = bcclose,
@@ -248,6 +250,14 @@ bcrm(struct bctx *bctx, unsigned char *md)
 }
 
 static int
+bcgc(struct bctx *bctx, unsigned char *md)
+{
+	struct bops *bops = bstorageops();
+
+	return bops->gc(bctx, md);
+}
+
+static int
 bccheck(struct bctx *bctx, unsigned char *md)
 {
 	struct bops *bops = bstorageops();
diff --git a/block.c b/block.c
@@ -90,6 +90,18 @@ brm(struct bctx *bctx, unsigned char *md)
 }
 
 int
+bgc(struct bctx *bctx, unsigned char *md)
+{
+	struct bops *bops;
+
+	if (bctx == NULL || md == NULL)
+		return -1;
+
+	bops = bcompressops();
+	return bops->gc(bctx, md);
+}
+
+int
 bcheck(struct bctx *bctx, unsigned char *md)
 {
 	struct bops *bops;
diff --git a/block.h b/block.h
@@ -18,6 +18,7 @@ struct bops {
 	int (*put)(struct bctx *bctx, void *buf, size_t n, unsigned char *md);
 	int (*get)(struct bctx *bctx, unsigned char *md, void *buf, size_t *n);
 	int (*rm)(struct bctx *bctx, unsigned char *md);
+	int (*gc)(struct bctx *bctx, unsigned char *md);
 	int (*check)(struct bctx *bctx, unsigned char *md);
 	int (*sync)(struct bctx *bctx);
 	int (*close)(struct bctx *bctx);
@@ -29,6 +30,7 @@ extern int bopen(char *path, int flags, int mode, struct bparam *bpar, struct bc
 extern int bput(struct bctx *bctx, void *buf, size_t n, unsigned char *md);
 extern int bget(struct bctx *bctx, unsigned char *md, void *buf, size_t *n);
 extern int brm(struct bctx *bctx, unsigned char *md);
+extern int bgc(struct bctx *bctx, unsigned char *md);
 extern int bcheck(struct bctx *bctx, unsigned char *md);
 extern int bsync(struct bctx *bctx);
 extern int bclose(struct bctx *bctx);
diff --git a/bstorage.c b/bstorage.c
@@ -56,6 +56,7 @@ static int bsopen(struct bctx *bctx, char *path, int flags, int mode, struct bpa
 static int bsput(struct bctx *bctx, void *buf, size_t n, unsigned char *md);
 static int bsget(struct bctx *bctx, unsigned char *md, void *buf, size_t *n);
 static int bsrm(struct bctx *bctx, unsigned char *md);
+static int bsgc(struct bctx *bctx, unsigned char *md);
 static int bscheck(struct bctx *bctx, unsigned char *md);
 static int bssync(struct bctx *bctx);
 static int bsclose(struct bctx *bctx);
@@ -66,6 +67,7 @@ static struct bops bops = {
 	.put = bsput,
 	.get = bsget,
 	.rm = bsrm,
+	.gc = bsgc,
 	.check = bscheck,
 	.sync = bssync,
 	.close = bsclose,
@@ -570,6 +572,29 @@ bsrm(struct bctx *bctx, unsigned char *md)
 	return 0;
 }
 
+static int
+bsgc(struct bctx *bctx, unsigned char *md)
+{
+	struct sctx *sctx;
+	struct bd key, *bd;
+
+	sctx = bctx->sctx;
+
+	/* Lookup block in the cache */
+	memcpy(key.md, md, MDSIZE);
+	bd = RB_FIND(bdcache, &sctx->bdcache, &key);
+	if (bd == NULL)
+		return -1;
+
+	/* Live block descriptor, nothing to do here */
+	if (bd->refcnt > 0)
+		return 0;
+
+	/* Re-punch the hole */
+	punchhole(sctx->fd, bd->offset, bd->size);
+	return 0;
+}
+
 /*
  * Lookup the block and rehash it.  Check that the
  * resulting hash matches the given hash.