bcachefs: Improve btree node read error path

This ensures that failure to read a btree node error is treated as a
topology error, and returns the correct error so that the topology
repair pass will be run.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

diff --git a/fs/bcachefs/btree_io.c b/fs/bcachefs/btree_io.c
index 700ce14baa2440caaaa905bac285f7fe19f279bd..dfa45cf4021f7000c2e7d5659bfceec1c32d5305 100644 (file)
--- a/fs/bcachefs/btree_io.c
+++ b/fs/bcachefs/btree_io.c
@@ -536,10 +536,23 @@ static void btree_err_msg(struct printbuf *out, struct bch_fs *c,
 }
 
 enum btree_err_type {
+       /*
+        * We can repair this locally, and we're after the checksum check so
+        * there's no need to try another replica:
+        */
        BTREE_ERR_FIXABLE,
+       /*
+        * We can repair this if we have to, but we should try reading another
+        * replica if we can:
+        */
        BTREE_ERR_WANT_RETRY,
+       /*
+        * Read another replica if we have one, otherwise consider the whole
+        * node bad:
+        */
        BTREE_ERR_MUST_RETRY,
-       BTREE_ERR_FATAL,
+       BTREE_ERR_BAD_NODE,
+       BTREE_ERR_INCOMPATIBLE,
 };
 
 enum btree_validate_ret {
@@ -565,36 +578,40 @@ static int __btree_err(enum btree_err_type type,
        prt_vprintf(&out, fmt, args);
        va_end(args);
 
-       if (write == READ &&
-           type == BTREE_ERR_FIXABLE &&
-           !test_bit(BCH_FS_FSCK_DONE, &c->flags)) {
-               mustfix_fsck_err(c, "%s", out.buf);
-               goto out;
-       }
-
-       bch2_print_string_as_lines(KERN_ERR, out.buf);
-
        if (write == WRITE) {
+               bch2_print_string_as_lines(KERN_ERR, out.buf);
                ret = c->opts.errors == BCH_ON_ERROR_continue
                        ? 0
                        : -BCH_ERR_fsck_errors_not_fixed;
                goto out;
        }
 
+       if (!have_retry && type == BTREE_ERR_WANT_RETRY)
+               type = BTREE_ERR_FIXABLE;
+       if (!have_retry && type == BTREE_ERR_MUST_RETRY)
+               type = BTREE_ERR_BAD_NODE;
+
        switch (type) {
        case BTREE_ERR_FIXABLE:
-               ret = -BCH_ERR_fsck_errors_not_fixed;
+               mustfix_fsck_err(c, "%s", out.buf);
+               ret = -BCH_ERR_fsck_fix;
                break;
        case BTREE_ERR_WANT_RETRY:
-               if (have_retry)
-                       ret = BTREE_RETRY_READ;
-               break;
        case BTREE_ERR_MUST_RETRY:
+               bch2_print_string_as_lines(KERN_ERR, out.buf);
                ret = BTREE_RETRY_READ;
                break;
-       case BTREE_ERR_FATAL:
+       case BTREE_ERR_BAD_NODE:
+               bch2_print_string_as_lines(KERN_ERR, out.buf);
+               bch2_topology_error(c);
+               ret = -BCH_ERR_need_topology_repair;
+               break;
+       case BTREE_ERR_INCOMPATIBLE:
+               bch2_print_string_as_lines(KERN_ERR, out.buf);
                ret = -BCH_ERR_fsck_errors_not_fixed;
                break;
+       default:
+               BUG();
        }
 out:
 fsck_err:
@@ -679,7 +696,7 @@ static int validate_bset(struct bch_fs *c, struct bch_dev *ca,
        btree_err_on((version != BCH_BSET_VERSION_OLD &&
                      version < bcachefs_metadata_version_min) ||
                     version >= bcachefs_metadata_version_max,
-                    BTREE_ERR_FATAL, c, ca, b, i,
+                    BTREE_ERR_INCOMPATIBLE, c, ca, b, i,
                     "unsupported bset version");
 
        if (btree_err_on(version < c->sb.version_min,
@@ -703,7 +720,7 @@ static int validate_bset(struct bch_fs *c, struct bch_dev *ca,
        }
 
        btree_err_on(BSET_SEPARATE_WHITEOUTS(i),
-                    BTREE_ERR_FATAL, c, ca, b, i,
+                    BTREE_ERR_INCOMPATIBLE, c, ca, b, i,
                     "BSET_SEPARATE_WHITEOUTS no longer supported");
 
        if (btree_err_on(offset + sectors > btree_sectors(c),
@@ -780,7 +797,7 @@ static int validate_bset(struct bch_fs *c, struct bch_dev *ca,
 
                err = bch2_bkey_format_validate(&bn->format);
                btree_err_on(err,
-                            BTREE_ERR_FATAL, c, ca, b, i,
+                            BTREE_ERR_BAD_NODE, c, ca, b, i,
                             "invalid bkey format: %s", err);
 
                compat_bformat(b->c.level, b->c.btree_id, version,
@@ -969,7 +986,7 @@ int bch2_btree_node_read_done(struct bch_fs *c, struct bch_dev *ca,
 
                        btree_err_on(btree_node_type_is_extents(btree_node_type(b)) &&
                                     !BTREE_NODE_NEW_EXTENT_OVERWRITE(b->data),
-                                    BTREE_ERR_FATAL, c, NULL, b, NULL,
+                                    BTREE_ERR_INCOMPATIBLE, c, NULL, b, NULL,
                                     "btree node does not have NEW_EXTENT_OVERWRITE set");
 
                        sectors = vstruct_sectors(b->data, c->block_bits);
@@ -1151,12 +1168,10 @@ out:
        printbuf_exit(&buf);
        return retry_read;
 fsck_err:
-       if (ret == BTREE_RETRY_READ) {
+       if (ret == BTREE_RETRY_READ)
                retry_read = 1;
-       } else {
-               bch2_inconsistent_error(c);
+       else
                set_btree_node_read_error(b);
-       }
        goto out;
 }
 

diff --git a/fs/bcachefs/error.c b/fs/bcachefs/error.c
index 3e49d72d65b5e8db791cfa6254529e9217fce4e6..c2882c599896cc694c9e0180bf4abf4e90f05e0a 100644 (file)
--- a/fs/bcachefs/error.c
+++ b/fs/bcachefs/error.c
@@ -27,8 +27,11 @@ bool bch2_inconsistent_error(struct bch_fs *c)
 
 void bch2_topology_error(struct bch_fs *c)
 {
+       if (!test_bit(BCH_FS_TOPOLOGY_REPAIR_DONE, &c->flags))
+               return;
+
        set_bit(BCH_FS_TOPOLOGY_ERROR, &c->flags);
-       if (test_bit(BCH_FS_INITIAL_GC_DONE, &c->flags))
+       if (test_bit(BCH_FS_FSCK_DONE, &c->flags))
                bch2_inconsistent_error(c);
 }