Adding upstream version 6.7.7.upstream/6.7.7

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 791 insertions, 0 deletions

diff --git a/fs/bcachefs/fs-io-pagecache.c b/fs/bcachefs/fs-io-pagecache.c
new file mode 100644
index 0000000000..ff664fd0d8
--- /dev/null
+++ b/fs/bcachefs/fs-io-pagecache.c
@@ -0,0 +1,791 @@
+// 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 <linux/pagevec.h>
+#include <linux/writeback.h>
+
+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)
+{
+	struct btree_trans *trans;
+	struct btree_iter iter;
+	struct bkey_s_c k;
+	struct bch_folio *s;
+	u64 offset = folio_sector(fs[0]);
+	unsigned folio_idx;
+	u32 snapshot;
+	bool need_set = false;
+	int ret;
+
+	for (folio_idx = 0; folio_idx < nr_folios; folio_idx++) {
+		s = bch2_folio_create(fs[folio_idx], GFP_KERNEL);
+		if (!s)
+			return -ENOMEM;
+
+		need_set |= !s->uptodate;
+	}
+
+	if (!need_set)
+		return 0;
+
+	folio_idx = 0;
+	trans = bch2_trans_get(c);
+retry:
+	bch2_trans_begin(trans);
+
+	ret = bch2_subvolume_get_snapshot(trans, inum.subvol, &snapshot);
+	if (ret)
+		goto err;
+
+	for_each_btree_key_norestart(trans, iter, BTREE_ID_extents,
+			   SPOS(inum.inum, offset, snapshot),
+			   BTREE_ITER_SLOTS, k, ret) {
+		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;
+	}
+
+	offset = iter.pos.offset;
+	bch2_trans_iter_exit(trans, &iter);
+err:
+	if (bch2_err_matches(ret, BCH_ERR_transaction_restart))
+		goto retry;
+	bch2_trans_put(trans);
+
+	return ret;
+}
+
+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();
+	}
+}
+
+void bch2_mark_pagecache_reserved(struct bch_inode_info *inode,
+				  u64 start, u64 end)
+{
+	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;
+	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++) {
+					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);
+}
+
+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);
+}
+
+int bch2_folio_reservation_get(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_create(folio, 0);
+	unsigned i, disk_sectors = 0, quota_sectors = 0;
+	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, &res->disk, disk_sectors, 0);
+		if (unlikely(ret))
+			return ret;
+	}
+
+	if (quota_sectors) {
+		ret = bch2_quota_reservation_add(c, inode, &res->quota,
+						 quota_sectors, true);
+		if (unlikely(ret)) {
+			struct disk_reservation tmp = {
+				.sectors = disk_sectors
+			};
+
+			bch2_disk_reservation_put(c, &tmp);
+			res->disk.sectors -= disk_sectors;
+			return ret;
+		}
+	}
+
+	return 0;
+}
+
+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 */