1 files changed, 257 insertions, 23 deletions

diff --git a/fs/gfs2/lops.c b/fs/gfs2/lops.c
index a065f766723..dd41863810d 100644
--- a/fs/gfs2/lops.c
+++ b/fs/gfs2/lops.c
@@ -428,49 +428,188 @@ static void rg_lo_after_commit(struct gfs2_sbd *sdp, struct gfs2_ail *ai)
 	gfs2_assert_warn(sdp, !sdp->sd_log_num_rg);
 }
 
+/**
+ * databuf_lo_add - Add a databuf to the transaction.
+ *
+ * This is used in two distinct cases:
+ * i) In ordered write mode
+ *    We put the data buffer on a list so that we can ensure that its
+ *    synced to disk at the right time
+ * ii) In journaled data mode
+ *    We need to journal the data block in the same way as metadata in
+ *    the functions above. The difference is that here we have a tag
+ *    which is two __be64's being the block number (as per meta data)
+ *    and a flag which says whether the data block needs escaping or
+ *    not. This means we need a new log entry for each 251 or so data
+ *    blocks, which isn't an enormous overhead but twice as much as
+ *    for normal metadata blocks.
+ */
 static void databuf_lo_add(struct gfs2_sbd *sdp, struct gfs2_log_element *le)
 {
-	get_transaction->tr_touched = 1;
+	struct gfs2_bufdata *bd = container_of(le, struct gfs2_bufdata, bd_le);
+	struct gfs2_trans *tr = get_transaction;
+	struct address_space *mapping = bd->bd_bh->b_page->mapping;
+	struct gfs2_inode *ip = get_v2ip(mapping->host);
 
+	tr->tr_touched = 1;
+	if (!list_empty(&bd->bd_list_tr) &&
+	    (ip->i_di.di_flags & GFS2_DIF_JDATA)) {
+		tr->tr_num_buf++;
+		gfs2_trans_add_gl(bd->bd_gl);
+		list_add(&bd->bd_list_tr, &tr->tr_list_buf);
+		gfs2_pin(sdp, bd->bd_bh);
+	} else {
+		clear_buffer_pinned(bd->bd_bh);
+	}
 	gfs2_log_lock(sdp);
+	if (ip->i_di.di_flags & GFS2_DIF_JDATA)
+		sdp->sd_log_num_jdata++;
 	sdp->sd_log_num_databuf++;
 	list_add(&le->le_list, &sdp->sd_log_le_databuf);
 	gfs2_log_unlock(sdp);
 }
 
+static int gfs2_check_magic(struct buffer_head *bh)
+{
+	struct page *page = bh->b_page;
+	void *kaddr;
+	__be32 *ptr;
+	int rv = 0;
+
+	kaddr = kmap_atomic(page, KM_USER0);
+	ptr = kaddr + bh_offset(bh);
+	if (*ptr == cpu_to_be32(GFS2_MAGIC))
+		rv = 1;
+	kunmap_atomic(page, KM_USER0);
+
+	return rv;
+}
+
+/**
+ * databuf_lo_before_commit - Scan the data buffers, writing as we go
+ *
+ * Here we scan through the lists of buffers and make the assumption
+ * that any buffer thats been pinned is being journaled, and that
+ * any unpinned buffer is an ordered write data buffer and therefore
+ * will be written back rather than journaled.
+ */
 static void databuf_lo_before_commit(struct gfs2_sbd *sdp)
 {
-	struct list_head *head = &sdp->sd_log_le_databuf;
 	LIST_HEAD(started);
-	struct gfs2_bufdata *bd;
-	struct buffer_head *bh;
+	struct gfs2_bufdata *bd1 = NULL, *bd2, *bdt;
+	struct buffer_head *bh = NULL;
+	unsigned int offset = sizeof(struct gfs2_log_descriptor);
+	struct gfs2_log_descriptor *ld;
+	unsigned int limit;
+	unsigned int total_dbuf = sdp->sd_log_num_databuf;
+	unsigned int total_jdata = sdp->sd_log_num_jdata;
+	unsigned int num, n;
+	__be64 *ptr;
 
-	while (!list_empty(head)) {
-		bd = list_entry(head->prev, struct gfs2_bufdata, bd_le.le_list);
-		list_move(&bd->bd_le.le_list, &started);
+	offset += (2*sizeof(__be64) - 1);
+	offset &= ~(2*sizeof(__be64) - 1);
+	limit = (sdp->sd_sb.sb_bsize - offset)/sizeof(__be64);
 
