[GFS2] Clean up journaled data writing
This patch cleans up the code for writing journaled data into the log.
It also removes the need to allocate a small "tag" structure for each
block written into the log. Instead we just keep count of the outstanding
I/O so that we can be sure that its all been written at the correct time.
Another result of this patch is that a number of ll_rw_block() calls
have become submit_bh() calls, closing some races at the same time.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
diff --git a/fs/gfs2/lops.c b/fs/gfs2/lops.c
index 342c10e..6c27cea 100644
--- a/fs/gfs2/lops.c
+++ b/fs/gfs2/lops.c
@@ -91,6 +91,39 @@
unlock_buffer(bh);
}
+
+static inline struct gfs2_log_descriptor *bh_log_desc(struct buffer_head *bh)
+{
+ return (struct gfs2_log_descriptor *)bh->b_data;
+}
+
+static inline __be64 *bh_log_ptr(struct buffer_head *bh)
+{
+ struct gfs2_log_descriptor *ld = bh_log_desc(bh);
+ return (__force __be64 *)(ld + 1);
+}
+
+static inline __be64 *bh_ptr_end(struct buffer_head *bh)
+{
+ return (__force __be64 *)(bh->b_data + bh->b_size);
+}
+
+
+static struct buffer_head *gfs2_get_log_desc(struct gfs2_sbd *sdp, u32 ld_type)
+{
+ struct buffer_head *bh = gfs2_log_get_buf(sdp);
+ struct gfs2_log_descriptor *ld = bh_log_desc(bh);
+ ld->ld_header.mh_magic = cpu_to_be32(GFS2_MAGIC);
+ ld->ld_header.mh_type = cpu_to_be32(GFS2_METATYPE_LD);
+ ld->ld_header.mh_format = cpu_to_be32(GFS2_FORMAT_LD);
+ ld->ld_type = cpu_to_be32(ld_type);
+ ld->ld_length = 0;
+ ld->ld_data1 = 0;
+ ld->ld_data2 = 0;
+ memset(ld->ld_reserved, 0, sizeof(ld->ld_reserved));
+ return bh;
+}
+
static void __glock_lo_add(struct gfs2_sbd *sdp, struct gfs2_log_element *le)
{
struct gfs2_glock *gl;
@@ -181,7 +214,6 @@
struct gfs2_log_descriptor *ld;
struct gfs2_bufdata *bd1 = NULL, *bd2;
unsigned int total;
- unsigned int offset = BUF_OFFSET;
unsigned int limit;
unsigned int num;
unsigned n;
@@ -198,18 +230,12 @@
if (total > limit)
num = limit;
gfs2_log_unlock(sdp);
- bh = gfs2_log_get_buf(sdp);
+ bh = gfs2_get_log_desc(sdp, GFS2_LOG_DESC_METADATA);
gfs2_log_lock(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_be32(GFS2_METATYPE_LD);
- ld->ld_header.mh_format = cpu_to_be32(GFS2_FORMAT_LD);
- ld->ld_type = cpu_to_be32(GFS2_LOG_DESC_METADATA);
+ ld = bh_log_desc(bh);
+ ptr = bh_log_ptr(bh);
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));
n = 0;
list_for_each_entry_continue(bd1, &sdp->sd_log_le_buf,
@@ -220,17 +246,17 @@
}
gfs2_log_unlock(sdp);
- set_buffer_dirty(bh);
- ll_rw_block(WRITE, 1, &bh);
+ submit_bh(WRITE, bh);
gfs2_log_lock(sdp);
n = 0;
list_for_each_entry_continue(bd2, &sdp->sd_log_le_buf,
bd_le.le_list) {
+ get_bh(bd2->bd_bh);
gfs2_log_unlock(sdp);
+ lock_buffer(bd2->bd_bh);
bh = gfs2_log_fake_buf(sdp, bd2->bd_bh);
- set_buffer_dirty(bh);
- ll_rw_block(WRITE, 1, &bh);
+ submit_bh(WRITE, bh);
gfs2_log_lock(sdp);
if (++n >= num)
break;
@@ -359,17 +385,11 @@
