1 files changed, 79 insertions, 75 deletions

diff --git a/fs/hostfs/hostfs_kern.c b/fs/hostfs/hostfs_kern.c
index 6d1cf2436ead..51d26aa2b93e 100644
--- a/fs/hostfs/hostfs_kern.c
+++ b/fs/hostfs/hostfs_kern.c
@@ -33,6 +33,7 @@ struct hostfs_inode_info {
 	struct inode vfs_inode;
 	struct mutex open_mutex;
 	dev_t dev;
+	struct hostfs_timespec btime;
 };
 
 static inline struct hostfs_inode_info *HOSTFS_I(struct inode *inode)
@@ -57,6 +58,7 @@ static int __init hostfs_args(char *options, int *add)
 {
 	char *ptr;
 
+	*add = 0;
 	ptr = strchr(options, ',');
 	if (ptr != NULL)
 		*ptr++ = '\0';
@@ -94,32 +96,17 @@ __uml_setup("hostfs=", hostfs_args,
 static char *__dentry_name(struct dentry *dentry, char *name)
 {
 	char *p = dentry_path_raw(dentry, name, PATH_MAX);
-	char *root;
-	size_t len;
-	struct hostfs_fs_info *fsi;
-
-	fsi = dentry->d_sb->s_fs_info;
-	root = fsi->host_root_path;
-	len = strlen(root);
-	if (IS_ERR(p)) {
-		__putname(name);
-		return NULL;
-	}
-
-	/*
-	 * This function relies on the fact that dentry_path_raw() will place
-	 * the path name at the end of the provided buffer.
-	 */
-	BUG_ON(p + strlen(p) + 1 != name + PATH_MAX);
+	struct hostfs_fs_info *fsi = dentry->d_sb->s_fs_info;
+	char *root = fsi->host_root_path;
+	size_t len = strlen(root);
 
-	strscpy(name, root, PATH_MAX);
-	if (len > p - name) {
+	if (IS_ERR(p) || len > p - name) {
 		__putname(name);
 		return NULL;
 	}
 
-	if (p > name + len)
-		strcpy(name + len, p);
+	memcpy(name, root, len);
+	memmove(name + len, p, name + PATH_MAX - p);
 
 	return name;
 }
@@ -274,7 +261,7 @@ static int hostfs_show_options(struct seq_file *seq, struct dentry *root)
 static const struct super_operations hostfs_sbops = {
 	.alloc_inode	= hostfs_alloc_inode,
 	.free_inode	= hostfs_free_inode,
-	.drop_inode	= generic_delete_inode,
+	.drop_inode	= inode_just_drop,
 	.evict_inode	= hostfs_evict_inode,
 	.statfs		= hostfs_statfs,
 	.show_options	= hostfs_show_options,
@@ -395,7 +382,7 @@ static const struct file_operations hostfs_file_fops = {
 	.splice_write	= iter_file_splice_write,
 	.read_iter	= generic_file_read_iter,
 	.write_iter	= generic_file_write_iter,
-	.mmap		= generic_file_mmap,
+	.mmap_prepare	= generic_file_mmap_prepare,
 	.open		= hostfs_open,
 	.release	= hostfs_file_release,
 	.fsync		= hostfs_fsync,
@@ -409,38 +396,33 @@ static const struct file_operations hostfs_dir_fops = {
 	.fsync		= hostfs_fsync,
 };
 
-static int hostfs_writepage(struct page *page, struct writeback_control *wbc)
+static int hostfs_writepages(struct address_space *mapping,
+		struct writeback_control *wbc)
 {
-	struct address_space *mapping = page->mapping;
 	struct inode *inode = mapping->host;
-	char *buffer;
-	loff_t base = page_offset(page);
-	int count = PAGE_SIZE;
-	int end_index = inode->i_size >> PAGE_SHIFT;
-	int err;
-
-	if (page->index >= end_index)
-		count = inode->i_size & (PAGE_SIZE-1);
-
-	buffer = kmap_local_page(page);
-
-	err = write_file(HOSTFS_I(inode)->fd, &base, buffer, count);
-	if (err != count) {
-		if (err >= 0)
-			err = -EIO;
-		mapping_set_error(mapping, err);
-		goto out;
+	struct folio *folio = NULL;
+	loff_t i_size = i_size_read(inode);
+	int err = 0;
+
+	while ((folio = writeback_iter(mapping, wbc, folio, &err))) {
+		loff_t pos = folio_pos(folio);
+		size_t count = folio_size(folio);
+		char *buffer;
+		int ret;
+
+		if (count > i_size - pos)
+			count = i_size - pos;
+
+		buffer = kmap_local_folio(folio, 0);
+		ret = write_file(HOSTFS_I(inode)->fd, &pos, buffer, count);
+		kunmap_local(buffer);
+		folio_unlock(folio);
+		if (ret != count) {
+			err = ret < 0 ? ret : -EIO;
+			mapping_set_error(mapping, err);
+		}
 	}
 
