[PATCH v2 13/14] f2fs: allow large folio support to writeable files

[Nanzhe Zhao]

Now we make all write path support large folios,
so we open permission to let writeable file set
large folio mapping.

Keep fs-layer encrypted files excluded unless inline encryption is
enabled, since f2fs_encrypt_one_page() still encrypts one PAGE_SIZE
page and cannot handle large folios.

Inline files are allowed as well; their index #0 folio stays order-0
(see the large folio write path), so the existing inline read/convert
paths are not affected and large folios are used from the second folio
on.

Signed-off-by: Nanzhe Zhao <zhaonanzhe@xxxxxxxxxx>
---
 fs/f2fs/data.c   |  2 +-
 fs/f2fs/f2fs.h   | 17 +++++++++++++++++
 fs/f2fs/file.c   | 16 ----------------
 fs/f2fs/inline.c |  6 ++++++
 fs/f2fs/inode.c  |  4 +---
 fs/f2fs/namei.c  |  1 +
 6 files changed, 26 insertions(+), 20 deletions(-)

diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
index 295424f2ade5..c9dba8d0ad3d 100644
--- a/fs/f2fs/data.c
+++ b/fs/f2fs/data.c
@@ -2941,7 +2941,7 @@ static int f2fs_read_data_large_folio(struct inode *inode,
 	int ret = 0;
 	bool folio_in_bio = false;
 
-	if (!IS_IMMUTABLE(inode) || f2fs_compressed_file(inode)) {
+	if (f2fs_compressed_file(inode)) {
 		if (folio)
 			folio_unlock(folio);
 		return -EOPNOTSUPP;
diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index d99a812810d3..d608376b1456 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -5251,6 +5251,23 @@ static inline bool f2fs_quota_file(struct f2fs_sb_info *sbi, nid_t ino)
 	return false;
 }
 
+static inline void f2fs_mapping_set_large_folio(struct inode *inode)
+{
+	if (!S_ISREG(inode->i_mode) ||
+	    f2fs_compressed_file(inode) ||
+	    f2fs_quota_file(F2FS_I_SB(inode), inode->i_ino))
+		return;
+
+	/*
+	 * Keep the folio order range at 0 as a transitional step; large
+	 * folios will be enabled once the whole write path is audited.
+	 */
+	if (IS_IMMUTABLE(inode))
+		mapping_set_folio_min_order(inode->i_mapping, 0);
+	else
+		mapping_set_folio_order_range(inode->i_mapping, 0, 0);
+}
+
 static inline bool f2fs_block_unit_discard(struct f2fs_sb_info *sbi)
 {
 	return F2FS_OPTION(sbi).discard_unit == DISCARD_UNIT_BLOCK;
diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
index a36d243ca305..db71cadefabd 100644
--- a/fs/f2fs/file.c
+++ b/fs/f2fs/file.c
@@ -162,17 +162,6 @@ static vm_fault_t f2fs_vm_page_mkwrite(struct vm_fault *vmf)
 	int err = 0;
 	vm_fault_t ret;
 
-	/*
-	 * We only support large folio on the read case.
-	 * Don't make any dirty pages.
-	 */
-	if (unlikely(IS_IMMUTABLE(inode)) ||
-	    mapping_large_folio_support(inode->i_mapping)) {
-		f2fs_err(sbi, "Not expected: immutable: %d large_folio: %d",
-				IS_IMMUTABLE(inode),
-				mapping_large_folio_support(inode->i_mapping));
-		return VM_FAULT_SIGBUS;
-	}
 
 	if (is_inode_flag_set(inode, FI_COMPRESS_RELEASED)) {
 		err = -EIO;
@@ -712,9 +701,6 @@ static int f2fs_file_open(struct inode *inode, struct file *filp)
 	if (!f2fs_is_compress_backend_ready(inode))
 		return -EOPNOTSUPP;
 
-	if (mapping_large_folio_support(inode->i_mapping) &&
-	    filp->f_mode & FMODE_WRITE)
-		return -EOPNOTSUPP;
 
 	err = fsverity_file_open(inode, filp);
 	if (err)
@@ -1186,8 +1172,6 @@ int f2fs_setattr(struct mnt_idmap *idmap, struct dentry *dentry,
 		return -EPERM;
 
 	if ((attr->ia_valid & ATTR_SIZE)) {
-		if (mapping_large_folio_support(inode->i_mapping))
-			return -EOPNOTSUPP;
 		if (IS_DEVICE_ALIASING(inode))
 			return -EPERM;
 		if (!f2fs_is_compress_backend_ready(inode))
diff --git a/fs/f2fs/inline.c b/fs/f2fs/inline.c
index 8db083b545bc..51cc2e6c0284 100644
--- a/fs/f2fs/inline.c
+++ b/fs/f2fs/inline.c
@@ -238,6 +238,12 @@ int f2fs_convert_inline_inode(struct inode *inode)
 	if (IS_ERR(folio))
 		return PTR_ERR(folio);
 
+	/*
+	 * Inline data is only supported in an order-0 index #0 folio; the
+	 * inline write and mmap fault paths never request a larger order.
+	 */
+	f2fs_bug_on(sbi, folio_test_large(folio));
+
 	f2fs_lock_op(sbi, &lc);
 
 	ifolio = f2fs_get_inode_folio(sbi, inode->i_ino);
diff --git a/fs/f2fs/inode.c b/fs/f2fs/inode.c
index 24205a35be04..c8a4c62c9927 100644
--- a/fs/f2fs/inode.c
+++ b/fs/f2fs/inode.c
@@ -643,9 +643,7 @@ struct inode *f2fs_iget(struct super_block *sb, unsigned long ino)
 		inode->i_op = &f2fs_file_inode_operations;
 		inode->i_fop = &f2fs_file_operations;
 		inode->i_mapping->a_ops = &f2fs_dblock_aops;
-		if (IS_IMMUTABLE(inode) && !f2fs_compressed_file(inode) &&
-		    !f2fs_quota_file(sbi, inode->i_ino))
-			mapping_set_folio_min_order(inode->i_mapping, 0);
+		f2fs_mapping_set_large_folio(inode);
 	} else if (S_ISDIR(inode->i_mode)) {
 		inode->i_op = &f2fs_dir_inode_operations;
 		inode->i_fop = &f2fs_dir_operations;
diff --git a/fs/f2fs/namei.c b/fs/f2fs/namei.c
index ff86ee07290d..9d0cec72aacc 100644
--- a/fs/f2fs/namei.c
+++ b/fs/f2fs/namei.c
@@ -341,6 +341,7 @@ static struct inode *f2fs_new_inode(struct mnt_idmap *idmap,
 	f2fs_set_inode_flags(inode);
 
 	f2fs_init_extent_tree(inode);
+	f2fs_mapping_set_large_folio(inode);
 
 	trace_f2fs_new_inode(inode, 0);
 	return inode;
-- 
2.43.0