-		gfs2_log_lock(sdp);
-		bh = bd->bd_bh;
+	/* printk(KERN_INFO "totals: jdata=%u dbuf=%u\n", total_jdata, total_dbuf); */
+	/*
+	 * Start writing ordered buffers, write journaled buffers
+	 * into the log along with a header
+	 */
+	bd2 = bd1 = list_prepare_entry(bd1, &sdp->sd_log_le_databuf, bd_le.le_list);
+	while(total_dbuf) {
+		num = total_jdata;
+		if (num > limit)
+			num = limit;
+		n = 0;
+		list_for_each_entry_safe_continue(bd1, bdt, &sdp->sd_log_le_databuf, bd_le.le_list) {
+			gfs2_log_lock(sdp);
+			/* An ordered write buffer */
+			if (bd1->bd_bh && !buffer_pinned(bd1->bd_bh)) {
+				list_move(&bd1->bd_le.le_list, &started);
+				if (bd1 == bd2) {
+					bd2 = NULL;
+					bd2 = list_prepare_entry(bd2, &sdp->sd_log_le_databuf, bd_le.le_list);
+				}
+				total_dbuf--;
+				if (bd1->bd_bh) {
+					get_bh(bd1->bd_bh);
+					gfs2_log_unlock(sdp);
+					if (buffer_dirty(bd1->bd_bh)) {
+						wait_on_buffer(bd1->bd_bh);
+						ll_rw_block(WRITE, 1, &bd1->bd_bh);
+					}
+					brelse(bd1->bd_bh);
+					continue;
+				}
+				gfs2_log_unlock(sdp);
+				continue;
+			} else if (bd1->bd_bh) { /* A journaled buffer */
+				int magic;
+				gfs2_log_unlock(sdp);
+				/* printk(KERN_INFO "journaled buffer\n"); */
+				if (!bh) {
+					bh = gfs2_log_get_buf(sdp);
+					ld = (struct gfs2_log_descriptor *)bh->b_data;
+					ptr = (__be64 *)(bh->b_data + offset);
+					ld->ld_header.mh_magic = cpu_to_be32(GFS2_MAGIC);
+					ld->ld_header.mh_type = cpu_to_be16(GFS2_METATYPE_LD);
+					ld->ld_header.mh_format = cpu_to_be16(GFS2_FORMAT_LD);
+					ld->ld_type = cpu_to_be32(GFS2_LOG_DESC_JDATA);
+					ld->ld_length = cpu_to_be32(num + 1);
+					ld->ld_data1 = cpu_to_be32(num);
+					ld->ld_data2 = cpu_to_be32(0);
+					memset(ld->ld_reserved, 0, sizeof(ld->ld_reserved));
+				}
+				magic = gfs2_check_magic(bd1->bd_bh);
+				*ptr++ = cpu_to_be64(bd1->bd_bh->b_blocknr);
+				*ptr++ = cpu_to_be64((__u64)magic);
+				clear_buffer_escaped(bd1->bd_bh);
+				if (unlikely(magic != 0))
+					set_buffer_escaped(bd1->bd_bh);
+				if (n++ > num)
+					break;
+			}
+		}
 		if (bh) {
-			get_bh(bh);
-			gfs2_log_unlock(sdp);
-			if (buffer_dirty(bh)) {
-				wait_on_buffer(bh);
-				ll_rw_block(WRITE, 1, &bh);
+			set_buffer_dirty(bh);
+			ll_rw_block(WRITE, 1, &bh);
+			bh = NULL;
+		}
+		n = 0;
+		/* printk(KERN_INFO "totals2: jdata=%u dbuf=%u\n", total_jdata, total_dbuf); */
+		list_for_each_entry_continue(bd2, &sdp->sd_log_le_databuf, bd_le.le_list) {
+			if (!bd2->bd_bh)
+				continue;
+			/* copy buffer if it needs escaping */
+			if (unlikely(buffer_escaped(bd2->bd_bh))) {
+				void *kaddr;
+				struct page *page = bd2->bd_bh->b_page;
+				bh = gfs2_log_get_buf(sdp);
+				kaddr = kmap_atomic(page, KM_USER0);
+				memcpy(bh->b_data, kaddr + bh_offset(bd2->bd_bh), sdp->sd_sb.sb_bsize);
+				kunmap_atomic(page, KM_USER0);
+				*(__be32 *)bh->b_data = 0;
+			} else {
+				bh = gfs2_log_fake_buf(sdp, bd2->bd_bh);
 			}
-			brelse(bh);
-		} else
-			gfs2_log_unlock(sdp);
+			set_buffer_dirty(bh);
+			ll_rw_block(WRITE, 1, &bh);
+			if (++n >= num)
+				break;
+		}
+		bh = NULL;
+		total_dbuf -= num;
+		total_jdata -= num;
 	}
-
+	/* printk(KERN_INFO "wait on ordered data buffers\n"); */
+	/* Wait on all ordered buffers */
 	while (!list_empty(&started)) {
-		bd = list_entry(started.next, struct gfs2_bufdata,
-				bd_le.le_list);
-		list_del(&bd->bd_le.le_list);
+		bd1 = list_entry(started.next, struct gfs2_bufdata, bd_le.le_list);
+		list_del(&bd1->bd_le.le_list);
 		sdp->sd_log_num_databuf--;
 
 		gfs2_log_lock(sdp);
-		bh = bd->bd_bh;
+		bh = bd1->bd_bh;
 		if (bh) {
 			set_v2bd(bh, NULL);
 			gfs2_log_unlock(sdp);
@@ -479,12 +618,103 @@ static void databuf_lo_before_commit(struct gfs2_sbd *sdp)
 		} else
 			gfs2_log_unlock(sdp);
 
