[PATCH] Revert "gfs2: read journal in large chunks to locate the head"

From: Bob Peterson
Date: Wed Feb 13 2019 - 15:12:21 EST


This reverts commit 2a5f14f279f59143139bcd1606903f2f80a34241.

This patch causes xfstests generic/311 to fail. Reverting this for
now until we have a proper fix.

Signed-off-by: Abhi Das <adas@xxxxxxxxxx>
Signed-off-by: Bob Peterson <rpeterso@xxxxxxxxxx>
---
fs/gfs2/glops.c | 1 -
fs/gfs2/log.c | 4 +-
fs/gfs2/lops.c | 190 ++-------------------------------------------------
fs/gfs2/lops.h | 4 +-
fs/gfs2/ops_fstype.c | 1 -
fs/gfs2/recovery.c | 123 +++++++++++++++++++++++++++++++++
fs/gfs2/recovery.h | 2 +
fs/gfs2/super.c | 1 -
8 files changed, 134 insertions(+), 192 deletions(-)

diff --git a/fs/gfs2/glops.c b/fs/gfs2/glops.c
index f15b4c57c4bd..78510ab91835 100644
--- a/fs/gfs2/glops.c
+++ b/fs/gfs2/glops.c
@@ -28,7 +28,6 @@
#include "util.h"
#include "trans.h"
#include "dir.h"
-#include "lops.h"

struct workqueue_struct *gfs2_freeze_wq;

diff --git a/fs/gfs2/log.c b/fs/gfs2/log.c
index 5bfaf381921a..b8830fda51e8 100644
--- a/fs/gfs2/log.c
+++ b/fs/gfs2/log.c
@@ -733,7 +733,7 @@ void gfs2_write_log_header(struct gfs2_sbd *sdp, struct gfs2_jdesc *jd,
lh->lh_crc = cpu_to_be32(crc);

gfs2_log_write(sdp, page, sb->s_blocksize, 0, addr);
- gfs2_log_submit_bio(&sdp->sd_log_bio, REQ_OP_WRITE | op_flags);
+ gfs2_log_submit_bio(&sdp->sd_log_bio, REQ_OP_WRITE, op_flags);
log_flush_wait(sdp);
}

@@ -810,7 +810,7 @@ void gfs2_log_flush(struct gfs2_sbd *sdp, struct gfs2_glock *gl, u32 flags)

gfs2_ordered_write(sdp);
lops_before_commit(sdp, tr);
- gfs2_log_submit_bio(&sdp->sd_log_bio, REQ_OP_WRITE);
+ gfs2_log_submit_bio(&sdp->sd_log_bio, REQ_OP_WRITE, 0);

if (sdp->sd_log_head != sdp->sd_log_flush_head) {
log_flush_wait(sdp);
diff --git a/fs/gfs2/lops.c b/fs/gfs2/lops.c
index 94dcab655bc0..2295042bc625 100644
--- a/fs/gfs2/lops.c
+++ b/fs/gfs2/lops.c
@@ -17,9 +17,7 @@
#include <linux/bio.h>
#include <linux/fs.h>
#include <linux/list_sort.h>
-#include <linux/blkdev.h>

-#include "bmap.h"
#include "dir.h"
#include "gfs2.h"
#include "incore.h"
@@ -195,6 +193,7 @@ static void gfs2_end_log_write_bh(struct gfs2_sbd *sdp, struct bio_vec *bvec,
/**
* gfs2_end_log_write - end of i/o to the log
* @bio: The bio
+ * @error: Status of i/o request
*
* Each bio_vec contains either data from the pagecache or data
* relating to the log itself. Here we iterate over the bio_vec
@@ -231,19 +230,20 @@ static void gfs2_end_log_write(struct bio *bio)
/**
* gfs2_log_submit_bio - Submit any pending log bio
* @biop: Address of the bio pointer
- * @opf: REQ_OP | op_flags
+ * @op: REQ_OP
+ * @op_flags: req_flag_bits
*
* Submit any pending part-built or full bio to the block device. If
* there is no pending bio, then this is a no-op.
*/