-	if (base > inode->i_size)
-		inode->i_size = base;
-
-	err = 0;
-
- out:
-	kunmap_local(buffer);
-	unlock_page(page);
-
 	return err;
 }
 
@@ -463,7 +445,8 @@ static int hostfs_read_folio(struct file *file, struct folio *folio)
 	return ret;
 }
 
-static int hostfs_write_begin(struct file *file, struct address_space *mapping,
+static int hostfs_write_begin(const struct kiocb *iocb,
+			      struct address_space *mapping,
 			      loff_t pos, unsigned len,
 			      struct folio **foliop, void **fsdata)
 {
@@ -471,12 +454,13 @@ static int hostfs_write_begin(struct file *file, struct address_space *mapping,
 
 	*foliop = __filemap_get_folio(mapping, index, FGP_WRITEBEGIN,
 			mapping_gfp_mask(mapping));
-	if (!*foliop)
-		return -ENOMEM;
+	if (IS_ERR(*foliop))
+		return PTR_ERR(*foliop);
 	return 0;
 }
 
-static int hostfs_write_end(struct file *file, struct address_space *mapping,
+static int hostfs_write_end(const struct kiocb *iocb,
+			    struct address_space *mapping,
 			    loff_t pos, unsigned len, unsigned copied,
 			    struct folio *folio, void *fsdata)
 {
@@ -486,7 +470,7 @@ static int hostfs_write_end(struct file *file, struct address_space *mapping,
 	int err;
 
 	buffer = kmap_local_folio(folio, from);
-	err = write_file(FILE_HOSTFS_I(file)->fd, &pos, buffer, copied);
+	err = write_file(FILE_HOSTFS_I(iocb->ki_filp)->fd, &pos, buffer, copied);
 	kunmap_local(buffer);
 
 	if (!folio_test_uptodate(folio) && err == folio_size(folio))
@@ -505,11 +489,12 @@ static int hostfs_write_end(struct file *file, struct address_space *mapping,
 }
 
 static const struct address_space_operations hostfs_aops = {
-	.writepage 	= hostfs_writepage,
+	.writepages 	= hostfs_writepages,
 	.read_folio	= hostfs_read_folio,
 	.dirty_folio	= filemap_dirty_folio,
 	.write_begin	= hostfs_write_begin,
 	.write_end	= hostfs_write_end,
+	.migrate_folio	= filemap_migrate_folio,
 };
 
 static int hostfs_inode_update(struct inode *ino, const struct hostfs_stat *st)
@@ -565,6 +550,7 @@ static int hostfs_inode_set(struct inode *ino, void *data)
 	}
 
 	HOSTFS_I(ino)->dev = dev;
+	HOSTFS_I(ino)->btime = st->btime;
 	ino->i_ino = st->ino;
 	ino->i_mode = st->mode;
 	return hostfs_inode_update(ino, st);
@@ -575,7 +561,10 @@ static int hostfs_inode_test(struct inode *inode, void *data)
 	const struct hostfs_stat *st = data;
 	dev_t dev = MKDEV(st->dev.maj, st->dev.min);
 
-	return inode->i_ino == st->ino && HOSTFS_I(inode)->dev == dev;
+	return inode->i_ino == st->ino && HOSTFS_I(inode)->dev == dev &&
+	       (inode->i_mode & S_IFMT) == (st->mode & S_IFMT) &&
+	       HOSTFS_I(inode)->btime.tv_sec == st->btime.tv_sec &&
+	       HOSTFS_I(inode)->btime.tv_nsec == st->btime.tv_nsec;
 }
 
 static struct inode *hostfs_iget(struct super_block *sb, char *name)
@@ -592,7 +581,7 @@ static struct inode *hostfs_iget(struct super_block *sb, char *name)
 	if (!inode)
 		return ERR_PTR(-ENOMEM);
 
