Merge patch series "fs: exfat: Flush node before put in read() callback"

This series from Marek Vasut <marex@denx.de> includes a number of fixes
to the exFAT filesystem support that he recently added.

Link: https://lore.kernel.org/r/20250413085740.5953-1-marex@denx.de

fs/exfat/io.c

@@ -597,15 +597,13 @@ ssize_t exfat_generic_pwrite(struct exfat* ef, struct exfat_node* node,
 }
 
 #ifdef __UBOOT__
+#define PATH_MAX FS_DIRENT_NAME_LEN
+
 struct exfat_dir_stream {
+	char dirname[PATH_MAX];
 	struct fs_dir_stream fs_dirs;
 	struct fs_dirent dirent;
-
-	struct exfat_node* node;
-	struct exfat_iterator it;
-	/* State tracker flags for emulated . and .. dirents */
-	bool dot;
-	bool dotdot;
+	int offset;
 };
 
 int exfat_fs_probe(struct blk_desc *fs_dev_desc,
@@ -626,8 +624,6 @@ error:
 	return ret;
 }
 
-#define PATH_MAX FS_DIRENT_NAME_LEN
-
 /* Adapted from uclibc 1.0.35 */
 static char *exfat_realpath(const char *path, char got_path[])
 {
@@ -721,31 +717,31 @@ int exfat_lookup_realpath(struct exfat* ef, struct exfat_node** node,
 int exfat_fs_opendir(const char *filename, struct fs_dir_stream **dirsp)
 {
 	struct exfat_dir_stream *dirs;
+	struct exfat_node *dnode;
 	int err;
 
+	err = exfat_lookup_realpath(&ctxt.ef, &dnode, filename);
+	if (err)
+		return err;
+
+	if (!(dnode->attrib & EXFAT_ATTRIB_DIR))
+		err = -ENOTDIR;
+
+	exfat_put_node(&ctxt.ef, dnode);
+
+	if (err)
+		return err;
+
 	dirs = calloc(1, sizeof(*dirs));
 	if (!dirs)
 		return -ENOMEM;
 
-	err = exfat_lookup_realpath(&ctxt.ef, &dirs->node, filename);
-	if (err)
-		goto err_out;
-
-	if (!(dirs->node->attrib & EXFAT_ATTRIB_DIR)) {
-		err = -ENOTDIR;
-		goto err_out;
-	}
-
-	err = exfat_opendir(&ctxt.ef, dirs->node, &dirs->it);
-	if (err)
-		goto err_out;
+	strcpy(dirs->dirname, filename);
+	dirs->offset = -1;
 
 	*dirsp = &dirs->fs_dirs;
 
 	return 0;
-err_out:
-	free(dirs);
-	return err;
 }
 
 int exfat_fs_readdir(struct fs_dir_stream *fs_dirs, struct fs_dirent **dentp)
@@ -753,32 +749,49 @@ int exfat_fs_readdir(struct fs_dir_stream *fs_dirs, struct fs_dirent **dentp)
 	struct exfat_dir_stream *dirs =
 		container_of(fs_dirs, struct exfat_dir_stream, fs_dirs);
 	struct fs_dirent *dent = &dirs->dirent;
-	struct exfat_node* node;
+	struct exfat_node *dnode, *node;
+	struct exfat_iterator it;
+	int offset = 0;
+	int err;
+
+	err = exfat_lookup_realpath(&ctxt.ef, &dnode, dirs->dirname);
+	if (err)
+		return err;
+
+	if (!(dnode->attrib & EXFAT_ATTRIB_DIR)) {
+		err = -ENOTDIR;
+		goto err_out;
+	}
 
 	/* Emulate current directory ./ */
-	if (!dirs->dot) {
-		dirs->dot = true;
+	if (dirs->offset == -1) {
+		dirs->offset++;
 		snprintf(dent->name, FS_DIRENT_NAME_LEN, ".");
 		dent->type = FS_DT_DIR;
 		*dentp = dent;
-		return 0;
+		goto err_out;
 	}
 
 	/* Emulate parent directory ../ */
-	if (!dirs->dotdot) {
-		dirs->dotdot = true;
+	if (dirs->offset == 0) {
+		dirs->offset++;
 		snprintf(dent->name, FS_DIRENT_NAME_LEN, "..");
 		dent->type = FS_DT_DIR;
 		*dentp = dent;
-		return 0;
+		goto err_out;
 	}
 
