// SPDX-License-Identifier: GPL-2.0 #ifndef NO_BCACHEFS_FS #include "bcachefs.h" #include "btree_iter.h" #include "extents.h" #include "fs-io.h" #include "fs-io-pagecache.h" #include "subvolume.h" #include #include int bch2_filemap_get_contig_folios_d(struct address_space *mapping, loff_t start, u64 end, fgf_t fgp_flags, gfp_t gfp, folios *fs) { struct folio *f; u64 pos = start; int ret = 0; while (pos < end) { if ((u64) pos >= (u64) start + (1ULL << 20)) fgp_flags &= ~FGP_CREAT; ret = darray_make_room_gfp(fs, 1, gfp & GFP_KERNEL); if (ret) break; f = __filemap_get_folio(mapping, pos >> PAGE_SHIFT, fgp_flags, gfp); if (IS_ERR_OR_NULL(f)) break; BUG_ON(fs->nr && folio_pos(f) != pos); pos = folio_end_pos(f); darray_push(fs, f); } if (!fs->nr && !ret && (fgp_flags & FGP_CREAT)) ret = -ENOMEM; return fs->nr ? 0 : ret; } /* pagecache_block must be held */ int bch2_write_invalidate_inode_pages_range(struct address_space *mapping, loff_t start, loff_t end) { int ret; /* * XXX: the way this is currently implemented, we can spin if a process * is continually redirtying a specific page */ do { if (!mapping->nrpages) return 0; ret = filemap_write_and_wait_range(mapping, start, end); if (ret) break; if (!mapping->nrpages) return 0; ret = invalidate_inode_pages2_range(mapping, start >> PAGE_SHIFT, end >> PAGE_SHIFT); } while (ret == -EBUSY); return ret; } #if 0 /* Useful for debug tracing: */ static const char * const bch2_folio_sector_states[] = { #define x(n) #n, BCH_FOLIO_SECTOR_STATE() #undef x NULL }; #endif static inline enum bch_folio_sector_state folio_sector_dirty(enum bch_folio_sector_state state) { switch (state) { case SECTOR_unallocated: return SECTOR_dirty; case SECTOR_reserved: return SECTOR_dirty_reserved; default: return state; } } static inline enum bch_folio_sector_state folio_sector_undirty(enum bch_folio_sector_state state) { switch (state) { case SECTOR_dirty: return SECTOR_unallocated; case SECTOR_dirty_reserved: return SECTOR_reserved; default: return state; } } static inline enum bch_folio_sector_state folio_sector_reserve(enum bch_folio_sector_state state) { switch (state) { case SECTOR_unallocated: return SECTOR_reserved; case SECTOR_dirty: return SECTOR_dirty_reserved; default: return state; } } /* for newly allocated folios: */ struct bch_folio *__bch2_folio_create(struct folio *folio, gfp_t gfp) { struct bch_folio *s; s = kzalloc(sizeof(*s) + sizeof(struct bch_folio_sector) * folio_sectors(folio), gfp); if (!s) return NULL; spin_lock_init(&s->lock); folio_attach_private(folio, s); return s; } struct bch_folio *bch2_folio_create(struct folio *folio, gfp_t gfp) { return bch2_folio(folio) ?: __bch2_folio_create(folio, gfp); } static unsigned bkey_to_sector_state(struct bkey_s_c k) { if (bkey_extent_is_reservation(k)) return SECTOR_reserved; if (bkey_extent_is_allocation(k.k)) return SECTOR_allocated; return SECTOR_unallocated; } static void __bch2_folio_set(struct folio *folio, unsigned pg_offset, unsigned pg_len, unsigned nr_ptrs, unsigned state) { struct bch_folio *s = bch2_folio(folio); unsigned i, sectors = folio_sectors(folio); BUG_ON(pg_offset >= sectors); BUG_ON(pg_offset + pg_len > sectors); spin_lock(&s->lock); for (i = pg_offset; i < pg_offset + pg_len; i++) { s->s[i].nr_replicas = nr_ptrs; bch2_folio_sector_set(folio, s, i, state); } if (i == sectors) s->uptodate = true; spin_unlock(&s->lock); } /* * Initialize bch_folio state (allocated/unallocated, nr_replicas) from the * extents btree: */ int bch2_folio_set(struct bch_fs *c, subvol_inum inum, struct folio **fs, unsigned nr_folios) { u64 offset = folio_sector(fs[0]); bool need_set = false; for (unsigned folio_idx = 0; folio_idx < nr_folios; folio_idx++) { struct