// SPDX-License-Identifier: GPL-2.0
/*
* io_misc.c - fallocate, fpunch, truncate:
*/
#include "bcachefs.h"
#include "alloc_foreground.h"
#include "bkey_buf.h"
#include "btree_update.h"
#include "buckets.h"
#include "clock.h"
#include "error.h"
#include "extents.h"
#include "extent_update.h"
#include "inode.h"
#include "io_misc.h"
#include "io_write.h"
#include "subvolume.h"
/* Overwrites whatever was present with zeroes: */
int bch2_extent_fallocate(struct btree_trans *trans,
subvol_inum inum,
struct btree_iter *iter,
unsigned sectors,
struct bch_io_opts opts,
s64 *i_sectors_delta,
struct write_point_specifier write_point)
{
struct bch_fs *c = trans->c;
struct disk_reservation disk_res = { 0 };
struct closure cl;
struct open_buckets open_buckets = { 0 };
struct bkey_s_c k;
struct bkey_buf old, new;
unsigned sectors_allocated = 0;
bool have_reservation = false;
bool unwritten = opts.nocow &&
c->sb.version >= bcachefs_metadata_version_unwritten_extents;
int ret;
bch2_bkey_buf_init(&old);
bch2_bkey_buf_init(&new);
closure_init_stack(&cl);
k = bch2_btree_iter_peek_slot(iter);
ret = bkey_err(k);
if (ret)
return ret;
sectors = min_t(u64, sectors, k.k->p.offset - iter->pos.offset);
if (!have_reservation) {
unsigned new_replicas =
max(0, (int) opts.data_replicas -
(int) bch2_bkey_nr_ptrs_fully_allocated(k));
/*
* Get a disk reservation before (in the nocow case) calling
* into the allocator:
*/
ret = bch2_disk_reservation_get(c, &disk_res, sectors, new_replicas, 0);
if (unlikely(ret))
goto err;
bch2_bkey_buf_reassemble(&old, c, k);
}
if (have_reservation) {
if (!bch2_extents_match(k, bkey_i_to_s_c(old.k)))
goto err;
bch2_key_resize(&new.k->k, sectors);
} else if (!unwritten) {
struct bkey_i_reservation *reservation;
bch2_bkey_buf_realloc(&new, c, sizeof(*reservation) / sizeof(u64));
reservation = bkey_reservation_init(new.k);
reservation->k.p = iter->pos;
bch2_key_resize(&reservation->k, sectors);
reservation->v.nr_replicas = opts.data_replicas;
} else {
struct bkey_i_extent *e;
struct bch_devs_list devs_have;
struct write_point *wp;
struct bch_extent_ptr *ptr;
devs_have.nr = 0;
bch2_bkey_buf_realloc(&new, c, BKEY_EXTENT_U64s_MAX);
e = bkey_extent_init(new.k);
e->k.p = iter->pos;
ret = bch2_alloc_sectors_start_trans(trans,
opts.foreground_target,
false,
write_point,
&devs_have,
opts.data_replicas,
opts.data_replicas,
BCH_WATERMARK_normal, 0, &cl, &wp);
if (bch2_err_matches(ret, BCH_ERR_operation_blocked))
ret = -BCH_ERR_transaction_restart_nested;
if (ret)
goto err;
sectors = min(sectors, wp->sectors_free);
sectors_allocated = sectors;
bch2_key_resize(&e->k, sectors);
bch2_open_bucket_get(c, wp, &open_buckets);
bch2_alloc_sectors_append_ptrs(c, wp, &e->k_i, sectors, false);
bch2_alloc_sectors_done(c, wp);
extent_for_each_ptr(extent_i_to_s(e), ptr)
ptr->unwritten = true;
}
have_reservation = true;
ret = bch2_extent_update(trans, inum, iter, new.k, &disk_res,
0, i_sectors_delta, true);
err:
if (!ret && sectors_allocated)
bch2_increment_clock(c, sectors_allocated, WRITE);
bch2_open_buckets_put(c, &open_buckets);
bch2_disk_reservation_put(c, &disk_res);
bch2_bkey_buf_exit(&new, c);
bch2_bkey_buf_exit(&old, c);
if (closure_nr_remaining(&cl) != 1) {
bch2_trans_unlock(trans);
closure_sync(&cl);
}
return ret;
}
/*
* Returns -BCH_ERR_transacton_restart if we had to drop locks:
*/
int bch2_fpunch_at(struct btree_trans *trans, struct btree_iter *iter,
subvol_inum inum, u64 end,
s64 *i_sectors_delta)
{