-void gfs2_log_submit_bio(struct bio **biop, int opf)
+void gfs2_log_submit_bio(struct bio **biop, int op, int op_flags)
{
struct bio *bio = *biop;
if (bio) {
struct gfs2_sbd *sdp = bio->bi_private;
atomic_inc(&sdp->sd_log_in_flight);
- bio->bi_opf = opf;
+ bio_set_op_attrs(bio, op, op_flags);
submit_bio(bio);
*biop = NULL;
}
@@ -304,7 +304,7 @@ static struct bio *gfs2_log_get_bio(struct gfs2_sbd *sdp, u64 blkno,
nblk >>= sdp->sd_fsb2bb_shift;
if (blkno == nblk && !flush)
return bio;
- gfs2_log_submit_bio(biop, op);
+ gfs2_log_submit_bio(biop, op, 0);
}

*biop = gfs2_log_alloc_bio(sdp, blkno, end_io);
@@ -375,184 +375,6 @@ void gfs2_log_write_page(struct gfs2_sbd *sdp, struct page *page)
gfs2_log_bmap(sdp));
}

-/**
- * gfs2_end_log_read - end I/O callback for reads from the log
- * @bio: The bio
- *
- * Simply unlock the pages in the bio. The main thread will wait on them and
- * process them in order as necessary.
- */
-
-static void gfs2_end_log_read(struct bio *bio)
-{
- struct page *page;
- struct bio_vec *bvec;
- int i;
-
- bio_for_each_segment_all(bvec, bio, i) {
- page = bvec->bv_page;
- if (bio->bi_status) {
- int err = blk_status_to_errno(bio->bi_status);
-
- SetPageError(page);
- mapping_set_error(page->mapping, err);
- }
- unlock_page(page);
- }
-
- bio_put(bio);
-}
-
-/**
- * gfs2_jhead_pg_srch - Look for the journal head in a given page.
- * @jd: The journal descriptor
- * @page: The page to look in
- *
- * Returns: 1 if found, 0 otherwise.
- */
-
-static bool gfs2_jhead_pg_srch(struct gfs2_jdesc *jd,
- struct gfs2_log_header_host *head,
- struct page *page)
-{
- struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode);
- struct gfs2_log_header_host uninitialized_var(lh);
- void *kaddr = kmap_atomic(page);
- unsigned int offset;
- bool ret = false;
-
- for (offset = 0; offset < PAGE_SIZE; offset += sdp->sd_sb.sb_bsize) {
- if (!__get_log_header(sdp, kaddr + offset, 0, &lh)) {
- if (lh.lh_sequence > head->lh_sequence)
- *head = lh;
- else {
- ret = true;
- break;
- }
- }
- }
- kunmap_atomic(kaddr);
- return ret;
-}
-
-/**
- * gfs2_jhead_process_page - Search/cleanup a page
- * @jd: The journal descriptor
- * @index: Index of the page to look into
- * @done: If set, perform only cleanup, else search and set if found.
- *
- * Find the page with 'index' in the journal's mapping. Search the page for
- * the journal head if requested (cleanup == false). Release refs on the
- * page so the page cache can reclaim it (put_page() twice). We grabbed a
- * reference on this page two times, first when we did a find_or_create_page()
- * to obtain the page to add it to the bio and second when we do a
- * find_get_page() here to get the page to wait on while I/O on it is being
- * completed.
- * This function is also used to free up a page we might've grabbed but not
- * used. Maybe we added it to a bio, but not submitted it for I/O. Or we
- * submitted the I/O, but we already found the jhead so we only need to drop
- * our references to the page.
- */
-
-static void gfs2_jhead_process_page(struct gfs2_jdesc *jd, unsigned long index,
- struct gfs2_log_header_host *head,
- bool *done)
-{
- struct page *page;
