md/raid1: tidy up new functions: process_checks and fix_sync_read_error.

These changes are mostly cosmetic:

1/ change mddev->raid_disks to conf->raid_disks because the later is
   technically safer, though in current practice it doesn't matter in
   this particular context.
2/ Rearrange two for / if loops to have an early 'continue' so the
   body of the 'if' doesn't need to be indented so much.

Signed-off-by: NeilBrown <neilb@suse.de>

1 files changed, 95 insertions, 89 deletions

diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c
index 7fd7a4d6f5c7..2b9e86ceaf2f 100644
--- a/drivers/md/raid1.c
+++ b/drivers/md/raid1.c
@@ -1203,6 +1203,7 @@ static int fix_sync_read_error(r1bio_t *r1_bio)
                 int d = r1_bio->read_disk;
                 int success = 0;
                 mdk_rdev_t *rdev;
+                int start;
 
                 if (s > (PAGE_SIZE>>9))
                         s = PAGE_SIZE >> 9;
@@ -1227,41 +1228,7 @@ static int fix_sync_read_error(r1bio_t *r1_bio)
                                 d = 0;
                 } while (!success && d != r1_bio->read_disk);
 
-                if (success) {
-                        int start = d;
-                        /* write it back and re-read */
-                        set_bit(R1BIO_Uptodate, &r1_bio->state);
-                        while (d != r1_bio->read_disk) {
-                                if (d == 0)
-                                        d = conf->raid_disks;
-                                d--;
-                                if (r1_bio->bios[d]->bi_end_io != end_sync_read)
-                                        continue;
-                                rdev = conf->mirrors[d].rdev;
-                                atomic_add(s, &rdev->corrected_errors);
-                                if (sync_page_io(rdev,
-                                                 sect,
-                                                 s<<9,
-                                                 bio->bi_io_vec[idx].bv_page,
-                                                 WRITE, false) == 0)
-                                        md_error(mddev, rdev);
-                        }
-                        d = start;
-                        while (d != r1_bio->read_disk) {
-                                if (d == 0)
-                                        d = conf->raid_disks;
-                                d--;
-                                if (r1_bio->bios[d]->bi_end_io != end_sync_read)
-                                        continue;
-                                rdev = conf->mirrors[d].rdev;
-                                if (sync_page_io(rdev,
-                                                 sect,
-                                                 s<<9,
-                                                 bio->bi_io_vec[idx].bv_page,
-                                                 READ, false) == 0)
-                                        md_error(mddev, rdev);
-                        }
-                } else {
+                if (!success) {
                         char b[BDEVNAME_SIZE];
                         /* Cannot read from anywhere, array is toast */
                         md_error(mddev, conf->mirrors[r1_bio->read_disk].rdev);
@@ -1274,10 +1241,47 @@ static int fix_sync_read_error(r1bio_t *r1_bio)
                         put_buf(r1_bio);
                         return 0;
                 }
+
+                start = d;
+                /* write it back and re-read */
+                while (d != r1_bio->read_disk) {
+                        if (d == 0)
+                                d = conf->raid_disks;
+                        d--;
+                        if (r1_bio->bios[d]->bi_end_io != end_sync_read)
+                                continue;
+                        rdev = conf->mirrors[d].rdev;
+                        if (sync_page_io(rdev,
+                                         sect,
+                                         s<<9,
+                                         bio->bi_io_vec[idx].bv_page,
+                                         WRITE, false) == 0) {
+                                r1_bio->bios[d]->bi_end_io = NULL;
+                                rdev_dec_pending(rdev, mddev);
+                                md_error(mddev, rdev);
+                        } else
+                                atomic_add(s, &rdev->corrected_errors);
+                }
+                d = start;
+                while (d != r1_bio->read_disk) {
+                        if (d == 0)
+                                d = conf->raid_disks;
+                        d--;
+                        if (r1_bio->bios[d]->bi_end_io != end_sync_read)
+                                continue;
+                        rdev = conf->mirrors[d].rdev;
+                        if (sync_page_io(rdev,
+                                         sect,
+                                         s<<9,
+                                         bio->bi_io_vec[idx].bv_page,
+                                         READ, false) == 0)
+                                md_error(mddev, rdev);
+                }
                 sectors -= s;
                 sect += s;
                 idx ++;
         }
+        set_bit(R1BIO_Uptodate, &r1_bio->state);
         return 1;
 }
 
@@ -1296,7 +1300,7 @@ static int process_checks(r1bio_t *r1_bio)
         int i;
 
         if (!test_bit(R1BIO_Uptodate, &r1_bio->state)) {
-                for (i=0; i<mddev->raid_disks; i++)
+                for (i=0; i < conf->raid_disks; i++)
                         if (r1_bio->bios[i]->bi_end_io == end_sync_read)
                                 md_error(mddev, conf->mirrors[i].rdev);
 
