Unverified Commit f9d8c3c4 authored by Christian Brauner's avatar Christian Brauner
Browse files

block2mtd: port device access to files 

Link: https://lore.kernel.org/r/20240123-vfs-bdev-file-v2-14-adbd023e19cc@kernel.org


Reviewed-by: default avatarJan Kara <jack@suse.cz>
Signed-off-by: default avatarChristian Brauner <brauner@kernel.org>
parent 3789fb87

drivers/mtd/devices/block2mtd.c

+21 −25
Original line number Diff line number Diff line
@@ -37,7 +37,7 @@ 
/* Info for the block device */

struct block2mtd_dev {

	struct list_head list;

	struct bdev_handle *bdev_handle;

	struct file *bdev_file;

	struct mtd_info mtd;

	struct mutex write_mutex;

};
@@ -55,8 +55,7 @@ static struct page *page_read(struct address_space *mapping, pgoff_t index) 
/* erase a specified part of the device */

static int _block2mtd_erase(struct block2mtd_dev *dev, loff_t to, size_t len)

{

	struct address_space *mapping =

				dev->bdev_handle->bdev->bd_inode->i_mapping;

	struct address_space *mapping = dev->bdev_file->f_mapping;

	struct page *page;

	pgoff_t index = to >> PAGE_SHIFT;	// page index

	int pages = len >> PAGE_SHIFT;
@@ -106,8 +105,7 @@ static int block2mtd_read(struct mtd_info *mtd, loff_t from, size_t len, 
		size_t *retlen, u_char *buf)

{

	struct block2mtd_dev *dev = mtd->priv;

	struct address_space *mapping =

				dev->bdev_handle->bdev->bd_inode->i_mapping;

	struct address_space *mapping = dev->bdev_file->f_mapping;

	struct page *page;

	pgoff_t index = from >> PAGE_SHIFT;

	int offset = from & (PAGE_SIZE-1);
@@ -142,8 +140,7 @@ static int _block2mtd_write(struct block2mtd_dev *dev, const u_char *buf, 
		loff_t to, size_t len, size_t *retlen)

{

	struct page *page;

	struct address_space *mapping =

				dev->bdev_handle->bdev->bd_inode->i_mapping;

	struct address_space *mapping = dev->bdev_file->f_mapping;

	pgoff_t index = to >> PAGE_SHIFT;	// page index

	int offset = to & ~PAGE_MASK;	// page offset

	int cpylen;
@@ -198,7 +195,7 @@ static int block2mtd_write(struct mtd_info *mtd, loff_t to, size_t len, 
static void block2mtd_sync(struct mtd_info *mtd)

{

	struct block2mtd_dev *dev = mtd->priv;

	sync_blockdev(dev->bdev_handle->bdev);

	sync_blockdev(file_bdev(dev->bdev_file));

	return;

}
@@ -210,10 +207,9 @@ static void block2mtd_free_device(struct block2mtd_dev *dev) 


	kfree(dev->mtd.name);



	if (dev->bdev_handle) {

		invalidate_mapping_pages(

			dev->bdev_handle->bdev->bd_inode->i_mapping, 0, -1);

		bdev_release(dev->bdev_handle);

	if (dev->bdev_file) {

		invalidate_mapping_pages(dev->bdev_file->f_mapping, 0, -1);

		fput(dev->bdev_file);

	}



	kfree(dev);
@@ -223,10 +219,10 @@ static void block2mtd_free_device(struct block2mtd_dev *dev) 
 * This function is marked __ref because it calls the __init marked

 * early_lookup_bdev when called from the early boot code.

 */

static struct bdev_handle __ref *mdtblock_early_get_bdev(const char *devname,

static struct file __ref *mdtblock_early_get_bdev(const char *devname,

		blk_mode_t mode, int timeout, struct block2mtd_dev *dev)

{

	struct bdev_handle *bdev_handle = ERR_PTR(-ENODEV);

	struct file *bdev_file = ERR_PTR(-ENODEV);

#ifndef MODULE

	int i;
@@ -234,7 +230,7 @@ static struct bdev_handle __ref *mdtblock_early_get_bdev(const char *devname, 
	 * We can't use early_lookup_bdev from a running system.

	 */

	if (system_state >= SYSTEM_RUNNING)

		return bdev_handle;

		return bdev_file;



	/*

	 * We might not have the root device mounted at this point.
@@ -253,20 +249,20 @@ static struct bdev_handle __ref *mdtblock_early_get_bdev(const char *devname, 
		wait_for_device_probe();



		if (!early_lookup_bdev(devname, &devt)) {

			bdev_handle = bdev_open_by_dev(devt, mode, dev, NULL);

			if (!IS_ERR(bdev_handle))

			bdev_file = bdev_file_open_by_dev(devt, mode, dev, NULL);

			if (!IS_ERR(bdev_file))

				break;

		}

	}

#endif

	return bdev_handle;

	return bdev_file;

}



static struct block2mtd_dev *add_device(char *devname, int erase_size,

		char *label, int timeout)

{

	const blk_mode_t mode = BLK_OPEN_READ | BLK_OPEN_WRITE;

	struct bdev_handle *bdev_handle;

	struct file *bdev_file;

	struct block_device *bdev;

	struct block2mtd_dev *dev;

	char *name;
@@ -279,16 +275,16 @@ static struct block2mtd_dev *add_device(char *devname, int erase_size, 
		return NULL;



	/* Get a handle on the device */

	bdev_handle = bdev_open_by_path(devname, mode, dev, NULL);

	if (IS_ERR(bdev_handle))

		bdev_handle = mdtblock_early_get_bdev(devname, mode, timeout,

	bdev_file = bdev_file_open_by_path(devname, mode, dev, NULL);

	if (IS_ERR(bdev_file))

		bdev_file = mdtblock_early_get_bdev(devname, mode, timeout,

						      dev);

	if (IS_ERR(bdev_handle)) {

	if (IS_ERR(bdev_file)) {

		pr_err("error: cannot open device %s\n", devname);

		goto err_free_block2mtd;

	}

	dev->bdev_handle = bdev_handle;

	bdev = bdev_handle->bdev;

	dev->bdev_file = bdev_file;

	bdev = file_bdev(bdev_file);



	if (MAJOR(bdev->bd_dev) == MTD_BLOCK_MAJOR) {

		pr_err("attempting to use an MTD device as a block device\n");