bch_folio *s = bch2_folio_create(fs[folio_idx], GFP_KERNEL); if (!s) return -ENOMEM; need_set |= !s->uptodate; } if (!need_set) return 0; unsigned folio_idx = 0; return bch2_trans_run(c, for_each_btree_key_in_subvolume_upto(trans, iter, BTREE_ID_extents, POS(inum.inum, offset), POS(inum.inum, U64_MAX), inum.subvol, BTREE_ITER_slots, k, ({ unsigned nr_ptrs = bch2_bkey_nr_ptrs_fully_allocated(k); unsigned state = bkey_to_sector_state(k); while (folio_idx < nr_folios) { struct folio *folio = fs[folio_idx]; u64 folio_start = folio_sector(folio); u64 folio_end = folio_end_sector(folio); unsigned folio_offset = max(bkey_start_offset(k.k), folio_start) - folio_start; unsigned folio_len = min(k.k->p.offset, folio_end) - folio_offset - folio_start; BUG_ON(k.k->p.offset < folio_start); BUG_ON(bkey_start_offset(k.k) > folio_end); if (!bch2_folio(folio)->uptodate) __bch2_folio_set(folio, folio_offset, folio_len, nr_ptrs, state); if (k.k->p.offset < folio_end) break; folio_idx++; } if (folio_idx == nr_folios) break; 0; }))); } void bch2_bio_page_state_set(struct bio *bio, struct bkey_s_c k) { struct bvec_iter iter; struct folio_vec fv; unsigned nr_ptrs = k.k->type == KEY_TYPE_reflink_v ? 0 : bch2_bkey_nr_ptrs_fully_allocated(k); unsigned state = bkey_to_sector_state(k); bio_for_each_folio(fv, bio, iter) __bch2_folio_set(fv.fv_folio, fv.fv_offset >> 9, fv.fv_len >> 9, nr_ptrs, state); } void bch2_mark_pagecache_unallocated(struct bch_inode_info *inode, u64 start, u64 end) { pgoff_t index = start >> PAGE_SECTORS_SHIFT; pgoff_t end_index = (end - 1) >> PAGE_SECTORS_SHIFT; struct folio_batch fbatch; unsigned i, j; if (end <= start) return; folio_batch_init(&fbatch); while (filemap_get_folios(inode->v.i_mapping, &index, end_index, &fbatch)) { for (i = 0; i < folio_batch_count(&fbatch); i++) { struct folio *folio = fbatch.folios[i]; u64 folio_start = folio_sector(folio); u64 folio_end = folio_end_sector(folio); unsigned folio_offset = max(start, folio_start) - folio_start; unsigned folio_len = min(end, folio_end) - folio_offset - folio_start; struct bch_folio *s; BUG_ON(end <= folio_start); folio_lock(folio); s = bch2_folio(folio); if (s) { spin_lock(&s->lock); for (j = folio_offset; j < folio_offset + folio_len; j++) s->s[j].nr_replicas = 0; spin_unlock(&s->lock); } folio_unlock(folio); } folio_batch_release(&fbatch); cond_resched(); } } int bch2_mark_pagecache_reserved(struct bch_inode_info *inode, u64 *start, u64 end, bool nonblocking) { struct bch_fs *c = inode->v.i_sb->s_fs_info; pgoff_t index = *start >> PAGE_SECTORS_SHIFT; pgoff_t end_index = (end - 1) >> PAGE_SECTORS_SHIFT; struct folio_batch fbatch; s64 i_sectors_delta = 0; int ret = 0; if (end <= *start) return 0; folio_batch_init(&fbatch); while (filemap_get_folios(inode->v.i_mapping, &index, end_index, &fbatch)) { for (unsigned i = 0; i < folio_batch_count(&fbatch); i++) { struct folio *folio = fbatch.folios[i]; if (!nonblocking) folio_lock(folio); else if (!folio_trylock(folio)) { folio_batch_release(&fbatch); ret = -EAGAIN; break; } u64 folio_start = folio_sector(folio); u64 folio_end = folio_end_sector(folio); BUG_ON(end <= folio_start); *start = min(end, folio_end); struct bch_folio *s = bch2_folio(folio); if (s) { unsigned folio_offset = max(*start, folio_start) - folio_start; unsigned folio_len = min(end, folio_end) - folio_offset - folio_start; spin_lock(&s->lock); for (unsigned j = folio_offset; j < folio_offset + folio_len; j++) { i_sectors_delta -= s->s[j].state == SECTOR_dirty; bch2_folio_sector_set(folio, s, j, folio_sector_reserve(s->s[j].state)); } spin_unlock(&s->lock); } folio_unlock(folio); } folio_batch_release(&fbatch); cond_resched(); } bch2_i_sectors_acct(c, inode, NULL, i_sectors_delta); return