From 6eef6eac1fc137c97bf1993304ed83b8e483c80a Mon Sep 17 00:00:00 2001 From: Simon Glass Date: Sun, 1 May 2016 11:36:03 -0600 Subject: dm: blk: Add a legacy block interface There is quite a bit of duplicated common code related to block devices in the IDE and SCSI implementations. Create some helper functions that can be used to reduce the duplication. These rely on a linker list of interface-type drivers Signed-off-by: Simon Glass --- drivers/block/blk_legacy.c | 261 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 261 insertions(+) create mode 100644 drivers/block/blk_legacy.c (limited to 'drivers/block/blk_legacy.c') diff --git a/drivers/block/blk_legacy.c b/drivers/block/blk_legacy.c new file mode 100644 index 0000000..7b90a8a --- /dev/null +++ b/drivers/block/blk_legacy.c @@ -0,0 +1,261 @@ +/* + * Copyright (C) 2016 Google, Inc + * Written by Simon Glass + * + * SPDX-License-Identifier: GPL-2.0+ + */ + +#include +#include + +struct blk_driver *blk_driver_lookup_type(int if_type) +{ + struct blk_driver *drv = ll_entry_start(struct blk_driver, blk_driver); + const int n_ents = ll_entry_count(struct blk_driver, blk_driver); + struct blk_driver *entry; + + for (entry = drv; entry != drv + n_ents; entry++) { + if (if_type == entry->if_type) + return entry; + } + + /* Not found */ + return NULL; +} + +static struct blk_driver *blk_driver_lookup_typename(const char *if_typename) +{ + struct blk_driver *drv = ll_entry_start(struct blk_driver, blk_driver); + const int n_ents = ll_entry_count(struct blk_driver, blk_driver); + struct blk_driver *entry; + + for (entry = drv; entry != drv + n_ents; entry++) { + if (!strcmp(if_typename, entry->if_typename)) + return entry; + } + + /* Not found */ + return NULL; +} + +/** + * get_desc() - Get the block device descriptor for the given device number + * + * @drv: Legacy block driver + * @devnum: Device number (0 = first) + * @descp: Returns block device descriptor on success + * @return 0 on success, -ENODEV if there is no such device, -ENOSYS if the + * driver does not provide a way to find a device, or other -ve on other + * error. + */ +static int get_desc(struct blk_driver *drv, int devnum, struct blk_desc **descp) +{ + if (drv->desc) { + if (devnum < 0 || devnum >= drv->max_devs) + return -ENODEV; + *descp = &drv->desc[devnum]; + return 0; + } + if (!drv->get_dev) + return -ENOSYS; + + return drv->get_dev(devnum, descp); +} + +#ifdef HAVE_BLOCK_DEVICE +int blk_list_part(enum if_type if_type) +{ + struct blk_driver *drv; + struct blk_desc *desc; + int devnum, ok; + bool first = true; + + drv = blk_driver_lookup_type(if_type); + if (!drv) + return -ENOSYS; + for (ok = 0, devnum = 0; devnum < drv->max_devs; ++devnum) { + if (get_desc(drv, devnum, &desc)) + continue; + if (desc->part_type != PART_TYPE_UNKNOWN) { + ++ok; + if (!first) + putc('\n'); + part_print(desc); + first = false; + } + } + if (!ok) + return -ENODEV; + + return 0; +} + +int blk_print_part_devnum(enum if_type if_type, int devnum) +{ + struct blk_driver *drv = blk_driver_lookup_type(if_type); + struct blk_desc *desc; + int ret; + + if (!drv) + return -ENOSYS; + ret = get_desc(drv, devnum, &desc); + if (ret) + return ret; + if (desc->type == DEV_TYPE_UNKNOWN) + return -ENOENT; + part_print(desc); + + return 0; +} + +void blk_list_devices(enum if_type if_type) +{ + struct blk_driver *drv = blk_driver_lookup_type(if_type); + struct blk_desc *desc; + int i; + + if (!drv) + return; + for (i = 0; i < drv->max_devs; ++i) { + if (get_desc(drv, i, &desc)) + continue; + if (desc->type == DEV_TYPE_UNKNOWN) + continue; /* list only known devices */ + printf("Device %d: ", i); + dev_print(desc); + } +} + +int blk_print_device_num(enum if_type if_type, int devnum) +{ + struct blk_driver *drv = blk_driver_lookup_type(if_type); + struct blk_desc *desc; + int ret; + + if (!drv) + return -ENOSYS; + ret = get_desc(drv, devnum, &desc); + if (ret) + return ret; + printf("\n%s device %d: ", drv->if_typename, devnum); + dev_print(desc); + + return 0; +} + +int blk_show_device(enum if_type if_type, int devnum) +{ + struct blk_driver *drv = blk_driver_lookup_type(if_type); + struct blk_desc *desc; + int ret; + + if (!drv) + return -ENOSYS; + printf("\nDevice %d: ", devnum); + if (devnum >= drv->max_devs) { + puts("unknown device\n"); + return -ENODEV; + } + ret = get_desc(drv, devnum, &desc); + if (ret) + return ret; + dev_print(desc); + + if (desc->type == DEV_TYPE_UNKNOWN) + return -ENOENT; + + return 0; +} +#endif /* HAVE_BLOCK_DEVICE */ + +struct blk_desc *blk_get_devnum_by_type(enum if_type if_type, int devnum) +{ + struct blk_driver *drv = blk_driver_lookup_type(if_type); + struct blk_desc *desc; + + if (!drv) + return NULL; + + if (get_desc(drv, devnum, &desc)) + return NULL; + + return desc; +} + +int blk_dselect_hwpart(struct blk_desc *desc, int hwpart) +{ + struct blk_driver *drv = blk_driver_lookup_type(desc->if_type); + + if (!drv) + return -ENOSYS; + if (drv->select_hwpart) + return drv->select_hwpart(desc, hwpart); + + return 0; +} + +struct blk_desc *blk_get_devnum_by_typename(const char *if_typename, int devnum) +{ + struct blk_driver *drv = blk_driver_lookup_typename(if_typename); + struct blk_desc *desc; + + if (!drv) + return NULL; + + if (get_desc(drv, devnum, &desc)) + return NULL; + + return desc; +} + +ulong blk_read_devnum(enum if_type if_type, int devnum, lbaint_t start, + lbaint_t blkcnt, void *buffer) +{ + struct blk_driver *drv = blk_driver_lookup_type(if_type); + struct blk_desc *desc; + ulong n; + int ret; + + if (!drv) + return -ENOSYS; + ret = get_desc(drv, devnum, &desc); + if (ret) + return ret; + n = desc->block_read(desc, start, blkcnt, buffer); + if (IS_ERR_VALUE(n)) + return n; + + /* flush cache after read */ + flush_cache((ulong)buffer, blkcnt * desc->blksz); + + return n; +} + +ulong blk_write_devnum(enum if_type if_type, int devnum, lbaint_t start, + lbaint_t blkcnt, const void *buffer) +{ + struct blk_driver *drv = blk_driver_lookup_type(if_type); + struct blk_desc *desc; + int ret; + + if (!drv) + return -ENOSYS; + ret = get_desc(drv, devnum, &desc); + if (ret) + return ret; + return desc->block_write(desc, start, blkcnt, buffer); +} + +int blk_select_hwpart_devnum(enum if_type if_type, int devnum, int hwpart) +{ + struct blk_driver *drv = blk_driver_lookup_type(if_type); + struct blk_desc *desc; + int ret; + + if (!drv) + return -ENOSYS; + ret = get_desc(drv, devnum, &desc); + if (ret) + return ret; + return drv->select_hwpart(desc, hwpart); +} -- cgit v1.1