+	err = exfat_opendir(&ctxt.ef, dnode, &it);
+	if (err)
+		goto err_out;
+
+	*dentp = NULL;
+
 	/* Read actual directory content */
-	node = exfat_readdir(&dirs->it);
-	if (!node) {	/* No more content, reset . and .. emulation */
-		dirs->dot = false;
-		dirs->dotdot = false;
-		return 1;
+	while ((node = exfat_readdir(&it))) {
+		if (dirs->offset != ++offset) {
+			exfat_put_node(&ctxt.ef, node);
+			continue;
 		}
 
 		exfat_get_name(node, dent->name);
@@ -788,15 +801,25 @@ int exfat_fs_readdir(struct fs_dir_stream *fs_dirs, struct fs_dirent **dentp)
 			dent->type = FS_DT_REG;
 			dent->size = node->size;
 		}
-
+		exfat_put_node(&ctxt.ef, node);
 		*dentp = dent;
+		dirs->offset++;
+		break;
+	}
 
-	return 0;
+	exfat_closedir(&ctxt.ef, &it);
+
+err_out:
+	exfat_put_node(&ctxt.ef, dnode);
+	return err;
 }
 
 void exfat_fs_closedir(struct fs_dir_stream *fs_dirs)
 {
-	free(fs_dirs);
+	struct exfat_dir_stream *dirs =
+		container_of(fs_dirs, struct exfat_dir_stream, fs_dirs);
+
+	free(dirs);
 }
 
 int exfat_fs_ls(const char *dirname)
@@ -852,11 +875,11 @@ int exfat_fs_exists(const char *filename)
 
 	err = exfat_lookup_realpath(&ctxt.ef, &node, filename);
 	if (err)
-		return err;
+		return 0;
 
 	exfat_put_node(&ctxt.ef, node);
 
-	return 0;
+	return 1;
 }
 
 int exfat_fs_size(const char *filename, loff_t *size)
@@ -898,9 +921,7 @@ int exfat_fs_read(const char *filename, void *buf, loff_t offset, loff_t len,
 
 	*actread = sz;
 
-	exfat_put_node(&ctxt.ef, node);
-
-	return exfat_flush_node(&ctxt.ef, node);
+	err = exfat_flush_node(&ctxt.ef, node);
 exit:
 	exfat_put_node(&ctxt.ef, node);
 	return err;
@@ -992,6 +1013,11 @@ exit:
 	return err;
 }
 
+int exfat_fs_rename(const char *old_path, const char *new_path)
+{
+	return exfat_rename(&ctxt.ef, old_path, new_path);
+}
+
 void exfat_fs_close(void)
 {
 	exfat_unmount(&ctxt.ef);

fs/exfat/lookup.c

@@ -218,8 +218,9 @@ int exfat_split(struct exfat* ef, struct exfat_node** parent,
 		exfat_put_node(ef, *parent);
 		*parent = *node;
 	}
+#ifndef __UBOOT__
 	exfat_bug("impossible");
-#ifdef __UBOOT__
+#else
 	return 0;
 #endif
 }

fs/fs.c

@@ -401,6 +401,7 @@ static struct fstype_info fstypes[] = {
 		.ln = fs_ln_unsupported,
 		.unlink = exfat_fs_unlink,
 		.mkdir = exfat_fs_mkdir,
+		.rename = exfat_fs_rename,
 	},
 #endif
 	{

include/exfat.h

@@ -20,5 +20,6 @@ int exfat_fs_unlink(const char *filename);
 int exfat_fs_mkdir(const char *dirname);
 int exfat_fs_write(const char *filename, void *buf, loff_t offset,
 		   loff_t len, loff_t *actwrite);
+int exfat_fs_rename(const char *old_path, const char *new_path);
 
 #endif /* _EXFAT_H */

test/py/tests/test_fs/conftest.py

@@ -17,7 +17,7 @@ supported_fs_fat = ['fat12', 'fat16']
 supported_fs_mkdir = ['fat12', 'fat16', 'fat32', 'exfat', 'fs_generic']
 supported_fs_unlink = ['fat12', 'fat16', 'fat32', 'exfat', 'fs_generic']
 supported_fs_symlink = ['ext4']
-supported_fs_rename = ['fat12', 'fat16', 'fat32']
+supported_fs_rename = ['fat12', 'fat16', 'fat32', 'exfat', 'fs_generic']
 
 #
 # Filesystem test specific setup

test/py/tests/test_fs/test_basic.py

@@ -35,6 +35,19 @@ class TestFsBasic(object):
                 '%sls host 0:0 invalid_d' % fs_cmd_prefix)
             assert('' == output)
 
+        with ubman.log.section('Test Case 1c - test -e'):
+            # Test Case 1 - test -e
+            output = ubman.run_command_list([
+                'host bind 0 %s' % fs_img,
+                'test -e host 0:0 1MB.file && echo PASS'])
+            assert('PASS' in ''.join(output))
+
+        with ubman.log.section('Test Case 1d - test -e (invalid file)'):
+            # In addition, test with a nonexistent file to see if we crash.
+            output = ubman.run_command(
+                'test -e host 0:0 2MB.file || echo PASS')
+            assert('PASS' in ''.join(output))
+
     def test_fs2(self, ubman, fs_obj_basic):
         """
         Test Case 2 - size command for a small file