-	if (inode->i_state & I_NEW) {
+	if (inode_state_read_once(inode) & I_NEW) {
 		unlock_new_inode(inode);
 	} else {
 		spin_lock(&inode->i_lock);
@@ -697,17 +686,25 @@ static int hostfs_symlink(struct mnt_idmap *idmap, struct inode *ino,
 	return err;
 }
 
-static int hostfs_mkdir(struct mnt_idmap *idmap, struct inode *ino,
-			struct dentry *dentry, umode_t mode)
+static struct dentry *hostfs_mkdir(struct mnt_idmap *idmap, struct inode *ino,
+				   struct dentry *dentry, umode_t mode)
 {
+	struct inode *inode;
 	char *file;
 	int err;
 
 	if ((file = dentry_name(dentry)) == NULL)
-		return -ENOMEM;
+		return ERR_PTR(-ENOMEM);
 	err = do_mkdir(file, mode);
+	if (err) {
+		dentry = ERR_PTR(err);
+	} else {
+		inode = hostfs_iget(dentry->d_sb, file);
+		d_drop(dentry);
+		dentry = d_splice_alias(inode, dentry);
+	}
 	__putname(file);
-	return err;
+	return dentry;
 }
 
 static int hostfs_rmdir(struct inode *ino, struct dentry *dentry)
@@ -938,7 +935,7 @@ static int hostfs_fill_super(struct super_block *sb, struct fs_context *fc)
 	sb->s_blocksize_bits = 10;
 	sb->s_magic = HOSTFS_SUPER_MAGIC;
 	sb->s_op = &hostfs_sbops;
-	sb->s_d_op = &simple_dentry_operations;
+	sb->s_d_flags = DCACHE_DONTCACHE;
 	sb->s_maxbytes = MAX_LFS_FILESIZE;
 	err = super_setup_bdi(sb);
 	if (err)
@@ -982,7 +979,7 @@ static int hostfs_parse_param(struct fs_context *fc, struct fs_parameter *param)
 {
 	struct hostfs_fs_info *fsi = fc->s_fs_info;
 	struct fs_parse_result result;
-	char *host_root;
+	char *host_root, *tmp_root;
 	int opt;
 
 	opt = fs_parse(fc, hostfs_param_specs, param, &result);
@@ -993,11 +990,13 @@ static int hostfs_parse_param(struct fs_context *fc, struct fs_parameter *param)
 	case Opt_hostfs:
 		host_root = param->string;
 		if (!*host_root)
-			host_root = "";
-		fsi->host_root_path =
-			kasprintf(GFP_KERNEL, "%s/%s", root_ino, host_root);
-		if (fsi->host_root_path == NULL)
+			break;
+		tmp_root = kasprintf(GFP_KERNEL, "%s%s",
+				     fsi->host_root_path, host_root);
+		if (!tmp_root)
 			return -ENOMEM;
+		kfree(fsi->host_root_path);
+		fsi->host_root_path = tmp_root;
 		break;
 	}
 
@@ -1007,17 +1006,17 @@ static int hostfs_parse_param(struct fs_context *fc, struct fs_parameter *param)
 static int hostfs_parse_monolithic(struct fs_context *fc, void *data)
 {
 	struct hostfs_fs_info *fsi = fc->s_fs_info;
-	char *host_root = (char *)data;
+	char *tmp_root, *host_root = (char *)data;
 
 	/* NULL is printed as '(null)' by printf(): avoid that. */
 	if (host_root == NULL)
-		host_root = "";
+		return 0;
 
-	fsi->host_root_path =
-		kasprintf(GFP_KERNEL, "%s/%s", root_ino, host_root);
-	if (fsi->host_root_path == NULL)
+	tmp_root = kasprintf(GFP_KERNEL, "%s%s", fsi->host_root_path, host_root);
+	if (!tmp_root)
 		return -ENOMEM;
-
+	kfree(fsi->host_root_path);
+	fsi->host_root_path = tmp_root;
 	return 0;
 }
 
@@ -1052,6 +1051,11 @@ static int hostfs_init_fs_context(struct fs_context *fc)
 	if (!fsi)
 		return -ENOMEM;
 
+	fsi->host_root_path = kasprintf(GFP_KERNEL, "%s/", root_ino);
+	if (!fsi->host_root_path) {
+		kfree(fsi);
+		return -ENOMEM;
+	}
 	fc->s_fs_info = fsi;
 	fc->ops = &hostfs_context_ops;
 	return 0;