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Diffstat (limited to 'kernel/xloop_file_fmt.h')
| -rw-r--r-- | kernel/xloop_file_fmt.h | 388 |
1 files changed, 0 insertions, 388 deletions
diff --git a/kernel/xloop_file_fmt.h b/kernel/xloop_file_fmt.h deleted file mode 100644 index 20589c1..0000000 --- a/kernel/xloop_file_fmt.h +++ /dev/null @@ -1,388 +0,0 @@ -/* SPDX-License-Identifier: GPL-2.0 */ -/* - * xloop_file_fmt.h - * - * File format subsystem for the xloop device module. - * - * Copyright (C) 2019 Manuel Bentele <development@manuel-bentele.de> - */ - -#ifndef _LINUX_XLOOP_FILE_FMT_H -#define _LINUX_XLOOP_FILE_FMT_H - -#include "xloop_main.h" - -struct xloop_file_fmt; - -#define XLO_FILE_FMT_RAW 0 -#define XLO_FILE_FMT_QCOW 1 -#define XLO_FILE_FMT_VDI 2 -#define XLO_FILE_FMT_VMDK 3 -#define MAX_XLO_FILE_FMT (XLO_FILE_FMT_VMDK + 1) - -/** - * struct xloop_file_fmt_ops - File format subsystem operations - * - * Data structure representing the file format subsystem interface. - */ -struct xloop_file_fmt_ops { - /** - * @init: Initialization callback function - */ - int (*init) (struct xloop_file_fmt *xlo_fmt); - - /** - * @exit: Release callback function - */ - void (*exit) (struct xloop_file_fmt *xlo_fmt); - - /** - * @read: Read IO callback function - */ - int (*read) (struct xloop_file_fmt *xlo_fmt, - struct request *rq); - - /** - * @write: Write IO callback function - */ - int (*write) (struct xloop_file_fmt *xlo_fmt, - struct request *rq); - - /** - * @read_aio: Asynchronous read IO callback function - */ - int (*read_aio) (struct xloop_file_fmt *xlo_fmt, - struct request *rq); - - /** - * @write_aio: Asynchronous write IO callback function - */ - int (*write_aio) (struct xloop_file_fmt *xlo_fmt, - struct request *rq); - - /** - * @zero: Zero (discard) IO callback function - */ - int (*write_zeros) (struct xloop_file_fmt *xlo_fmt, - struct request *rq); - - /** - * @discard: Discard IO callback function - */ - int (*discard) (struct xloop_file_fmt *xlo_fmt, - struct request *rq); - - /** - * @flush: Flush callback function - */ - int (*flush) (struct xloop_file_fmt *xlo_fmt); - - /** - * @sector_size: Get sector size callback function - */ - loff_t (*sector_size) (struct xloop_file_fmt *xlo_fmt, - struct file *file, loff_t offset, loff_t sizelimit); -}; - -/** - * struct xloop_file_fmt_driver - File format subsystem driver - * - * Data structure to implement file format drivers for the file format - * subsystem. - */ -struct xloop_file_fmt_driver { - /** - * @name: Name of the file format driver - */ - const char *name; - - /** - * @file_fmt_type: xloop file format type of the file format driver - */ - const u32 file_fmt_type; - - /** - * @ops: Driver's implemented file format operations - */ - struct xloop_file_fmt_ops *ops; - - /** - * @ops: Owner of the file format driver - */ - struct module *owner; -}; - -/* - * states of the file format - * - * transitions: - * xloop_file_fmt_init(...) - * ---> uninitialized ------------------------------> initialized - * xloop_file_fmt_exit(...) - * initialized ------------------------------> uninitialized - * xloop_file_fmt_read(...) - * initialized ------------------------------> initialized - * xloop_file_fmt_read_aio(...) - * initialized ------------------------------> initialized - * xloop_file_fmt_write(...) - * initialized ------------------------------> initialized - * xloop_file_fmt_write_aio(...) - * initialized ------------------------------> initialized - * xloop_file_fmt_discard(...) - * initialized ------------------------------> initialized - * xloop_file_fmt_flush(...) - * initialized ------------------------------> initialized - * xloop_file_fmt_sector_size(...) - * initialized ------------------------------> initialized - * - * xloop_file_fmt_change(...) - * +-----------------------------------------------------------+ - * | exit(...) init(...) | - * | initialized -------> uninitialized -------> initialized | - * +-----------------------------------------------------------+ - */ -enum { - file_fmt_uninitialized = 