if (!sdp->sd_log_num_revoke)
return;
- bh = gfs2_log_get_buf(sdp);
- ld = (struct gfs2_log_descriptor *)bh->b_data;
- ld->ld_header.mh_magic = cpu_to_be32(GFS2_MAGIC);
- ld->ld_header.mh_type = cpu_to_be32(GFS2_METATYPE_LD);
- ld->ld_header.mh_format = cpu_to_be32(GFS2_FORMAT_LD);
- ld->ld_type = cpu_to_be32(GFS2_LOG_DESC_REVOKE);
+ bh = gfs2_get_log_desc(sdp, GFS2_LOG_DESC_REVOKE);
+ ld = bh_log_desc(bh);
ld->ld_length = cpu_to_be32(gfs2_struct2blk(sdp, sdp->sd_log_num_revoke,
sizeof(u64)));
ld->ld_data1 = cpu_to_be32(sdp->sd_log_num_revoke);
- ld->ld_data2 = cpu_to_be32(0);
- memset(ld->ld_reserved, 0, sizeof(ld->ld_reserved));
offset = sizeof(struct gfs2_log_descriptor);
while (!list_empty(head)) {
@@ -378,8 +398,7 @@
sdp->sd_log_num_revoke--;
if (offset + sizeof(u64) > sdp->sd_sb.sb_bsize) {
- set_buffer_dirty(bh);
- ll_rw_block(WRITE, 1, &bh);
+ submit_bh(WRITE, bh);
bh = gfs2_log_get_buf(sdp);
mh = (struct gfs2_meta_header *)bh->b_data;
@@ -396,8 +415,7 @@
}
gfs2_assert_withdraw(sdp, !sdp->sd_log_num_revoke);
- set_buffer_dirty(bh);
- ll_rw_block(WRITE, 1, &bh);
+ submit_bh(WRITE, bh);
}
static void revoke_lo_before_scan(struct gfs2_jdesc *jd,
@@ -562,20 +580,70 @@
unlock_buffer(bd->bd_bh);
}
-static int gfs2_check_magic(struct buffer_head *bh)
+static void 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);
+ clear_buffer_escaped(bh);
+ kaddr = kmap_atomic(bh->b_page, KM_USER0);
ptr = kaddr + bh_offset(bh);
if (*ptr == cpu_to_be32(GFS2_MAGIC))
- rv = 1;
+ set_buffer_escaped(bh);
kunmap_atomic(kaddr, KM_USER0);
+}
- return rv;
+static void gfs2_write_blocks(struct gfs2_sbd *sdp, struct buffer_head *bh,
+ struct list_head *list, struct list_head *done,
+ unsigned int n)
+{
+ struct buffer_head *bh1;
+ struct gfs2_log_descriptor *ld;
+ struct gfs2_bufdata *bd;
+ __be64 *ptr;
+
+ if (!bh)
+ return;
+
+ ld = bh_log_desc(bh);
+ ld->ld_length = cpu_to_be32(n + 1);
+ ld->ld_data1 = cpu_to_be32(n);
+
+ ptr = bh_log_ptr(bh);
+
+ get_bh(bh);
+ submit_bh(WRITE, bh);
+ gfs2_log_lock(sdp);
+ while(!list_empty(list)) {
+ bd = list_entry(list->next, struct gfs2_bufdata, bd_le.le_list);
+ list_move_tail(&bd->bd_le.le_list, done);
+ get_bh(bd->bd_bh);
+ while (be64_to_cpu(*ptr) != bd->bd_bh->b_blocknr) {
+ gfs2_log_incr_head(sdp);
+ ptr += 2;
+ }
+ gfs2_log_unlock(sdp);
+ lock_buffer(bd->bd_bh);
+ if (buffer_escaped(bd->bd_bh)) {
+ void *kaddr;
+ bh1 = gfs2_log_get_buf(sdp);
+ kaddr = kmap_atomic(bd->bd_bh->b_page, KM_USER0);
+ memcpy(bh1->b_data, kaddr + bh_offset(bd->bd_bh),
+ bh1->b_size);
+ kunmap_atomic(kaddr, KM_USER0);
+ *(__be32 *)bh1->b_data = 0;
+ clear_buffer_escaped(bd->bd_bh);
+ unlock_buffer(bd->bd_bh);
+ brelse(bd->bd_bh);
+ } else {
+ bh1 = gfs2_log_fake_buf(sdp, bd->bd_bh);
+ }
+ submit_bh(WRITE, bh1);
+ gfs2_log_lock(sdp);
+ ptr += 2;
+ }
+ gfs2_log_unlock(sdp);
+ brelse(bh);
}
/**
@@ -585,95 +653,37 @@
static void databuf_lo_before_commit(struct gfs2_sbd *sdp)
