diff options
Diffstat (limited to 'fs/bcachefs/reflink.c')
-rw-r--r-- | fs/bcachefs/reflink.c | 304 |
1 files changed, 304 insertions, 0 deletions
diff --git a/fs/bcachefs/reflink.c b/fs/bcachefs/reflink.c new file mode 100644 index 000000000000..6d45ae24479d --- /dev/null +++ b/fs/bcachefs/reflink.c @@ -0,0 +1,304 @@ +// SPDX-License-Identifier: GPL-2.0 +#include "bcachefs.h" +#include "btree_update.h" +#include "extents.h" +#include "inode.h" +#include "io.h" +#include "reflink.h" + +#include <linux/sched/signal.h> + +/* reflink pointers */ + +const char *bch2_reflink_p_invalid(const struct bch_fs *c, struct bkey_s_c k) +{ + struct bkey_s_c_reflink_p p = bkey_s_c_to_reflink_p(k); + + if (bkey_val_bytes(p.k) != sizeof(*p.v)) + return "incorrect value size"; + + return NULL; +} + +void bch2_reflink_p_to_text(struct printbuf *out, struct bch_fs *c, + struct bkey_s_c k) +{ + struct bkey_s_c_reflink_p p = bkey_s_c_to_reflink_p(k); + + pr_buf(out, "idx %llu", le64_to_cpu(p.v->idx)); +} + +enum merge_result bch2_reflink_p_merge(struct bch_fs *c, + struct bkey_s _l, struct bkey_s _r) +{ + struct bkey_s_reflink_p l = bkey_s_to_reflink_p(_l); + struct bkey_s_reflink_p r = bkey_s_to_reflink_p(_r); + + if (le64_to_cpu(l.v->idx) + l.k->size != le64_to_cpu(r.v->idx)) + return BCH_MERGE_NOMERGE; + + if ((u64) l.k->size + r.k->size > KEY_SIZE_MAX) { + bch2_key_resize(l.k, KEY_SIZE_MAX); + __bch2_cut_front(l.k->p, _r); + return BCH_MERGE_PARTIAL; + } + + bch2_key_resize(l.k, l.k->size + r.k->size); + + return BCH_MERGE_MERGE; +} + +/* indirect extents */ + +const char *bch2_reflink_v_invalid(const struct bch_fs *c, struct bkey_s_c k) +{ + struct bkey_s_c_reflink_v r = bkey_s_c_to_reflink_v(k); + + if (bkey_val_bytes(r.k) < sizeof(*r.v)) + return "incorrect value size"; + + return bch2_bkey_ptrs_invalid(c, k); +} + +void bch2_reflink_v_to_text(struct printbuf *out, struct bch_fs *c, + struct bkey_s_c k) +{ + struct bkey_s_c_reflink_v r = bkey_s_c_to_reflink_v(k); + + pr_buf(out, "refcount: %llu ", le64_to_cpu(r.v->refcount)); + + bch2_bkey_ptrs_to_text(out, c, k); +} + +static int bch2_make_extent_indirect(struct btree_trans *trans, + struct btree_iter *extent_iter, + struct bkey_i_extent *e) +{ + struct bch_fs *c = trans->c; + struct btree_iter *reflink_iter; + struct bkey_s_c k; + struct bkey_i_reflink_v *r_v; + struct bkey_i_reflink_p *r_p; + int ret; + + for_each_btree_key(trans, reflink_iter, BTREE_ID_REFLINK, + POS(0, c->reflink_hint), + BTREE_ITER_INTENT|BTREE_ITER_SLOTS, k, ret) { + if (reflink_iter->pos.inode) { + bch2_btree_iter_set_pos(reflink_iter, POS_MIN); + continue; + } + + if (bkey_deleted(k.k) && e->k.size <= k.k->size) + break; + } + + if (ret) + goto err; + + /* rewind iter to start of hole, if necessary: */ + bch2_btree_iter_set_pos(reflink_iter, bkey_start_pos(k.k)); + + r_v = bch2_trans_kmalloc(trans, sizeof(*r_v) + bkey_val_bytes(&e->k)); + ret = PTR_ERR_OR_ZERO(r_v); + if (ret) + goto err; + + bkey_reflink_v_init(&r_v->k_i); + r_v->k.p = reflink_iter->pos; + bch2_key_resize(&r_v->k, e->k.size); + r_v->k.version = e->k.version; + + set_bkey_val_u64s(&r_v->k, bkey_val_u64s(&r_v->k) + + bkey_val_u64s(&e->k)); + r_v->v.refcount = 0; + memcpy(r_v->v.start, e->v.start, bkey_val_bytes(&e->k)); + + bch2_trans_update(trans, reflink_iter, &r_v->k_i); + + r_p = bch2_trans_kmalloc(trans, sizeof(*r_p)); + if (IS_ERR(r_p)) + return PTR_ERR(r_p); + + e->k.type = KEY_TYPE_reflink_p; + r_p = bkey_i_to_reflink_p(&e->k_i); + set_bkey_val_bytes(&r_p->k, sizeof(r_p->v)); + r_p->v.idx = cpu_to_le64(bkey_start_offset(&r_v->k)); + + bch2_trans_update(trans, extent_iter, &r_p->k_i); +err: + if (!IS_ERR(reflink_iter)) { + c->reflink_hint = reflink_iter->pos.offset; + bch2_trans_iter_put(trans, reflink_iter); + } + + return ret; +} + +static struct bkey_s_c get_next_src(struct btree_iter *iter, struct bpos end) +{ + struct bkey_s_c k = bch2_btree_iter_peek(iter); + int ret; + + for_each_btree_key_continue(iter, 