bcachefs: Factor out two_state_shared_lock

We have a unique lock used for controlling adding to the pagecache: the
lock has two states, where both states are shared - the lock may be held
multiple times for either state - but not both states at the same time.

This is exactly what we need for nocow mode locking, so this patch pulls
it out of fs.c into its own file.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

1 files changed, 25 insertions, 25 deletions

diff --git a/fs/bcachefs/fs-io.c b/fs/bcachefs/fs-io.c
index 3c3fa95215ac..ab5b4e086e0a 100644
--- a/fs/bcachefs/fs-io.c
+++ b/fs/bcachefs/fs-io.c
@@ -751,25 +751,25 @@ vm_fault_t bch2_page_fault(struct vm_fault *vmf)
 	if (fdm > mapping) {
 		struct bch_inode_info *fdm_host = to_bch_ei(fdm->host);
 
-		if (bch2_pagecache_add_tryget(&inode->ei_pagecache_lock))
+		if (bch2_pagecache_add_tryget(inode))
 			goto got_lock;
 
-		bch2_pagecache_block_put(&fdm_host->ei_pagecache_lock);
+		bch2_pagecache_block_put(fdm_host);
 
-		bch2_pagecache_add_get(&inode->ei_pagecache_lock);
-		bch2_pagecache_add_put(&inode->ei_pagecache_lock);
+		bch2_pagecache_add_get(inode);
+		bch2_pagecache_add_put(inode);
 
-		bch2_pagecache_block_get(&fdm_host->ei_pagecache_lock);
+		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->ei_pagecache_lock);
+	bch2_pagecache_add_get(inode);
 got_lock:
 	ret = filemap_fault(vmf);
-	bch2_pagecache_add_put(&inode->ei_pagecache_lock);
+	bch2_pagecache_add_put(inode);
 
 	return ret;
 }
@@ -797,7 +797,7 @@ vm_fault_t bch2_page_mkwrite(struct vm_fault *vmf)
 	 * a write_invalidate_inode_pages_range() that works without dropping
 	 * page lock before invalidating page
 	 */
-	bch2_pagecache_add_get(&inode->ei_pagecache_lock);
+	bch2_pagecache_add_get(inode);
 
 	lock_page(page);
 	isize = i_size_read(&inode->v);
@@ -830,7 +830,7 @@ vm_fault_t bch2_page_mkwrite(struct vm_fault *vmf)
 	wait_for_stable_page(page);
 	ret = VM_FAULT_LOCKED;
 out:
-	bch2_pagecache_add_put(&inode->ei_pagecache_lock);
+	bch2_pagecache_add_put(inode);
 	sb_end_pagefault(inode->v.i_sb);
 
 	return ret;
@@ -1098,7 +1098,7 @@ void bch2_readahead(struct readahead_control *ractl)
 
 	bch2_trans_init(&trans, c, 0, 0);
 
-	bch2_pagecache_add_get(&inode->ei_pagecache_lock);
+	bch2_pagecache_add_get(inode);
 
 	while ((page = readpage_iter_next(&readpages_iter))) {
 		pgoff_t index = readpages_iter.offset + readpages_iter.idx;
@@ -1121,7 +1121,7 @@ void bch2_readahead(struct readahead_control *ractl)
 			   &readpages_iter);
 	}
 
-	bch2_pagecache_add_put(&inode->ei_pagecache_lock);
+	bch2_pagecache_add_put(inode);
 
 	bch2_trans_exit(&trans);
 	kfree(readpages_iter.pages);
@@ -1483,7 +1483,7 @@ int bch2_write_begin(struct file *file, struct address_space *mapping,
 	bch2_page_reservation_init(c, inode, res);
 	*fsdata = res;
 
-	bch2_pagecache_add_get(&inode->ei_pagecache_lock);
+	bch2_pagecache_add_get(inode);
 
 	page = grab_cache_page_write_begin(mapping, index);
 	if (!page)
@@ -1540,7 +1540,7 @@ err:
 	put_page(page);
 	*pagep = NULL;
 err_unlock:
-	bch2_pagecache_add_put(&inode->ei_pagecache_lock);
+	bch2_pagecache_add_put(inode);
 	kfree(res);
 	*fsdata = NULL;
 	return bch2_err_class(ret);
@@ -1584,7 +1584,7 @@ int bch2_write_end(struct file *file, struct address_space *mapping,
 
 	unlock_page(page);
 	put_page(page);
-	bch2_pagecache_add_put(&inode->ei_pagecache_lock);
+	bch2_pagecache_add_put(inode);
 
 	bch2_page_reservation_put(c, inode, res);
 	kfree(res);
@@ -1753,7 +1753,7 @@ static ssize_t bch2_buffered_write(struct kiocb *iocb, struct iov_iter *iter)
 	ssize_t written = 0;
 	int ret = 0;
 