-
- page = find_get_page(jd->jd_inode->i_mapping, index);
- wait_on_page_locked(page);
-
- if (PageError(page))
- *done = true;
-
- if (!*done)
- *done = gfs2_jhead_pg_srch(jd, head, page);
-
- put_page(page); /* Once for find_get_page */
- put_page(page); /* Once more for find_or_create_page */
-}
-
-/**
- * gfs2_find_jhead - find the head of a log
- * @jd: The journal descriptor
- * @head: The log descriptor for the head of the log is returned here
- *
- * Do a search of a journal by reading it in large chunks using bios and find
- * the valid log entry with the highest sequence number. (i.e. the log head)
- *
- * Returns: 0 on success, errno otherwise
- */
-
-int gfs2_find_jhead(struct gfs2_jdesc *jd, struct gfs2_log_header_host *head)
-{
- struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode);
- struct address_space *mapping = jd->jd_inode->i_mapping;
- struct gfs2_journal_extent *je;
- u32 block, read_idx = 0, submit_idx = 0, index = 0;
- int shift = PAGE_SHIFT - sdp->sd_sb.sb_bsize_shift;
- int blocks_per_page = 1 << shift, sz, ret = 0;
- struct bio *bio = NULL;
- struct page *page;
- bool done = false;
- errseq_t since;
-
- memset(head, 0, sizeof(*head));
- if (list_empty(&jd->extent_list))
- gfs2_map_journal_extents(sdp, jd);
-
- since = filemap_sample_wb_err(mapping);
- list_for_each_entry(je, &jd->extent_list, list) {
- for (block = 0; block < je->blocks; block += blocks_per_page) {
- index = (je->lblock + block) >> shift;
-
- page = find_or_create_page(mapping, index, GFP_NOFS);
- if (!page) {
- ret = -ENOMEM;
- done = true;
- goto out;
- }
-
- if (bio) {
- sz = bio_add_page(bio, page, PAGE_SIZE, 0);
- if (sz == PAGE_SIZE)
- goto page_added;
- submit_idx = index;
- submit_bio(bio);
- bio = NULL;
- }
-
- bio = gfs2_log_alloc_bio(sdp,
- je->dblock + (index << shift),
- gfs2_end_log_read);
- bio->bi_opf = REQ_OP_READ;
- sz = bio_add_page(bio, page, PAGE_SIZE, 0);
- gfs2_assert_warn(sdp, sz == PAGE_SIZE);
-
-page_added:
- if (submit_idx <= read_idx + BIO_MAX_PAGES) {
- /* Keep at least one bio in flight */
- continue;
- }
-
- gfs2_jhead_process_page(jd, read_idx++, head, &done);
- if (done)
- goto out; /* found */
- }
- }
-
-out:
- if (bio)
- submit_bio(bio);
- while (read_idx <= index)
- gfs2_jhead_process_page(jd, read_idx++, head, &done);
-
- if (!ret)
- ret = filemap_check_wb_err(mapping, since);
-
- return ret;
-}
-
static struct page *gfs2_get_log_desc(struct gfs2_sbd *sdp, u32 ld_type,
u32 ld_length, u32 ld_data1)
{
diff --git a/fs/gfs2/lops.h b/fs/gfs2/lops.h
index 331160fc568b..711c4d89c063 100644
--- a/fs/gfs2/lops.h
+++ b/fs/gfs2/lops.h
@@ -30,10 +30,8 @@ extern u64 gfs2_log_bmap(struct gfs2_sbd *sdp);
extern void gfs2_log_write(struct gfs2_sbd *sdp, struct page *page,
unsigned size, unsigned offset, u64 blkno);
extern void gfs2_log_write_page(struct gfs2_sbd *sdp, struct page *page);
-extern void gfs2_log_submit_bio(struct bio **biop, int opf);
+extern void gfs2_log_submit_bio(struct bio **biop, int op, int op_flags);
extern void gfs2_pin(struct gfs2_sbd *sdp, struct buffer_head *bh);
-extern int gfs2_find_jhead(struct gfs2_jdesc *jd,
- struct gfs2_log_header_host *head);