ret; } static inline unsigned sectors_to_reserve(struct bch_folio_sector *s, unsigned nr_replicas) { return max(0, (int) nr_replicas - s->nr_replicas - s->replicas_reserved); } int bch2_get_folio_disk_reservation(struct bch_fs *c, struct bch_inode_info *inode, struct folio *folio, bool check_enospc) { struct bch_folio *s = bch2_folio_create(folio, 0); unsigned nr_replicas = inode_nr_replicas(c, inode); struct disk_reservation disk_res = { 0 }; unsigned i, sectors = folio_sectors(folio), disk_res_sectors = 0; int ret; if (!s) return -ENOMEM; for (i = 0; i < sectors; i++) disk_res_sectors += sectors_to_reserve(&s->s[i], nr_replicas); if (!disk_res_sectors) return 0; ret = bch2_disk_reservation_get(c, &disk_res, disk_res_sectors, 1, !check_enospc ? BCH_DISK_RESERVATION_NOFAIL : 0); if (unlikely(ret)) return ret; for (i = 0; i < sectors; i++) s->s[i].replicas_reserved += sectors_to_reserve(&s->s[i], nr_replicas); return 0; } void bch2_folio_reservation_put(struct bch_fs *c, struct bch_inode_info *inode, struct bch2_folio_reservation *res) { bch2_disk_reservation_put(c, &res->disk); bch2_quota_reservation_put(c, inode, &res->quota); } static int __bch2_folio_reservation_get(struct bch_fs *c, struct bch_inode_info *inode, struct folio *folio, struct bch2_folio_reservation *res, size_t offset, size_t len, bool partial) { struct bch_folio *s = bch2_folio_create(folio, 0); unsigned i, disk_sectors = 0, quota_sectors = 0; struct disk_reservation disk_res = {}; size_t reserved = len; int ret; if (!s) return -ENOMEM; BUG_ON(!s->uptodate); for (i = round_down(offset, block_bytes(c)) >> 9; i < round_up(offset + len, block_bytes(c)) >> 9; i++) { disk_sectors += sectors_to_reserve(&s->s[i], res->disk.nr_replicas); quota_sectors += s->s[i].state == SECTOR_unallocated; } if (disk_sectors) { ret = bch2_disk_reservation_add(c, &disk_res, disk_sectors, partial ? BCH_DISK_RESERVATION_PARTIAL : 0); if (unlikely(ret)) return ret; if (unlikely(disk_res.sectors != disk_sectors)) { disk_sectors = quota_sectors = 0; for (i = round_down(offset, block_bytes(c)) >> 9; i < round_up(offset + len, block_bytes(c)) >> 9; i++) { disk_sectors += sectors_to_reserve(&s->s[i], res->disk.nr_replicas); if (disk_sectors > disk_res.sectors) { /* * Make sure to get a reservation that's * aligned to the filesystem blocksize: */ unsigned reserved_offset = round_down(i << 9, block_bytes(c)); reserved = clamp(reserved_offset, offset, offset + len) - offset; if (!reserved) { bch2_disk_reservation_put(c, &disk_res); return -BCH_ERR_ENOSPC_disk_reservation; } break; } quota_sectors += s->s[i].state == SECTOR_unallocated; } } } if (quota_sectors) { ret = bch2_quota_reservation_add(c, inode, &res->quota, quota_sectors, true); if (unlikely(ret)) { bch2_disk_reservation_put(c, &disk_res); return ret; } } res->disk.sectors += disk_res.sectors; return partial ? reserved : 0; } int bch2_folio_reservation_get(struct bch_fs *c, struct bch_inode_info *inode, struct folio *folio, struct bch2_folio_reservation *res, size_t offset, size_t len) { return __bch2_folio_reservation_get(c, inode, folio, res, offset, len, false); } ssize_t bch2_folio_reservation_get_partial(struct bch_fs *c, struct bch_inode_info *inode, struct folio *folio, struct bch2_folio_reservation *res, size_t offset, size_t len) { return __bch2_folio_reservation_get(c, inode, folio, res, offset, len, true); } static void bch2_clear_folio_bits(struct folio *folio) { struct bch_inode_info *inode = to_bch_ei(folio->mapping->host); struct bch_fs *c = inode->v.i_sb->s_fs_info; struct bch_folio *s = bch2_folio(folio); struct disk_reservation disk_res = { 0 }; int i, sectors = folio_sectors(folio), dirty_sectors = 0; if (!s) return; EBUG_ON(!folio_test_locked(folio)); EBUG_ON(folio_test_writeback(folio)); for (i = 0; i < sectors; i++) { disk_res.sectors += s->s[i].replicas_reserved; s->s[i].replicas_reserved = 0; dirty_sectors -= s->s[i].state == SECTOR_dirty; bch2_folio_sector_set(folio, s, i, folio_sector_undirty(s->s[i].state)); } bch2_disk_reservation_put(c, &disk_res); bch2_i_sectors_acct(c, inode, NULL, dirty_sectors); bch2_folio_release(folio); } void bch2_set_folio_dirty(struct bch_fs *c, struct bch_inode_info *inode, struct folio *folio, struct bch2_folio_reservation *res, unsigned offset, unsigned len) { struct bch_folio *s = bch2_folio(folio); unsigned i, dirty_sectors = 0; WARN_ON((u64) folio_pos(folio) + offset + len > round_up((u64) i_size_read(&inode->v), block_bytes(c))); BUG_ON(!s->uptodate); spin_lock(&s->lock); for (i = round_down(offset, block_bytes(c)) >> 9; i < round_up(offset + len, block_bytes(c)) >> 9; i++) { unsigned sectors = sectors_to_reserve(&s->s[i], res->disk.nr_replicas); /* * This can happen if we race with the error path in * bch2_writepage_io_done(): */ sectors = min_t(unsigned, sectors, res->disk.sectors); s->s[i].replicas_reserved += sectors; res->disk.sectors -= sectors; dirty_sectors += s->s[i].state == SECTOR_unallocated; bch2_folio_sector_set(folio, s, i, folio_sector_dirty(s->s[i].state)); } spin_unlock(&s->lock); bch2_i_sectors_acct(c, inode, &res->quota, dirty_sectors); if (!folio_test_dirty(folio)) filemap_dirty_folio(inode->v.i_mapping, folio); } vm_fault_t bch2_page_fault(struct vm_fault *vmf) { struct file *file = vmf->vma->vm_file; struct address_space *mapping = file->f_mapping; struct address_space *fdm = faults_disabled_mapping(); struct bch_inode_info *inode = file_bch_inode(file); vm_fault_t ret; if (fdm == mapping) return VM_FAULT_SIGBUS; /* Lock ordering: */ if (fdm > mapping) { struct bch_inode_info *fdm_host = to_bch_ei(fdm->host); if (bch2_pagecache_add_tryget(inode)) goto got_lock; bch2_pagecache_block_put(fdm_host); bch2_pagecache_add_get(inode); bch2_pagecache_add_put(inode); bch2_pagecache_block_get(fdm_host); /* Signal that lock has been dropped: */ set_fdm_dropped_locks(); return VM_FAULT_SIGBUS; } bch2_pagecache_add_get(inode); got_lock: ret = filemap_fault(vmf); bch2_pagecache_add_put(inode); return ret; } vm_fault_t bch2_page_mkwrite(struct vm_fault *vmf) { struct folio *folio = page_folio(vmf->page); struct file *file = vmf->vma->vm_file; struct bch_inode_info *inode = file_bch_inode(file); struct address_space *mapping = file->f_mapping; struct bch_fs *c = inode->v.i_sb->s_fs_info; struct bch2_folio_reservation res; unsigned len; loff_t isize; vm_fault_t ret; bch2_folio_reservation_init(c, inode, &res); sb_start_pagefault(inode->v.i_sb); file_update_time(file); /* * Not strictly necessary, but helps avoid dio writes livelocking in * bch2_write_invalidate_inode_pages_range() - can drop this if/when we get * a bch2_write_invalidate_inode_pages_range() that works without dropping * page lock before invalidating page */ bch2_pagecache_add_get(inode); folio_lock(folio); isize = i_size_read(&inode->v); if (folio->mapping != mapping || folio_pos(folio) >= isize) { folio_unlock(folio); ret = VM_FAULT_NOPAGE; goto out; } len = min_t(loff_t, folio_size(folio), isize - folio_pos(folio)); if (bch2_folio_set(c, inode_inum(inode), &folio, 1) ?: bch2_folio_reservation_get(c, inode, folio, &res, 0, len)) { folio_unlock(folio); ret = VM_FAULT_SIGBUS; goto out; } bch2_set_folio_dirty(c, inode, folio, &res, 0, len); bch2_folio_reservation_put(c, inode, &res); folio_wait_stable(folio); ret = VM_FAULT_LOCKED; out: bch2_pagecache_add_put(inode); sb_end_pagefault(inode->v.i_sb); return