@@ -1304,7 +1308,7 @@ static int process_checks(r1bio_t *r1_bio)
                 put_buf(r1_bio);
                 return -1;
         }
-        for (primary=0; primary<mddev->raid_disks; primary++)
+        for (primary = 0; primary < conf->raid_disks; primary++)
                 if (r1_bio->bios[primary]->bi_end_io == end_sync_read &&
                     test_bit(BIO_UPTODATE, &r1_bio->bios[primary]->bi_flags)) {
                         r1_bio->bios[primary]->bi_end_io = NULL;
@@ -1312,61 +1316,63 @@ static int process_checks(r1bio_t *r1_bio)
                         break;
                 }
         r1_bio->read_disk = primary;
-        for (i=0; i<mddev->raid_disks; i++)
-                if (r1_bio->bios[i]->bi_end_io == end_sync_read) {
-                        int j;
-                        int vcnt = r1_bio->sectors >> (PAGE_SHIFT- 9);
-                        struct bio *pbio = r1_bio->bios[primary];
-                        struct bio *sbio = r1_bio->bios[i];
-
-                        if (test_bit(BIO_UPTODATE, &sbio->bi_flags)) {
-                                for (j = vcnt; j-- ; ) {
-                                        struct page *p, *s;
-                                        p = pbio->bi_io_vec[j].bv_page;
-                                        s = sbio->bi_io_vec[j].bv_page;
-                                        if (memcmp(page_address(p),
-                                                   page_address(s),
-                                                   PAGE_SIZE))
-                                                break;
-                                }
-                        } else
-                                j = 0;
-                        if (j >= 0)
-                                mddev->resync_mismatches += r1_bio->sectors;
-                        if (j < 0 || (test_bit(MD_RECOVERY_CHECK, &mddev->recovery)
-                                      && test_bit(BIO_UPTODATE, &sbio->bi_flags))) {
-                                sbio->bi_end_io = NULL;
-                                rdev_dec_pending(conf->mirrors[i].rdev, mddev);
-                        } else {
-                                /* fixup the bio for reuse */
-                                int size;
-                                sbio->bi_vcnt = vcnt;
-                                sbio->bi_size = r1_bio->sectors << 9;
-                                sbio->bi_idx = 0;
-                                sbio->bi_phys_segments = 0;
-                                sbio->bi_flags &= ~(BIO_POOL_MASK - 1);
-                                sbio->bi_flags |= 1 << BIO_UPTODATE;
-                                sbio->bi_next = NULL;
-                                sbio->bi_sector = r1_bio->sector +
-                                        conf->mirrors[i].rdev->data_offset;
-                                sbio->bi_bdev = conf->mirrors[i].rdev->bdev;
-                                size = sbio->bi_size;
-                                for (j = 0; j < vcnt ; j++) {
-                                        struct bio_vec *bi;
-                                        bi = &sbio->bi_io_vec[j];
-                                        bi->bv_offset = 0;
-                                        if (size > PAGE_SIZE)
-                                                bi->bv_len = PAGE_SIZE;
-                                        else
-                                                bi->bv_len = size;
-                                        size -= PAGE_SIZE;
-                                        memcpy(page_address(bi->bv_page),
-                                               page_address(pbio->bi_io_vec[j].bv_page),
-                                               PAGE_SIZE);
-                                }
+        for (i = 0; i < conf->raid_disks; i++) {
+                int j;
+                int vcnt = r1_bio->sectors >> (PAGE_SHIFT- 9);
+                struct bio *pbio = r1_bio->bios[primary];
+                struct bio *sbio = r1_bio->bios[i];
+                int size;
+
+                if (r1_bio->bios[i]->bi_end_io != end_sync_read)
+                        continue;
 
+                if (test_bit(BIO_UPTODATE, &sbio->bi_flags)) {
+                        for (j = vcnt; j-- ; ) {
+                                struct page *p, *s;
+                                p = pbio->bi_io_vec[j].bv_page;
+                                s = sbio->bi_io_vec[j].bv_page;
+                                if (memcmp(page_address(p),
+                                           page_address(s),
+                                           PAGE_SIZE))
+                                        break;
                         }
+                } else
+                        j = 0;
+                if (j >= 0)
+                        mddev->resync_mismatches += r1_bio->sectors;
+                if (j < 0 || (test_bit(MD_RECOVERY_CHECK, &mddev->recovery)
+                              && test_bit(BIO_UPTODATE, &sbio->bi_flags))) {
+                        /* No need to write to this device. */
+                        sbio->bi_end_io = NULL;
+                        rdev_dec_pending(conf->mirrors[i].rdev, mddev);
+                        continue;
                 }
+                /* fixup the bio for reuse */
+                sbio->bi_vcnt = vcnt;
+                sbio->bi_size = r1_bio->sectors << 9;
+                sbio->bi_idx = 0;
+                sbio->bi_phys_segments = 0;
+                sbio->bi_flags &= ~(BIO_POOL_MASK - 1);
+                sbio->bi_flags |= 1 << BIO_UPTODATE;
+                sbio->bi_next = NULL;
+                sbio->bi_sector = r1_bio->sector +
+                        conf->mirrors[i].rdev->data_offset;
+                sbio->bi_bdev = conf->mirrors[i].rdev->bdev;
+                size = sbio->bi_size;
+                for (j = 0; j < vcnt ; j++) {
+                        struct bio_vec *bi;
+                        bi = &sbio->bi_io_vec[j];
+                        bi->bv_offset = 0;
+                        if (size > PAGE_SIZE)
+                                bi->bv_len = PAGE_SIZE;
+                        else
+                                bi->bv_len = size;
+                        size -= PAGE_SIZE;
+                        memcpy(page_address(bi->bv_page),
+                               page_address(pbio->bi_io_vec[j].bv_page),
+                               PAGE_SIZE);
+                }
+        }
         return 0;
 }