struct bch_fs *c = trans->c;
unsigned max_sectors = KEY_SIZE_MAX & (~0 << c->block_bits);
struct bpos end_pos = POS(inum.inum, end);
struct bkey_s_c k;
int ret = 0, ret2 = 0;
u32 snapshot;
while (!ret ||
bch2_err_matches(ret, BCH_ERR_transaction_restart)) {
struct disk_reservation disk_res =
bch2_disk_reservation_init(c, 0);
struct bkey_i delete;
if (ret)
ret2 = ret;
bch2_trans_begin(trans);
ret = bch2_subvolume_get_snapshot(trans, inum.subvol, &snapshot);
if (ret)
continue;
bch2_btree_iter_set_snapshot(iter, snapshot);
/*
* peek_upto() doesn't have ideal semantics for extents:
*/
k = bch2_btree_iter_peek_upto(iter, end_pos);
if (!k.k)
break;
ret = bkey_err(k);
if (ret)
continue;
bkey_init(&delete.k);
delete.k.p = iter->pos;
/* create the biggest key we can */
bch2_key_resize(&delete.k, max_sectors);
bch2_cut_back(end_pos, &delete);
ret = bch2_extent_update(trans, inum, iter, &delete,
&disk_res, 0, i_sectors_delta, false);
bch2_disk_reservation_put(c, &disk_res);
}
return ret ?: ret2;
}
int bch2_fpunch(struct bch_fs *c, subvol_inum inum, u64 start, u64 end,
s64 *i_sectors_delta)
{
struct btree_trans trans;
struct btree_iter iter;
int ret;
bch2_trans_init(&trans, c, BTREE_ITER_MAX, 1024);
bch2_trans_iter_init(&trans, &iter, BTREE_ID_extents,
POS(inum.inum, start),
BTREE_ITER_INTENT);
ret = bch2_fpunch_at(&trans, &iter, inum, end, i_sectors_delta);
bch2_trans_iter_exit(&trans, &iter);
bch2_trans_exit(&trans);
if (bch2_err_matches(ret, BCH_ERR_transaction_restart))
ret = 0;
return ret;
}
static int truncate_set_isize(struct btree_trans *trans,
subvol_inum inum,
u64 new_i_size)
{
struct btree_iter iter = { NULL };
struct bch_inode_unpacked inode_u;
int ret;
ret = bch2_inode_peek(trans, &iter, &inode_u, inum, BTREE_ITER_INTENT) ?:
(inode_u.bi_size = new_i_size, 0) ?:
bch2_inode_write(trans, &iter, &inode_u);
bch2_trans_iter_exit(trans, &iter);
return ret;
}
int bch2_truncate(struct bch_fs *c, subvol_inum inum, u64 new_i_size, u64 *i_sectors_delta)
{
struct btree_trans trans;
struct btree_iter fpunch_iter;
int ret;
bch2_trans_init(&trans, c, BTREE_ITER_MAX, 1024);
bch2_trans_iter_init(&trans, &fpunch_iter, BTREE_ID_extents,
POS(inum.inum, round_up(new_i_size, block_bytes(c)) >> 9),
BTREE_ITER_INTENT);
ret = commit_do(&trans, NULL, NULL, BTREE_INSERT_NOFAIL,
truncate_set_isize(&trans, inum, new_i_size));
if (ret)
goto err;
ret = bch2_fpunch_at(&trans, &fpunch_iter, inum, U64_MAX, i_sectors_delta);
if (bch2_err_matches(ret, BCH_ERR_transaction_restart))
ret = 0;
if (ret)
goto err;
err:
bch2_trans_iter_exit(&trans, &fpunch_iter);
bch2_trans_exit(&trans);
bch2_fs_fatal_err_on(ret, c, "%s: error truncating %u:%llu: %s",
__func__, inum.subvol, inum.inum, bch2_err_str(ret));
return ret;
}
static int adjust_i_size(struct btree_trans *trans, subvol_inum inum, u64 offset, s64 len)
{
struct btree_iter iter;
struct bch_inode_unpacked inode_u;
int ret;
offset <<= 9;
len <<= 9;
ret = bch2_inode_peek(trans, &iter, &inode_u, inum, BTREE_ITER_INTENT);
if (ret)
return ret;
if (len > 0) {
if (MAX_LFS_FILESIZE - inode_u.bi_size < len) {
ret = -EFBIG;
goto err;
}
if (offset >= inode_u.bi_size) {
ret = -EINVAL;
goto err;
}
}
inode_u.bi_size += len;
inode_u.bi_mtime = inode_u.bi_ctime = bch2_current_time(trans->c);
ret = bch2_inode_write(trans, &iter, &inode_u);
err:
bch2_trans_iter_exit(trans, &iter);
return ret;
}
int bch2_fcollapse_finsert(struct bch_fs *c, subvol_inum inum,
u64 offset, u64 len, bool insert,
s64 *i_sectors_delta)
{
