sandbox: block driver using host file/device as backing store
Provide a way to use any host file or device as a block device in U-Boot.
This can be used to provide filesystem access within U-Boot to an ext2
image file on the host, for example.
The support is plumbed into the filesystem and partition interfaces.
We don't want to print a message in the driver every time we find a missing
device. Pass the information back to the caller where a message can be printed
if desired.
Signed-off-by: Henrik Nordström <henrik@henriknordstrom.net>
Signed-off-by: Simon Glass <sjg@chromium.org>
- Removed change to part.c get_device_and_partition()
Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/drivers/block/sandbox.c b/drivers/block/sandbox.c
new file mode 100644
index 0000000..73f4c4a
--- /dev/null
+++ b/drivers/block/sandbox.c
@@ -0,0 +1,124 @@
+/*
+ * Copyright (C) 2013 Henrik Nordstrom <henrik@henriknordstrom.net>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#include <config.h>
+#include <common.h>
+#include <part.h>
+#include <os.h>
+#include <malloc.h>
+#include <sandboxblockdev.h>
+#include <asm/errno.h>
+
+static struct host_block_dev host_devices[CONFIG_HOST_MAX_DEVICES];
+
+static struct host_block_dev *find_host_device(int dev)
+{
+ if (dev >= 0 && dev < CONFIG_HOST_MAX_DEVICES)
+ return &host_devices[dev];
+
+ return NULL;
+}
+
+static unsigned long host_block_read(int dev, unsigned long start,
+ lbaint_t blkcnt, void *buffer)
+{
+ struct host_block_dev *host_dev = find_host_device(dev);
+
+ if (!host_dev)
+ return -1;
+ if (os_lseek(host_dev->fd,
+ start * host_dev->blk_dev.blksz,
+ OS_SEEK_SET) == -1) {
+ printf("ERROR: Invalid position\n");
+ return -1;
+ }
+ ssize_t len = os_read(host_dev->fd, buffer,
+ blkcnt * host_dev->blk_dev.blksz);
+ if (len >= 0)
+ return len / host_dev->blk_dev.blksz;
+ return -1;
+}
+
+static unsigned long host_block_write(int dev, unsigned long start,
+ lbaint_t blkcnt, const void *buffer)
+{
+ struct host_block_dev *host_dev = find_host_device(dev);
+ if (os_lseek(host_dev->fd,
+ start * host_dev->blk_dev.blksz,
+ OS_SEEK_SET) == -1) {
+ printf("ERROR: Invalid position\n");
+ return -1;
+ }
+ ssize_t len = os_write(host_dev->fd, buffer, blkcnt *
+ host_dev->blk_dev.blksz);
+ if (len >= 0)
+ return len / host_dev->blk_dev.blksz;
+ return -1;
+}
+
+int host_dev_bind(int dev, char *filename)
+{
+ struct host_block_dev *host_dev = find_host_device(dev);
+
+ if (!host_dev)
+ return -1;
+ if (host_dev->blk_dev.priv) {
+ os_close(host_dev->fd);
+ host_dev->blk_dev.priv = NULL;
+ }
+ if (host_dev->filename)
+ free(host_dev->filename);
+ if (filename && *filename) {
+ host_dev->filename = strdup(filename);
+ } else {
+ host_dev->filename = NULL;
+ return 0;
+ }
+
+ host_dev->fd = os_open(host_dev->filename, OS_O_RDWR);
+ if (host_dev->fd == -1) {
+ printf("Failed to access host backing file '%s'\n",
+ host_dev->filename);
+ return 1;
+ }
+
+ block_dev_desc_t *blk_dev = &host_dev->blk_dev;
+ blk_dev->if_type = IF_TYPE_HOST;
+ blk_dev->priv = host_dev;
+ blk_dev->blksz = 512;
+ blk_dev->lba = os_lseek(host_dev->fd, 0, OS_SEEK_END) / blk_dev->blksz;
+ blk_dev->block_read = host_block_read;
+ blk_dev->block_write = host_block_write;
+ blk_dev->dev = dev;
+ blk_dev->part_type = PART_TYPE_UNKNOWN;
+ init_part(blk_dev);
+
+ return 0;
+}
+
+int host_get_dev_err(int dev, block_dev_desc_t **blk_devp)
+{
+ struct host_block_dev *host_dev = find_host_device(dev);
+
+ if (!host_dev)
+ return -ENODEV;
+
+ if (!host_dev->blk_dev.priv)
+ return -ENOENT;
+
+ *blk_devp = &host_dev->blk_dev;
+ return 0;
+}
+
+block_dev_desc_t *host_get_dev(int dev)
+{
+ block_dev_desc_t *blk_dev;
+
+ if (host_get_dev_err(dev, &blk_dev))
+ return NULL;
+
+ return blk_dev;
+}