0, k, ret) { + if (bkey_cmp(iter->pos, end) >= 0) + return bkey_s_c_null; + + if (k.k->type == KEY_TYPE_extent || + k.k->type == KEY_TYPE_reflink_p) + break; + } + + return k; +} + +s64 bch2_remap_range(struct bch_fs *c, + struct bpos dst_start, struct bpos src_start, + u64 remap_sectors, u64 *journal_seq, + u64 new_i_size, s64 *i_sectors_delta) +{ + struct btree_trans trans; + struct btree_iter *dst_iter, *src_iter; + struct bkey_s_c src_k; + BKEY_PADDED(k) new_dst, new_src; + struct bpos dst_end = dst_start, src_end = src_start; + struct bpos dst_want, src_want; + u64 src_done, dst_done; + int ret = 0, ret2 = 0; + + if (!percpu_ref_tryget(&c->writes)) + return -EROFS; + + if (!(c->sb.features & (1ULL << BCH_FEATURE_REFLINK))) { + mutex_lock(&c->sb_lock); + if (!(c->sb.features & (1ULL << BCH_FEATURE_REFLINK))) { + c->disk_sb.sb->features[0] |= + cpu_to_le64(1ULL << BCH_FEATURE_REFLINK); + + bch2_write_super(c); + } + mutex_unlock(&c->sb_lock); + } + + dst_end.offset += remap_sectors; + src_end.offset += remap_sectors; + + bch2_trans_init(&trans, c, BTREE_ITER_MAX, 4096); + + src_iter = bch2_trans_get_iter(&trans, BTREE_ID_EXTENTS, src_start, + BTREE_ITER_INTENT); + dst_iter = bch2_trans_get_iter(&trans, BTREE_ID_EXTENTS, dst_start, + BTREE_ITER_INTENT); + + while (1) { + bch2_trans_begin_updates(&trans); + trans.mem_top = 0; + + if (fatal_signal_pending(current)) { + ret = -EINTR; + goto err; + } + + src_k = get_next_src(src_iter, src_end); + ret = bkey_err(src_k); + if (ret) + goto btree_err; + + src_done = bpos_min(src_iter->pos, src_end).offset - + src_start.offset; + dst_want = POS(dst_start.inode, dst_start.offset + src_done); + + if (bkey_cmp(dst_iter->pos, dst_want) < 0) { + ret = bch2_fpunch_at(&trans, dst_iter, dst_want, + journal_seq, i_sectors_delta); + if (ret) + goto btree_err; + continue; + } + + BUG_ON(bkey_cmp(dst_iter->pos, dst_want)); + + if (!bkey_cmp(dst_iter->pos, dst_end)) + break; + + if (src_k.k->type == KEY_TYPE_extent) { + bkey_reassemble(&new_src.k, src_k); + src_k = bkey_i_to_s_c(&new_src.k); + + bch2_cut_front(src_iter->pos, &new_src.k); + bch2_cut_back(src_end, &new_src.k.k); + + ret = bch2_make_extent_indirect(&trans, src_iter, + bkey_i_to_extent(&new_src.k)); + if (ret) + goto btree_err; + + BUG_ON(src_k.k->type != KEY_TYPE_reflink_p); + } + + if (src_k.k->type == KEY_TYPE_reflink_p) { + struct bkey_s_c_reflink_p src_p = + bkey_s_c_to_reflink_p(src_k); + struct bkey_i_reflink_p *dst_p = + bkey_reflink_p_init(&new_dst.k); + + u64 offset = le64_to_cpu(src_p.v->idx) + + (src_iter->pos.offset - + bkey_start_offset(src_k.k)); + + dst_p->v.idx = cpu_to_le64(offset); + } else { + BUG(); + } + + new_dst.k.k.p = dst_iter->pos; + bch2_key_resize(&new_dst.k.k, + min(src_k.k->p.offset - src_iter->pos.offset, + dst_end.offset - dst_iter->pos.offset)); + + ret = bch2_extent_update(&trans, dst_iter, &new_dst.k, + NULL, journal_seq, + new_i_size, i_sectors_delta); + if (ret) + goto btree_err; + + dst_done = dst_iter->pos.offset - dst_start.offset; + src_want = POS(src_start.inode, src_start.offset + dst_done); + bch2_btree_iter_set_pos(src_iter, src_want); +btree_err: + if (ret == -EINTR) + ret = 0; + if (ret) + goto err; + } + + BUG_ON(bkey_cmp(dst_iter->pos, dst_end)); +err: + BUG_ON(bkey_cmp(dst_iter->pos, dst_end) > 0); + + dst_done = dst_iter->pos.offset - dst_start.offset; + new_i_size = min(dst_iter->pos.offset << 9, new_i_size); + + bch2_trans_begin(&trans); + + do { + struct bch_inode_unpacked inode_u; + struct btree_iter *inode_iter; + + inode_iter = bch2_inode_peek(&trans, &inode_u, + dst_start.inode, BTREE_ITER_INTENT); + ret2 = PTR_ERR_OR_ZERO(inode_iter); + + if (!ret2 && + inode_u.bi_size < new_i_size) + ret2 = bch2_inode_write(&trans, inode_iter, &inode_u) ?: + bch2_trans_commit(&trans, NULL, journal_seq, + BTREE_INSERT_ATOMIC); + } while (ret2 == -EINTR); + + ret = bch2_trans_exit(&trans) ?: ret; + + percpu_ref_put(&c->writes); + + return dst_done ?: ret ?: ret2; +} |