0, - file_fmt_initialized -}; - -/** - * struct xloop_file_fmt - xloop file format - * - * Data structure to use with the file format the xloop file format subsystem. - */ -struct xloop_file_fmt { - /** - * @file_fmt_type: Current type of the xloop file format - */ - u32 file_fmt_type; - - /** - * @file_fmt_state: Current state of the xloop file format - */ - int file_fmt_state; - - /** - * @xlo: Link to a file format's xloop device - */ - struct xloop_device *xlo; - - /** - * @private_data: Optional link to a file format's driver specific data - */ - void *private_data; -}; - - -/* subsystem functions for the driver implementation */ - -/** - * xloop_file_fmt_register_driver - Register a xloop file format driver - * @drv: File format driver - * - * Registers the specified xloop file format driver @drv by the xloop file format - * subsystem. - */ -extern int xloop_file_fmt_register_driver(struct xloop_file_fmt_driver *drv); - -/** - * xloop_file_fmt_unregister_driver - Unregister a xloop file format driver - * @drv: File format driver - * - * Unregisters the specified xloop file format driver @drv from the xloop file - * format subsystem. - */ -extern void xloop_file_fmt_unregister_driver(struct xloop_file_fmt_driver *drv); - - -/* subsystem functions for subsystem usage */ - -/** - * xloop_file_fmt_alloc - Allocate a xloop file format - * - * Dynamically allocates a xloop file format and returns a pointer to the - * created xloop file format. - */ -extern struct xloop_file_fmt *xloop_file_fmt_alloc(void); - -/** - * xloop_file_fmt_free - Free an allocated xloop file format - * @xlo_fmt: xloop file format - * - * Frees the already allocated xloop file format @xlo_fmt. - */ -extern void xloop_file_fmt_free(struct xloop_file_fmt *xlo_fmt); - -/** - * xloop_file_fmt_set_xlo - Set the xloop file format's xloop device - * @xlo_fmt: xloop file format - * @xlo: xloop device - * - * The link to the xloop device @xlo is set in the xloop file format @xlo_fmt. - */ -extern int xloop_file_fmt_set_xlo(struct xloop_file_fmt *xlo_fmt, - struct xloop_device *xlo); - -/** - * xloop_file_fmt_get_xlo - Get the xloop file format's xloop device - * @xlo_fmt: xloop file format - * - * Returns a pointer to the xloop device of the xloop file format @xlo_fmt. - */ -extern struct xloop_device *xloop_file_fmt_get_xlo(struct xloop_file_fmt *xlo_fmt); - -/** - * xloop_file_fmt_to_dev - Get the xloop file format's disk device - * @xlo_fmt: xloop file format - * - * Returns a pointer to the disk device of the xloop file format's xloop device. - */ -extern inline struct device *xloop_file_fmt_to_dev(struct xloop_file_fmt *xlo_fmt); - -/** - * xloop_file_fmt_init - Initialize a xloop file format - * @xlo_fmt: xloop file format - * @file_fmt_type: Type of the file format - * - * Initializes the specified xloop file format @xlo_fmt and sets up the correct - * file format type @file_fmt_type. Depending on @file_fmt_type, the correct - * xloop file format driver is loaded in the subsystems backend. If no xloop file - * format driver for the specified file format is available an error is - * returned. - */ -extern int xloop_file_fmt_init(struct xloop_file_fmt *xlo_fmt, - u32 file_fmt_type); - -/** - * xloop_file_fmt_exit - Release a xloop file format - * @xlo_fmt: xloop file format - * - * Releases the specified xloop file format @xlo_fmt and all its resources. - */ -extern void xloop_file_fmt_exit(struct xloop_file_fmt *xlo_fmt); - -/** - * xloop_file_fmt_read - Read IO from a xloop file format - * @xlo_fmt: xloop file format - * @rq: IO Request - * - * Reads IO from the file format's xloop device by sending the IO read request - * @rq to the xloop file format subsystem. The subsystem calls the registered - * callback function of the suitable xloop file format driver. - */ -extern int xloop_file_fmt_read(struct xloop_file_fmt *xlo_fmt, - struct request *rq); - -/** - * xloop_file_fmt_read_aio - Read IO from a xloop file format asynchronously - * @xlo_fmt: xloop file format - * @rq: IO Request - * - * Reads IO from the file format's xloop device