summaryrefslogtreecommitdiffstats
path: root/fs/bcachefs/sb-downgrade.c
diff options
context:
space:
mode:
Diffstat (limited to 'fs/bcachefs/sb-downgrade.c')
-rw-r--r--fs/bcachefs/sb-downgrade.c188
1 files changed, 188 insertions, 0 deletions
diff --git a/fs/bcachefs/sb-downgrade.c b/fs/bcachefs/sb-downgrade.c
new file mode 100644
index 0000000000..4919237bbe
--- /dev/null
+++ b/fs/bcachefs/sb-downgrade.c
@@ -0,0 +1,188 @@
+// SPDX-License-Identifier: GPL-2.0
+
+/*
+ * Superblock section that contains a list of recovery passes to run when
+ * downgrading past a given version
+ */
+
+#include "bcachefs.h"
+#include "darray.h"
+#include "recovery.h"
+#include "sb-downgrade.h"
+#include "sb-errors.h"
+#include "super-io.h"
+
+/*
+ * Downgrade table:
+ * When dowgrading past certain versions, we need to run certain recovery passes
+ * and fix certain errors:
+ *
+ * x(version, recovery_passes, errors...)
+ */
+
+#define DOWNGRADE_TABLE()
+
+struct downgrade_entry {
+ u64 recovery_passes;
+ u16 version;
+ u16 nr_errors;
+ const u16 *errors;
+};
+
+#define x(ver, passes, ...) static const u16 ver_##errors[] = { __VA_ARGS__ };
+DOWNGRADE_TABLE()
+#undef x
+
+static const struct downgrade_entry downgrade_table[] = {
+#define x(ver, passes, ...) { \
+ .recovery_passes = passes, \
+ .version = bcachefs_metadata_version_##ver,\
+ .nr_errors = ARRAY_SIZE(ver_##errors), \
+ .errors = ver_##errors, \
+},
+DOWNGRADE_TABLE()
+#undef x
+};
+
+static inline const struct bch_sb_field_downgrade_entry *
+downgrade_entry_next_c(const struct bch_sb_field_downgrade_entry *e)
+{
+ return (void *) &e->errors[le16_to_cpu(e->nr_errors)];
+}
+
+#define for_each_downgrade_entry(_d, _i) \
+ for (const struct bch_sb_field_downgrade_entry *_i = (_d)->entries; \
+ (void *) _i < vstruct_end(&(_d)->field) && \
+ (void *) &_i->errors[0] < vstruct_end(&(_d)->field); \
+ _i = downgrade_entry_next_c(_i))
+
+static int bch2_sb_downgrade_validate(struct bch_sb *sb, struct bch_sb_field *f,
+ struct printbuf *err)
+{
+ struct bch_sb_field_downgrade *e = field_to_type(f, downgrade);
+
+ for_each_downgrade_entry(e, i) {
+ if (BCH_VERSION_MAJOR(le16_to_cpu(i->version)) !=
+ BCH_VERSION_MAJOR(le16_to_cpu(sb->version))) {
+ prt_printf(err, "downgrade entry with mismatched major version (%u != %u)",
+ BCH_VERSION_MAJOR(le16_to_cpu(i->version)),
+ BCH_VERSION_MAJOR(le16_to_cpu(sb->version)));
+ return -BCH_ERR_invalid_sb_downgrade;
+ }
+ }
+
+ return 0;
+}
+
+static void bch2_sb_downgrade_to_text(struct printbuf *out, struct bch_sb *sb,
+ struct bch_sb_field *f)
+{
+ struct bch_sb_field_downgrade *e = field_to_type(f, downgrade);
+
+ if (out->nr_tabstops <= 1)
+ printbuf_tabstop_push(out, 16);
+
+ for_each_downgrade_entry(e, i) {
+ prt_str(out, "version:");
+ prt_tab(out);
+ bch2_version_to_text(out, le16_to_cpu(i->version));
+ prt_newline(out);