ret; } void bch2_invalidate_folio(struct folio *folio, size_t offset, size_t length) { if (offset || length < folio_size(folio)) return; bch2_clear_folio_bits(folio); } bool bch2_release_folio(struct folio *folio, gfp_t gfp_mask) { if (folio_test_dirty(folio) || folio_test_writeback(folio)) return false; bch2_clear_folio_bits(folio); return true; } /* fseek: */ static int folio_data_offset(struct folio *folio, loff_t pos, unsigned min_replicas) { struct bch_folio *s = bch2_folio(folio); unsigned i, sectors = folio_sectors(folio); if (s) for (i = folio_pos_to_s(folio, pos); i < sectors; i++) if (s->s[i].state >= SECTOR_dirty && s->s[i].nr_replicas + s->s[i].replicas_reserved >= min_replicas) return i << SECTOR_SHIFT; return -1; } loff_t bch2_seek_pagecache_data(struct inode *vinode, loff_t start_offset, loff_t end_offset, unsigned min_replicas, bool nonblock) { struct folio_batch fbatch; pgoff_t start_index = start_offset >> PAGE_SHIFT; pgoff_t end_index = end_offset >> PAGE_SHIFT; pgoff_t index = start_index; unsigned i; loff_t ret; int offset; folio_batch_init(&fbatch); while (filemap_get_folios(vinode->i_mapping, &index, end_index, &fbatch)) { for (i = 0; i < folio_batch_count(&fbatch); i++) { struct folio *folio = fbatch.folios[i]; if (!nonblock) { folio_lock(folio); } else if (!folio_trylock(folio)) { folio_batch_release(&fbatch); return -EAGAIN; } offset = folio_data_offset(folio, max(folio_pos(folio), start_offset), min_replicas); if (offset >= 0) { ret = clamp(folio_pos(folio) + offset, start_offset, end_offset); folio_unlock(folio); folio_batch_release(&fbatch); return ret; } folio_unlock(folio); } folio_batch_release(&fbatch); cond_resched(); } return end_offset; } /* * Search for a hole in a folio. * * The filemap layer returns -ENOENT if no folio exists, so reuse the same error * code to indicate a pagecache hole exists at the returned offset. Otherwise * return 0 if the folio is filled with data, or an error code. This function * can return -EAGAIN if nonblock is specified. */ static int folio_hole_offset(struct address_space *mapping, loff_t *offset, unsigned min_replicas, bool nonblock) { struct folio *folio; struct bch_folio *s; unsigned i, sectors; int ret = -ENOENT; folio = __filemap_get_folio(mapping, *offset >> PAGE_SHIFT, FGP_LOCK|(nonblock ? FGP_NOWAIT : 0), 0); if (IS_ERR(folio)) return PTR_ERR(folio); s = bch2_folio(folio); if (!s) goto unlock; sectors = folio_sectors(folio); for (i = folio_pos_to_s(folio, *offset); i < sectors; i++) if (s->s[i].state < SECTOR_dirty || s->s[i].nr_replicas + s->s[i].replicas_reserved < min_replicas) { *offset = max(*offset, folio_pos(folio) + (i << SECTOR_SHIFT)); goto unlock; } *offset = folio_end_pos(folio); ret = 0; unlock: folio_unlock(folio); folio_put(folio); return ret; } loff_t bch2_seek_pagecache_hole(struct inode *vinode, loff_t start_offset, loff_t end_offset, unsigned min_replicas, bool nonblock) { struct address_space *mapping = vinode->i_mapping; loff_t offset = start_offset; loff_t ret = 0; while (!ret && offset < end_offset) ret = folio_hole_offset(mapping, &offset, min_replicas, nonblock); if (ret && ret != -ENOENT) return ret; return min(offset, end_offset); } int bch2_clamp_data_hole(struct inode *inode, u64 *hole_start, u64 *hole_end, unsigned min_replicas, bool nonblock) { loff_t ret; ret = bch2_seek_pagecache_hole(inode, *hole_start << 9, *hole_end << 9, min_replicas, nonblock) >> 9; if (ret < 0) return ret; *hole_start = ret; if (*hole_start == *hole_end) return 0; ret = bch2_seek_pagecache_data(inode, *hole_start << 9, *hole_end << 9, min_replicas, nonblock) >> 9; if (ret < 0) return ret; *hole_end = ret; return 0; } #endif /* NO_BCACHEFS_FS */