asynchronously by sending the - * IO read aio request @rq to the xloop file format subsystem. The subsystem - * calls the registered callback function of the suitable xloop file format - * driver. - */ -extern int xloop_file_fmt_read_aio(struct xloop_file_fmt *xlo_fmt, - struct request *rq); - -/** - * xloop_file_fmt_write - Write IO to a xloop file format - * @xlo_fmt: xloop file format - * @rq: IO Request - * - * Write IO to the file format's xloop device by sending the IO write request - * @rq to the xloop file format subsystem. The subsystem calls the registered - * callback function of the suitable xloop file format driver. - */ -extern int xloop_file_fmt_write(struct xloop_file_fmt *xlo_fmt, - struct request *rq); - -/** - * xloop_file_fmt_write_aio - Write IO to a xloop file format asynchronously - * @xlo_fmt: xloop file format - * @rq: IO Request - * - * Write IO to the file format's xloop device asynchronously by sending the - * IO write aio request @rq to the xloop file format subsystem. The subsystem - * calls the registered callback function of the suitable xloop file format - * driver. - */ -extern int xloop_file_fmt_write_aio(struct xloop_file_fmt *xlo_fmt, - struct request *rq); - -/** - * xloop_file_fmt_write_zeros - Zero (discard) IO on a xloop file format - * @xlo_fmt: xloop file format - * @rq: IO Request - * - * Zero (discard) IO on the file format's xloop device by sending the IO write - * zeros request @rq to the xloop file format subsystem. The subsystem calls the - * registered callback function of the suitable xloop file format driver. - */ -extern int xloop_file_fmt_write_zeros(struct xloop_file_fmt *xlo_fmt, - struct request *rq); - -/** - * xloop_file_fmt_discard - Discard IO on a xloop file format - * @xlo_fmt: xloop file format - * @rq: IO Request - * - * Discard IO on the file format's xloop device by sending the IO discard - * request @rq to the xloop file format subsystem. The subsystem calls the - * registered callback function of the suitable xloop file format driver. - */ -extern int xloop_file_fmt_discard(struct xloop_file_fmt *xlo_fmt, - struct request *rq); - -/** - * xloop_file_fmt_flush - Flush a xloop file format - * @xlo_fmt: xloop file format - * - * Flush the file format's xloop device by calling the registered callback - * function of the suitable xloop file format driver. - */ -extern int xloop_file_fmt_flush(struct xloop_file_fmt *xlo_fmt); - -/** - * xloop_file_fmt_sector_size - Get sector size of a xloop file format - * @xlo_fmt: xloop file format - * @file: xloop file formats file for sector size calculation - * @offset: Offset within the file for sector size calculation - * @sizelimit: Sizelimit of the file for sector size calculation - * - * Returns the physical sector size of the given xloop file format's file. - * If the xloop file format implements a sparse disk image format, then this - * function returns the virtual sector size. - */ -extern loff_t xloop_file_fmt_sector_size(struct xloop_file_fmt *xlo_fmt, - struct file *file, loff_t offset, loff_t sizelimit); - -/** - * xloop_file_fmt_change - Change the xloop file format's type - * @xlo_fmt: xloop file format - * @file_fmt_type_new: xloop file format type - * - * Changes the file format type of the already initialized xloop file format - * @xlo_fmt. Therefore, the function releases the old file format and frees all - * of its resources before the xloop file format @xlo_fmt is initialized and set - * up with the new file format @file_fmt_type_new. - */ -extern int xloop_file_fmt_change(struct xloop_file_fmt *xlo_fmt, - u32 file_fmt_type_new); - - -/* helper functions of the subsystem */ - -/** - * xloop_file_fmt_print_type - Convert file format type to string - * @file_fmt_type: xloop file format type - * @file_fmt_name: xloop file format type string - * - * Converts the specified numeric @file_fmt_type value into a human readable - * string stating the file format as string in @file_fmt_name. - */ -extern ssize_t xloop_file_fmt_print_type(u32 file_fmt_type, - char *file_fmt_name); - -#endif |