{
- struct gfs2_bufdata *bd1 = NULL, *bd2;
- struct buffer_head *bh = NULL,*bh1 = NULL;
- struct gfs2_log_descriptor *ld;
- unsigned int limit;
- unsigned int total;
- unsigned int num, n;
- __be64 *ptr = NULL;
- int magic;
-
-
- limit = databuf_limit(sdp);
+ struct gfs2_bufdata *bd = NULL;
+ struct buffer_head *bh = NULL;
+ unsigned int n = 0;
+ __be64 *ptr = NULL, *end = NULL;
+ LIST_HEAD(processed);
+ LIST_HEAD(in_progress);
gfs2_log_lock(sdp);
- total = sdp->sd_log_num_databuf;
- bd2 = bd1 = list_prepare_entry(bd1, &sdp->sd_log_le_databuf,
- bd_le.le_list);
- while(total) {
- num = total;
- if (num > limit)
- num = limit;
-
- gfs2_log_unlock(sdp);
- bh = gfs2_log_get_buf(sdp);
- gfs2_log_lock(sdp);
-
- ld = (struct gfs2_log_descriptor *)bh->b_data;
- ptr = (__be64 *)(bh->b_data + DATABUF_OFFSET);
- ld->ld_header.mh_magic = cpu_to_be32(GFS2_MAGIC);
- ld->ld_header.mh_type = cpu_to_be32(GFS2_METATYPE_LD);
- ld->ld_header.mh_format = cpu_to_be32(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));
-
- n = 0;
- list_for_each_entry_continue(bd1, &sdp->sd_log_le_databuf,
- bd_le.le_list) {
- bh1 = bd1->bd_bh;
-
- magic = gfs2_check_magic(bh1);
- *ptr++ = cpu_to_be64(bh1->b_blocknr);
- *ptr++ = cpu_to_be64((__u64)magic);
- clear_buffer_escaped(bh1);
- if (unlikely(magic != 0))
- set_buffer_escaped(bh1);
- if (++n >= num)
- break;
- }
- gfs2_log_unlock(sdp);
- if (bh) {
- set_buffer_dirty(bh);
- ll_rw_block(WRITE, 1, &bh);
- bh = NULL;
- ptr = NULL;
- }
- n = 0;
- gfs2_log_lock(sdp);
- 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 */
+ while (!list_empty(&sdp->sd_log_le_databuf)) {
+ if (ptr == end) {
gfs2_log_unlock(sdp);
- 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(kaddr, KM_USER0);
- *(__be32 *)bh->b_data = 0;
- } else {
- bh = gfs2_log_fake_buf(sdp, bd2->bd_bh);
- }
- set_buffer_dirty(bh);
- ll_rw_block(WRITE, 1, &bh);
+ gfs2_write_blocks(sdp, bh, &in_progress, &processed, n);
+ n = 0;
+ bh = gfs2_get_log_desc(sdp, GFS2_LOG_DESC_JDATA);
+ ptr = bh_log_ptr(bh);
+ end = bh_ptr_end(bh) - 1;
gfs2_log_lock(sdp);
- if (++n >= num)
- break;
+ continue;
}
- bh = NULL;
- BUG_ON(total < num);
- total -= num;
+ bd = list_entry(sdp->sd_log_le_databuf.next, struct gfs2_bufdata, bd_le.le_list);
+ list_move_tail(&bd->bd_le.le_list, &in_progress);
+ gfs2_check_magic(bd->bd_bh);
+ *ptr++ = cpu_to_be64(bd->bd_bh->b_blocknr);
+ *ptr++ = cpu_to_be64(buffer_escaped(bh) ? 1 : 0);
+ n++;
}
gfs2_log_unlock(sdp);
+ gfs2_write_blocks(sdp, bh, &in_progress, &processed, n);
+ gfs2_log_lock(sdp);
+ list_splice(&processed, &sdp->sd_log_le_databuf);
+ gfs2_log_unlock(sdp);
}
static int databuf_lo_scan_elements(struct gfs2_jdesc *jd, unsigned int start,
@@ -807,10 +817,10 @@
const struct gfs2_log_operations *gfs2_log_ops[] = {
&gfs2_glock_lops,
- &gfs2_buf_lops,
- &gfs2_revoke_lops,
- &gfs2_rg_lops,
&gfs2_databuf_lops,
+ &gfs2_buf_lops,
+ &gfs2_rg_lops,
+ &gfs2_revoke_lops,
NULL,
};