+
+ prt_str(out, "recovery passes:");
+ prt_tab(out);
+ prt_bitflags(out, bch2_recovery_passes,
+ bch2_recovery_passes_from_stable(le64_to_cpu(i->recovery_passes[0])));
+ prt_newline(out);
+
+ prt_str(out, "errors:");
+ prt_tab(out);
+ bool first = true;
+ for (unsigned j = 0; j < le16_to_cpu(i->nr_errors); j++) {
+ if (!first)
+ prt_char(out, ',');
+ first = false;
+ unsigned e = le16_to_cpu(i->errors[j]);
+ prt_str(out, e < BCH_SB_ERR_MAX ? bch2_sb_error_strs[e] : "(unknown)");
+ }
+ prt_newline(out);
+ }
+}
+
+const struct bch_sb_field_ops bch_sb_field_ops_downgrade = {
+ .validate = bch2_sb_downgrade_validate,
+ .to_text = bch2_sb_downgrade_to_text,
+};
+
+int bch2_sb_downgrade_update(struct bch_fs *c)
+{
+ darray_char table = {};
+ int ret = 0;
+
+ for (const struct downgrade_entry *src = downgrade_table;
+ src < downgrade_table + ARRAY_SIZE(downgrade_table);
+ src++) {
+ if (BCH_VERSION_MAJOR(src->version) != BCH_VERSION_MAJOR(le16_to_cpu(c->disk_sb.sb->version)))
+ continue;
+
+ struct bch_sb_field_downgrade_entry *dst;
+ unsigned bytes = sizeof(*dst) + sizeof(dst->errors[0]) * src->nr_errors;
+
+ ret = darray_make_room(&table, bytes);
+ if (ret)
+ goto out;
+
+ dst = (void *) &darray_top(table);
+ dst->version = cpu_to_le16(src->version);
+ dst->recovery_passes[0] = cpu_to_le64(src->recovery_passes);
+ dst->recovery_passes[1] = 0;
+ dst->nr_errors = cpu_to_le16(src->nr_errors);
+ for (unsigned i = 0; i < src->nr_errors; i++)
+ dst->errors[i] = cpu_to_le16(src->errors[i]);
+
+ table.nr += bytes;
+ }
+
+ struct bch_sb_field_downgrade *d = bch2_sb_field_get(c->disk_sb.sb, downgrade);
+
+ unsigned sb_u64s = DIV_ROUND_UP(sizeof(*d) + table.nr, sizeof(u64));
+
+ if (d && le32_to_cpu(d->field.u64s) > sb_u64s)
+ goto out;
+
+ d = bch2_sb_field_resize(&c->disk_sb, downgrade, sb_u64s);
+ if (!d) {
+ ret = -BCH_ERR_ENOSPC_sb_downgrade;
+ goto out;
+ }
+
+ memcpy(d->entries, table.data, table.nr);
+ memset_u64s_tail(d->entries, 0, table.nr);
+out:
+ darray_exit(&table);
+ return ret;
+}
+
+void bch2_sb_set_downgrade(struct bch_fs *c, unsigned new_minor, unsigned old_minor)
+{
+ struct bch_sb_field_downgrade *d = bch2_sb_field_get(c->disk_sb.sb, downgrade);
+ if (!d)
+ return;
+
+ struct bch_sb_field_ext *ext = bch2_sb_field_get(c->disk_sb.sb, ext);
+
+ for_each_downgrade_entry(d, i) {
+ unsigned minor = BCH_VERSION_MINOR(le16_to_cpu(i->version));
+ if (new_minor < minor && minor <= old_minor) {
+ ext->recovery_passes_required[0] |= i->recovery_passes[0];
+ ext->recovery_passes_required[1] |= i->recovery_passes[1];
+
+ for (unsigned j = 0; j < le16_to_cpu(i->nr_errors); j++) {
+ unsigned e = le16_to_cpu(i->errors[j]);
+ if (e < BCH_SB_ERR_MAX)
+ __set_bit(e, c->sb.errors_silent);
+ if (e < sizeof(ext->errors_silent) * 8)
+ ext->errors_silent[e / 64] |= cpu_to_le64(BIT_ULL(e % 64));
+ }
+ }
+ }
+}