-		kfree(bd);
+		kfree(bd1);
 	}
 
+	/* printk(KERN_INFO "sd_log_num_databuf %u sd_log_num_jdata %u\n", sdp->sd_log_num_databuf, sdp->sd_log_num_jdata); */
+	/* We've removed all the ordered write bufs here, so only jdata left */
+	gfs2_assert_warn(sdp, sdp->sd_log_num_databuf == sdp->sd_log_num_jdata);
+}
+
+static int databuf_lo_scan_elements(struct gfs2_jdesc *jd, unsigned int start,
+				    struct gfs2_log_descriptor *ld,
+				    __be64 *ptr, int pass)
+{
+	struct gfs2_sbd *sdp = jd->jd_inode->i_sbd;
+	struct gfs2_glock *gl = jd->jd_inode->i_gl;
+	unsigned int blks = be32_to_cpu(ld->ld_data1);
+	struct buffer_head *bh_log, *bh_ip;
+	uint64_t blkno;
+	uint64_t esc;
+	int error = 0;
+
+	if (pass != 1 || be32_to_cpu(ld->ld_type) != GFS2_LOG_DESC_JDATA)
+		return 0;
+
+	gfs2_replay_incr_blk(sdp, &start);
+	for (; blks; gfs2_replay_incr_blk(sdp, &start), blks--) {
+		blkno = be64_to_cpu(*ptr++);
+		esc = be64_to_cpu(*ptr++);
+
+		sdp->sd_found_blocks++;
+
+		if (gfs2_revoke_check(sdp, blkno, start))
+			continue;
+
+		error = gfs2_replay_read_block(jd, start, &bh_log);
+		if (error)
+			return error;
+
+		bh_ip = gfs2_meta_new(gl, blkno);
+		memcpy(bh_ip->b_data, bh_log->b_data, bh_log->b_size);
+
+		/* Unescape */
+		if (esc) {
+			__be32 *eptr = (__be32 *)bh_ip->b_data;
+			*eptr = cpu_to_be32(GFS2_MAGIC);
+		}
+		mark_buffer_dirty(bh_ip);
+
+		brelse(bh_log);
+		brelse(bh_ip);
+		if (error)
+			break;
+
+		sdp->sd_replayed_blocks++;
+	}
+
+	return error;
+}
+
+/* FIXME: sort out accounting for log blocks etc. */
+
+static void databuf_lo_after_scan(struct gfs2_jdesc *jd, int error, int pass)
+{
+	struct gfs2_sbd *sdp = jd->jd_inode->i_sbd;
+
+	if (error) {
+		gfs2_meta_sync(jd->jd_inode->i_gl, DIO_START | DIO_WAIT);
+		return;
+	}
+	if (pass != 1)
+		return;
+
+	/* data sync? */
+	gfs2_meta_sync(jd->jd_inode->i_gl, DIO_START | DIO_WAIT);
+
+	fs_info(sdp, "jid=%u: Replayed %u of %u data blocks\n",
+		jd->jd_jid, sdp->sd_replayed_blocks, sdp->sd_found_blocks);
+}
+
+static void databuf_lo_after_commit(struct gfs2_sbd *sdp, struct gfs2_ail *ai)
+{
+	struct list_head *head = &sdp->sd_log_le_databuf;
+	struct gfs2_bufdata *bd;
+
+	while (!list_empty(head)) {
+		bd = list_entry(head->next, struct gfs2_bufdata, bd_le.le_list);
+		list_del_init(&bd->bd_le.le_list);
+		sdp->sd_log_num_databuf--;
+		sdp->sd_log_num_jdata--;
+		gfs2_unpin(sdp, bd->bd_bh, ai);
+		brelse(bd->bd_bh);
+		kfree(bd);
+	}
 	gfs2_assert_warn(sdp, !sdp->sd_log_num_databuf);
+	gfs2_assert_warn(sdp, !sdp->sd_log_num_jdata);
 }
 
+
 struct gfs2_log_operations gfs2_glock_lops = {
 	.lo_add = glock_lo_add,
 	.lo_after_commit = glock_lo_after_commit,
@@ -519,7 +749,11 @@ struct gfs2_log_operations gfs2_rg_lops = {
 
 struct gfs2_log_operations gfs2_databuf_lops = {
 	.lo_add = databuf_lo_add,
+	.lo_incore_commit = buf_lo_incore_commit,
 	.lo_before_commit = databuf_lo_before_commit,
+	.lo_after_commit = databuf_lo_after_commit,
+	.lo_scan_elements = databuf_lo_scan_elements,
+	.lo_after_scan = databuf_lo_after_scan,
 	.lo_name = "databuf"
 };