gfs2: Turn gfs2_extent_map into gfs2_{get,alloc}_extent

Convert gfs2_extent_map to iomap and split it into gfs2_get_extent and
gfs2_alloc_extent.  Instead of hardcoding the extent size, pass it in
via the extlen parameter.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>

fs/gfs2/bmap.c

@@ -1320,28 +1320,47 @@ int gfs2_block_map(struct inode *inode, sector_t lblock,
 	return ret;
 }
 
-/*
- * Deprecated: do not use in new code
- */
-int gfs2_extent_map(struct inode *inode, u64 lblock, int *new, u64 *dblock, unsigned *extlen)
+int gfs2_get_extent(struct inode *inode, u64 lblock, u64 *dblock,
+		    unsigned int *extlen)
 {
-	struct buffer_head bh = { .b_state = 0, .b_blocknr = 0 };
+	unsigned int blkbits = inode->i_blkbits;
+	struct iomap iomap = { };
+	unsigned int len;
 	int ret;
-	int create = *new;
-
-	BUG_ON(!extlen);
-	BUG_ON(!dblock);
-	BUG_ON(!new);
-
-	bh.b_size = BIT(inode->i_blkbits + (create ? 0 : 5));
-	ret = gfs2_block_map(inode, lblock, &bh, create);
-	*extlen = bh.b_size >> inode->i_blkbits;
-	*dblock = bh.b_blocknr;
-	if (buffer_new(&bh))
-		*new = 1;
-	else
-		*new = 0;
+
+	ret = gfs2_iomap_get(inode, lblock << blkbits, *extlen << blkbits,
+			     &iomap);
+	if (ret)
+		return ret;
+	if (iomap.type != IOMAP_MAPPED)
+		return -EIO;
+	*dblock = iomap.addr >> blkbits;
+	len = iomap.length >> blkbits;
+	if (len < *extlen)
+		*extlen = len;
+	return 0;
+}
+
+int gfs2_alloc_extent(struct inode *inode, u64 lblock, u64 *dblock,
+		      unsigned int *extlen, bool *new)
+{
+	unsigned int blkbits = inode->i_blkbits;
+	struct iomap iomap = { };
+	unsigned int len;
+	int ret;
+
+	ret = gfs2_iomap_alloc(inode, lblock << blkbits, *extlen << blkbits,
+			       &iomap);
+	if (ret)
 		return ret;
+	if (iomap.type != IOMAP_MAPPED)
+		return -EIO;
+	*dblock = iomap.addr >> blkbits;
+	len = iomap.length >> blkbits;
+	if (len < *extlen)
+		*extlen = len;
+	*new = iomap.flags & IOMAP_F_NEW;
+	return 0;
 }
 
 /*

fs/gfs2/bmap.h

@@ -53,8 +53,10 @@ extern int gfs2_iomap_get(struct inode *inode, loff_t pos, loff_t length,
 			  struct iomap *iomap);
 extern int gfs2_iomap_alloc(struct inode *inode, loff_t pos, loff_t length,
 			    struct iomap *iomap);
-extern int gfs2_extent_map(struct inode *inode, u64 lblock, int *new,
-			   u64 *dblock, unsigned *extlen);
+extern int gfs2_get_extent(struct inode *inode, u64 lblock, u64 *dblock,
+			   unsigned int *extlen);
+extern int gfs2_alloc_extent(struct inode *inode, u64 lblock, u64 *dblock,
+			     unsigned *extlen, bool *new);
 extern int gfs2_setattr_size(struct inode *inode, u64 size);
 extern void gfs2_trim_blocks(struct inode *inode);
 extern int gfs2_truncatei_resume(struct gfs2_inode *ip);

fs/gfs2/dir.c

@@ -159,7 +159,7 @@ static int gfs2_dir_write_data(struct gfs2_inode *ip, const char *buf,
 	unsigned int o;
 	int copied = 0;
 	int error = 0;
-	int new = 0;
+	bool new = false;
 
 	if (!size)
 		return 0;
@@ -189,9 +189,9 @@ static int gfs2_dir_write_data(struct gfs2_inode *ip, const char *buf,
 			amount = sdp->sd_sb.sb_bsize - o;
 
 		if (!extlen) {
-			new = 1;
-			error = gfs2_extent_map(&ip->i_inode, lblock, &new,
-						&dblock, &extlen);
+			extlen = 1;
+			error = gfs2_alloc_extent(&ip->i_inode, lblock, &dblock,
+						  &extlen, &new);
 			if (error)
 				goto fail;
 			error = -EIO;
@@ -286,15 +286,14 @@ static int gfs2_dir_read_data(struct gfs2_inode *ip, __be64 *buf,
 	while (copied < size) {
 		unsigned int amount;
 		struct buffer_head *bh;
-		int new;
 
 		amount = size - copied;
 		if (amount > sdp->sd_sb.sb_bsize - o)
 			amount = sdp->sd_sb.sb_bsize - o;
 
 		if (!extlen) {
-			new = 0;
-			error = gfs2_extent_map(&ip->i_inode, lblock, &new,
+			extlen = 32;
+			error = gfs2_get_extent(&ip->i_inode, lblock,
 						&dblock, &extlen);
 			if (error || !dblock)
 				goto fail;

fs/gfs2/quota.c

@@ -1375,8 +1375,8 @@ int gfs2_quota_init(struct gfs2_sbd *sdp)
 		unsigned int y;
 
 		if (!extlen) {
-			int new = 0;
-			error = gfs2_extent_map(&ip->i_inode, x, &new, &dblock, &extlen);
+			extlen = 32;
+			error = gfs2_get_extent(&ip->i_inode, x, &dblock, &extlen);
 			if (error)
 				goto fail;
 		}

fs/gfs2/recovery.c

@@ -34,12 +34,12 @@ int gfs2_replay_read_block(struct gfs2_jdesc *jd, unsigned int blk,
 {
 	struct gfs2_inode *ip = GFS2_I(jd->jd_inode);
 	struct gfs2_glock *gl = ip->i_gl;
-	int new = 0;
 	u64 dblock;
 	u32 extlen;
 	int error;
 
-	error = gfs2_extent_map(&ip->i_inode, blk, &new, &dblock, &extlen);
+	extlen = 32;
+	error = gfs2_get_extent(&ip->i_inode, blk, &dblock, &extlen);
 	if (error)
 		return error;
 	if (!dblock) {