diff options
Diffstat (limited to 'fs/bcachefs/sb-downgrade.c')
-rw-r--r-- | fs/bcachefs/sb-downgrade.c | 188 |
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)); + } + } + } +} |