struct bkey_buf copy;
struct btree_trans trans;
struct btree_iter src = { NULL }, dst = { NULL }, del = { NULL };
s64 shift = insert ? len : -len;
int ret = 0;
bch2_bkey_buf_init(©);
bch2_trans_init(&trans, c, 0, 1024);
bch2_trans_iter_init(&trans, &src, BTREE_ID_extents,
POS(inum.inum, U64_MAX),
BTREE_ITER_INTENT);
bch2_trans_copy_iter(&dst, &src);
bch2_trans_copy_iter(&del, &src);
if (insert) {
ret = commit_do(&trans, NULL, NULL, BTREE_INSERT_NOFAIL,
adjust_i_size(&trans, inum, offset, len));
if (ret)
goto err;
} else {
bch2_btree_iter_set_pos(&src, POS(inum.inum, offset));
ret = bch2_fpunch_at(&trans, &src, inum, offset + len, i_sectors_delta);
if (ret && !bch2_err_matches(ret, BCH_ERR_transaction_restart))
goto err;
bch2_btree_iter_set_pos(&src, POS(inum.inum, offset + len));
}
while (ret == 0 || bch2_err_matches(ret, BCH_ERR_transaction_restart)) {
struct disk_reservation disk_res =
bch2_disk_reservation_init(c, 0);
struct bkey_i delete;
struct bkey_s_c k;
struct bpos next_pos;
struct bpos move_pos = POS(inum.inum, offset);
struct bpos atomic_end;
unsigned trigger_flags = 0;
u32 snapshot;
bch2_trans_begin(&trans);
ret = bch2_subvolume_get_snapshot(&trans, inum.subvol, &snapshot);
if (ret)
continue;
bch2_btree_iter_set_snapshot(&src, snapshot);
bch2_btree_iter_set_snapshot(&dst, snapshot);
bch2_btree_iter_set_snapshot(&del, snapshot);
bch2_trans_begin(&trans);
k = insert
? bch2_btree_iter_peek_prev(&src)
: bch2_btree_iter_peek_upto(&src, POS(inum.inum, U64_MAX));
if ((ret = bkey_err(k)))
continue;
if (!k.k || k.k->p.inode != inum.inum)
break;
if (insert &&
bkey_le(k.k->p, POS(inum.inum, offset)))
break;
reassemble:
bch2_bkey_buf_reassemble(©, c, k);
if (insert &&
bkey_lt(bkey_start_pos(k.k), move_pos))
bch2_cut_front(move_pos, copy.k);
copy.k->k.p.offset += shift;
bch2_btree_iter_set_pos(&dst, bkey_start_pos(©.k->k));
ret = bch2_extent_atomic_end(&trans, &dst, copy.k, &atomic_end);
if (ret)
continue;
if (!bkey_eq(atomic_end, copy.k->k.p)) {
if (insert) {
move_pos = atomic_end;
move_pos.offset -= shift;
goto reassemble;
} else {
bch2_cut_back(atomic_end, copy.k);
}
}
bkey_init(&delete.k);
delete.k.p = copy.k->k.p;
delete.k.size = copy.k->k.size;
delete.k.p.offset -= shift;
bch2_btree_iter_set_pos(&del, bkey_start_pos(&delete.k));
next_pos = insert ? bkey_start_pos(&delete.k) : delete.k.p;
if (copy.k->k.size != k.k->size) {
/* We might end up splitting compressed extents: */
unsigned nr_ptrs =
bch2_bkey_nr_ptrs_allocated(bkey_i_to_s_c(copy.k));
ret = bch2_disk_reservation_get(c, &disk_res,
copy.k->k.size, nr_ptrs,
BCH_DISK_RESERVATION_NOFAIL);
BUG_ON(ret);
}
ret = bch2_btree_iter_traverse(&del) ?:
bch2_trans_update(&trans, &del, &delete, trigger_flags) ?:
bch2_trans_update(&trans, &dst, copy.k, trigger_flags) ?:
bch2_trans_commit(&trans, &disk_res, NULL,
BTREE_INSERT_NOFAIL);
bch2_disk_reservation_put(c, &disk_res);
if (!ret)
bch2_btree_iter_set_pos(&src, next_pos);
}
if (ret && !bch2_err_matches(ret, BCH_ERR_transaction_restart))
goto err;
if (!insert) {
ret = commit_do(&trans, NULL, NULL, BTREE_INSERT_NOFAIL,
adjust_i_size(&trans, inum, offset, -len));
} else {
/* We need an inode update to update bi_journal_seq for fsync: */
ret = commit_do(&trans, NULL, NULL, BTREE_INSERT_NOFAIL,
adjust_i_size(&trans, inum, 0, 0));
}
err:
bch2_trans_iter_exit(&trans, &del);
bch2_trans_iter_exit(&trans, &dst);
bch2_trans_iter_exit(&trans, &src);
bch2_trans_exit(&trans);
bch2_bkey_buf_exit(©, c);
return ret;
}