static inline unsigned int buf_limit(struct gfs2_sbd *sdp)
{
diff --git a/fs/gfs2/ops_fstype.c b/fs/gfs2/ops_fstype.c
index 1179763f6370..b041cb8ae383 100644
--- a/fs/gfs2/ops_fstype.c
+++ b/fs/gfs2/ops_fstype.c
@@ -41,7 +41,6 @@
#include "dir.h"
#include "meta_io.h"
#include "trace_gfs2.h"
-#include "lops.h"

#define DO 0
#define UNDO 1
diff --git a/fs/gfs2/recovery.c b/fs/gfs2/recovery.c
index 7389e445a7a7..2dac43065382 100644
--- a/fs/gfs2/recovery.c
+++ b/fs/gfs2/recovery.c
@@ -181,6 +181,129 @@ static int get_log_header(struct gfs2_jdesc *jd, unsigned int blk,
return error;
}

+/**
+ * find_good_lh - find a good log header
+ * @jd: the journal
+ * @blk: the segment to start searching from
+ * @lh: the log header to fill in
+ * @forward: if true search forward in the log, else search backward
+ *
+ * Call get_log_header() to get a log header for a segment, but if the
+ * segment is bad, either scan forward or backward until we find a good one.
+ *
+ * Returns: errno
+ */
+
+static int find_good_lh(struct gfs2_jdesc *jd, unsigned int *blk,
+ struct gfs2_log_header_host *head)
+{
+ unsigned int orig_blk = *blk;
+ int error;
+
+ for (;;) {
+ error = get_log_header(jd, *blk, head);
+ if (error <= 0)
+ return error;
+
+ if (++*blk == jd->jd_blocks)
+ *blk = 0;
+
+ if (*blk == orig_blk) {
+ gfs2_consist_inode(GFS2_I(jd->jd_inode));
+ return -EIO;
+ }
+ }
+}
+
+/**
+ * jhead_scan - make sure we've found the head of the log
+ * @jd: the journal
+ * @head: this is filled in with the log descriptor of the head
+ *
+ * At this point, seg and lh should be either the head of the log or just
+ * before. Scan forward until we find the head.
+ *
+ * Returns: errno
+ */
+
+static int jhead_scan(struct gfs2_jdesc *jd, struct gfs2_log_header_host *head)
+{
+ unsigned int blk = head->lh_blkno;
+ struct gfs2_log_header_host lh;
+ int error;
+
+ for (;;) {
+ if (++blk == jd->jd_blocks)
+ blk = 0;
+
+ error = get_log_header(jd, blk, &lh);
+ if (error < 0)
+ return error;
+ if (error == 1)
+ continue;
+
+ if (lh.lh_sequence == head->lh_sequence) {
+ gfs2_consist_inode(GFS2_I(jd->jd_inode));
+ return -EIO;
+ }
+ if (lh.lh_sequence < head->lh_sequence)
+ break;
+
+ *head = lh;
+ }
+
+ return 0;
+}
+
+/**
+ * gfs2_find_jhead - find the head of a log
+ * @jd: the journal
+ * @head: the log descriptor for the head of the log is returned here
+ *
+ * Do a binary search of a journal and find the valid log entry with the
+ * highest sequence number. (i.e. the log head)
+ *
+ * Returns: errno
+ */
+
+int gfs2_find_jhead(struct gfs2_jdesc *jd, struct gfs2_log_header_host *head)
+{
+ struct gfs2_log_header_host lh_1, lh_m;
+ u32 blk_1, blk_2, blk_m;
+ int error;
+
+ blk_1 = 0;
+ blk_2 = jd->jd_blocks - 1;
+
+ for (;;) {
+ blk_m = (blk_1 + blk_2) / 2;
+
+ error = find_good_lh(jd, &blk_1, &lh_1);
+ if (error)
+ return error;
+
+ error = find_good_lh(jd, &blk_m, &lh_m);
+ if (error)
+ return error;
+
+ if (blk_1 == blk_m || blk_m == blk_2)
+ break;
+
+ if (lh_1.lh_sequence <= lh_m.lh_sequence)
+ blk_1 = blk_m;
+ else
+ blk_2 = blk_m;
+ }
+
+ error = jhead_scan(jd, &lh_1);
+ if (error)
+ return error;
+
+ *head = lh_1;
+
+ return error;
+}
+
/**
* foreach_descriptor - go through the active part of the log
* @jd: the journal
diff --git a/fs/gfs2/recovery.h b/fs/gfs2/recovery.h
index 99575ab81202..11d81248be85 100644
--- a/fs/gfs2/recovery.h
+++ b/fs/gfs2/recovery.h
@@ -27,6 +27,8 @@ extern int gfs2_revoke_add(struct gfs2_jdesc *jd, u64 blkno, unsigned int where)
extern int gfs2_revoke_check(struct gfs2_jdesc *jd, u64 blkno, unsigned int where);
extern void gfs2_revoke_clean(struct gfs2_jdesc *jd);

+extern int gfs2_find_jhead(struct gfs2_jdesc *jd,
+ struct gfs2_log_header_host *head);
extern int gfs2_recover_journal(struct gfs2_jdesc *gfs2_jd, bool wait);
extern void gfs2_recover_func(struct work_struct *work);
extern int __get_log_header(struct gfs2_sbd *sdp,
diff --git a/fs/gfs2/super.c b/fs/gfs2/super.c
index d4b11c903971..ca71163ff7cf 100644
--- a/fs/gfs2/super.c
+++ b/fs/gfs2/super.c
@@ -45,7 +45,6 @@
#include "util.h"
#include "sys.h"
#include "xattr.h"
-#include "lops.h"

#define args_neq(a1, a2, x) ((a1)->ar_##x != (a2)->ar_##x)