-	bch2_pagecache_add_get(&inode->ei_pagecache_lock);
+	bch2_pagecache_add_get(inode);
 
 	do {
 		unsigned offset = pos & (PAGE_SIZE - 1);
@@ -1811,7 +1811,7 @@ again:
 		balance_dirty_pages_ratelimited(mapping);
 	} while (iov_iter_count(iter));
 
-	bch2_pagecache_add_put(&inode->ei_pagecache_lock);
+	bch2_pagecache_add_put(inode);
 
 	return written ? written : ret;
 }
@@ -1991,9 +1991,9 @@ ssize_t bch2_read_iter(struct kiocb *iocb, struct iov_iter *iter)
 		if (ret >= 0)
 			iocb->ki_pos += ret;
 	} else {
-		bch2_pagecache_add_get(&inode->ei_pagecache_lock);
+		bch2_pagecache_add_get(inode);
 		ret = generic_file_read_iter(iocb, iter);
-		bch2_pagecache_add_put(&inode->ei_pagecache_lock);
+		bch2_pagecache_add_put(inode);
 	}
 out:
 	return bch2_err_class(ret);
@@ -2149,7 +2149,7 @@ static __always_inline long bch2_dio_write_done(struct dio_write *dio)
 			return -EIOCBQUEUED;
 	}
 
-	bch2_pagecache_block_put(&inode->ei_pagecache_lock);
+	bch2_pagecache_block_put(inode);
 	bch2_quota_reservation_put(c, inode, &dio->quota_res);
 
 	if (dio->free_iov)
@@ -2357,7 +2357,7 @@ ssize_t bch2_direct_write(struct kiocb *req, struct iov_iter *iter)
 		goto err;
 
 	inode_dio_begin(&inode->v);
-	bch2_pagecache_block_get(&inode->ei_pagecache_lock);
+	bch2_pagecache_block_get(inode);
 
 	extending = req->ki_pos + iter->count > inode->v.i_size;
 	if (!extending) {
@@ -2403,7 +2403,7 @@ err:
 		inode_unlock(&inode->v);
 	return ret;
 err_put_bio:
-	bch2_pagecache_block_put(&inode->ei_pagecache_lock);
+	bch2_pagecache_block_put(inode);
 	bch2_quota_reservation_put(c, inode, &dio->quota_res);
 	bio_put(bio);
 	inode_dio_end(&inode->v);
@@ -2704,7 +2704,7 @@ int bch2_truncate(struct mnt_idmap *idmap,
 	}
 
 	inode_dio_wait(&inode->v);
-	bch2_pagecache_block_get(&inode->ei_pagecache_lock);
+	bch2_pagecache_block_get(inode);
 
 	ret = bch2_inode_find_by_inum(c, inode_inum(inode), &inode_u);
 	if (ret)
@@ -2783,7 +2783,7 @@ int bch2_truncate(struct mnt_idmap *idmap,
 
 	ret = bch2_setattr_nonsize(idmap, inode, iattr);
 err:
-	bch2_pagecache_block_put(&inode->ei_pagecache_lock);
+	bch2_pagecache_block_put(inode);
 	return bch2_err_class(ret);
 }
 
@@ -3195,7 +3195,7 @@ long bch2_fallocate_dispatch(struct file *file, int mode,
 
 	inode_lock(&inode->v);
 	inode_dio_wait(&inode->v);
-	bch2_pagecache_block_get(&inode->ei_pagecache_lock);
+	bch2_pagecache_block_get(inode);
 
 	ret = file_modified(file);
 	if (ret)
@@ -3212,7 +3212,7 @@ long bch2_fallocate_dispatch(struct file *file, int mode,
 	else
 		ret = -EOPNOTSUPP;
 err:
-	bch2_pagecache_block_put(&inode->ei_pagecache_lock);
+	bch2_pagecache_block_put(inode);
 	inode_unlock(&inode->v);
 	percpu_ref_put(&c->writes);