fs: rename and move block_page_mkwrite_return

block_page_mkwrite_return is neither block nor mkwrite specific, and
should not be under CONFIG_BLOCK.  Move it to mm.h and rename it to
vmf_fs_error.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Luis Chamberlain <mcgrof@kernel.org>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Christian Brauner <brauner@kernel.org>
Link: https://lore.kernel.org/r/20230801172201.1923299-3-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Author: Christoph Hellwig

fs/ext4/inode.c

@@ -6140,7 +6140,7 @@ vm_fault_t ext4_page_mkwrite(struct vm_fault *vmf)
 	if (err == -ENOSPC && ext4_should_retry_alloc(inode->i_sb, &retries))
 		goto retry_alloc;
 out_ret:
-	ret = block_page_mkwrite_return(err);
+	ret = vmf_fs_error(err);
 out:
 	filemap_invalidate_unlock_shared(mapping);
 	sb_end_pagefault(inode->i_sb);

fs/f2fs/file.c

@@ -159,7 +159,7 @@ static vm_fault_t f2fs_vm_page_mkwrite(struct vm_fault *vmf)
 
 	sb_end_pagefault(inode->i_sb);
 err:
-	return block_page_mkwrite_return(err);
+	return vmf_fs_error(err);
 }
 
 static const struct vm_operations_struct f2fs_file_vm_ops = {

fs/gfs2/file.c

@@ -432,7 +432,7 @@ static vm_fault_t gfs2_page_mkwrite(struct vm_fault *vmf)
 	gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh);
 	err = gfs2_glock_nq(&gh);
 	if (err) {
-		ret = block_page_mkwrite_return(err);
+		ret = vmf_fs_error(err);
 		goto out_uninit;
 	}
 
@@ -474,20 +474,20 @@ static vm_fault_t gfs2_page_mkwrite(struct vm_fault *vmf)
 
 	err = gfs2_rindex_update(sdp);
 	if (err) {
-		ret = block_page_mkwrite_return(err);
+		ret = vmf_fs_error(err);
 		goto out_unlock;
 	}
 
 	gfs2_write_calc_reserv(ip, length, &data_blocks, &ind_blocks);
 	ap.target = data_blocks + ind_blocks;
 	err = gfs2_quota_lock_check(ip, &ap);
 	if (err) {
-		ret = block_page_mkwrite_return(err);
+		ret = vmf_fs_error(err);
 		goto out_unlock;
 	}
 	err = gfs2_inplace_reserve(ip, &ap);
 	if (err) {
-		ret = block_page_mkwrite_return(err);
+		ret = vmf_fs_error(err);
 		goto out_quota_unlock;
 	}
 
@@ -500,15 +500,15 @@ static vm_fault_t gfs2_page_mkwrite(struct vm_fault *vmf)
 	}
 	err = gfs2_trans_begin(sdp, rblocks, 0);
 	if (err) {
-		ret = block_page_mkwrite_return(err);
+		ret = vmf_fs_error(err);
 		goto out_trans_fail;
 	}
 
 	/* Unstuff, if required, and allocate backing blocks for page */
 	if (gfs2_is_stuffed(ip)) {
 		err = gfs2_unstuff_dinode(ip);
 		if (err) {
-			ret = block_page_mkwrite_return(err);
+			ret = vmf_fs_error(err);
 			goto out_trans_end;
 		}
 	}
@@ -524,7 +524,7 @@ static vm_fault_t gfs2_page_mkwrite(struct vm_fault *vmf)
 
 	err = gfs2_allocate_page_backing(page, length);
 	if (err)
-		ret = block_page_mkwrite_return(err);
+		ret = vmf_fs_error(err);
 
 out_page_locked:
 	if (ret != VM_FAULT_LOCKED)
@@ -558,7 +558,7 @@ static vm_fault_t gfs2_fault(struct vm_fault *vmf)
 	gfs2_holder_init(ip->i_gl, LM_ST_SHARED, 0, &gh);
 	err = gfs2_glock_nq(&gh);
 	if (err) {
-		ret = block_page_mkwrite_return(err);
+		ret = vmf_fs_error(err);
 		goto out_uninit;
 	}
 	ret = filemap_fault(vmf);

fs/iomap/buffered-io.c

@@ -1286,7 +1286,7 @@ vm_fault_t iomap_page_mkwrite(struct vm_fault *vmf, const struct iomap_ops *ops)
 	return VM_FAULT_LOCKED;
 out_unlock:
 	folio_unlock(folio);
-	return block_page_mkwrite_return(ret);
+	return vmf_fs_error(ret);
 }
 EXPORT_SYMBOL_GPL(iomap_page_mkwrite);
 

fs/nilfs2/file.c

@@ -108,7 +108,7 @@ static vm_fault_t nilfs_page_mkwrite(struct vm_fault *vmf)
 	wait_for_stable_page(page);
  out:
 	sb_end_pagefault(inode->i_sb);
-	return block_page_mkwrite_return(ret);
+	return vmf_fs_error(ret);
 }
 
 static const struct vm_operations_struct nilfs_file_vm_ops = {

fs/udf/file.c

@@ -67,7 +67,7 @@ static vm_fault_t udf_page_mkwrite(struct vm_fault *vmf)
 		err = block_commit_write(page, 0, end);
 	if (err < 0) {
 		unlock_page(page);
-		ret = block_page_mkwrite_return(err);
+		ret = vmf_fs_error(err);
 		goto out_unlock;
 	}
 out_dirty:

include/linux/buffer_head.h

@@ -291,18 +291,6 @@ int generic_cont_expand_simple(struct inode *inode, loff_t size);
 int block_commit_write(struct page *page, unsigned from, unsigned to);
 int block_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf,
 				get_block_t get_block);
-/* Convert errno to return value from ->page_mkwrite() call */
-static inline vm_fault_t block_page_mkwrite_return(int err)
-{
-	if (err == 0)
-		return VM_FAULT_LOCKED;
-	if (err == -EFAULT || err == -EAGAIN)
-		return VM_FAULT_NOPAGE;
-	if (err == -ENOMEM)
-		return VM_FAULT_OOM;
-	/* -ENOSPC, -EDQUOT, -EIO ... */
-	return VM_FAULT_SIGBUS;
-}
 sector_t generic_block_bmap(struct address_space *, sector_t, get_block_t *);
 int block_truncate_page(struct address_space *, loff_t, get_block_t *);
 

include/linux/mm.h

@@ -3386,6 +3386,24 @@ static inline vm_fault_t vmf_error(int err)
 	return VM_FAULT_SIGBUS;
 }
 
+/*
+ * Convert errno to return value for ->page_mkwrite() calls.
+ *
+ * This should eventually be merged with vmf_error() above, but will need a
+ * careful audit of all vmf_error() callers.
+ */
+static inline vm_fault_t vmf_fs_error(int err)
+{
+	if (err == 0)
+		return VM_FAULT_LOCKED;
+	if (err == -EFAULT || err == -EAGAIN)
+		return VM_FAULT_NOPAGE;
+	if (err == -ENOMEM)
+		return VM_FAULT_OOM;
+	/* -ENOSPC, -EDQUOT, -EIO ... */
+	return VM_FAULT_SIGBUS;
+}
+
 struct page *follow_page(struct vm_area_struct *vma, unsigned long address,
 			 unsigned int foll_flags);