diff options
Diffstat (limited to 'loop_file_fmt.h')
| -rw-r--r-- | loop_file_fmt.h | 281 |
1 files changed, 152 insertions, 129 deletions
diff --git a/loop_file_fmt.h b/loop_file_fmt.h index 8a16c86..38d6a3b 100644 --- a/loop_file_fmt.h +++ b/loop_file_fmt.h @@ -2,102 +2,109 @@ /* * loop_file_fmt.h * - * File format subsystem for the loop device module. + * File format subsystem for the xloop device module. * * Copyright (C) 2019 Manuel Bentele <development@manuel-bentele.de> */ -#ifndef _LINUX_LOOP_FILE_FMT_H -#define _LINUX_LOOP_FILE_FMT_H +#ifndef _LINUX_XLOOP_FILE_FMT_H +#define _LINUX_XLOOP_FILE_FMT_H #include "loop_main.h" -struct loop_file_fmt; +struct xloop_file_fmt; -#define LO_FILE_FMT_RAW 0 -#define LO_FILE_FMT_QCOW 1 -#define LO_FILE_FMT_VDI 2 -#define LO_FILE_FMT_VMDK 3 -#define MAX_LO_FILE_FMT (LO_FILE_FMT_VMDK + 1) +#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 loop_file_fmt_ops - File format subsystem operations + * struct xloop_file_fmt_ops - File format subsystem operations * * Data structure representing the file format subsystem interface. */ -struct loop_file_fmt_ops { +struct xloop_file_fmt_ops { /** * @init: Initialization callback function */ - int (*init) (struct loop_file_fmt *lo_fmt); + int (*init) (struct xloop_file_fmt *xlo_fmt); /** * @exit: Release callback function */ - void (*exit) (struct loop_file_fmt *lo_fmt); + void (*exit) (struct xloop_file_fmt *xlo_fmt); /** * @read: Read IO callback function */ - int (*read) (struct loop_file_fmt *lo_fmt, - struct request *rq); + int (*read) (struct xloop_file_fmt *xlo_fmt, + struct request *rq); /** * @write: Write IO callback function */ - int (*write) (struct loop_file_fmt *lo_fmt, - struct request *rq); + int (*write) (struct xloop_file_fmt *xlo_fmt, + struct request *rq); /** * @read_aio: Asynchronous read IO callback function */ - int (*read_aio) (struct loop_file_fmt *lo_fmt, - struct request *rq); + int (*read_aio) (struct xloop_file_fmt *xlo_fmt, + struct request *rq); /** * @write_aio: Asynchronous write IO callback function */ - int (*write_aio) (struct loop_file_fmt *lo_fmt, - struct request *rq); + 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 loop_file_fmt *lo_fmt, + int (*discard) (struct xloop_file_fmt *xlo_fmt, struct request *rq); /** * @flush: Flush callback function */ - int (*flush) (struct loop_file_fmt *lo_fmt); + int (*flush) (struct xloop_file_fmt *xlo_fmt); /** * @sector_size: Get sector size callback function */ - loff_t (*sector_size) (struct loop_file_fmt *lo_fmt); + loff_t (*sector_size) (struct xloop_file_fmt *xlo_fmt, + struct file *file, loff_t offset, loff_t sizelimit); }; /** - * struct loop_file_fmt_driver - File format subsystem driver + * struct xloop_file_fmt_driver - File format subsystem driver * * Data structure to implement file format drivers for the file format * subsystem. */ -struct loop_file_fmt_driver { +struct xloop_file_fmt_driver { /** * @name: Name of the file format driver */ const char *name; /** - * @file_fmt_type: Loop file format type of the file format driver + * @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 loop_file_fmt_ops *ops; + struct xloop_file_fmt_ops *ops; /** * @ops: Owner of the file format driver @@ -109,26 +116,26 @@ struct loop_file_fmt_driver { * states of the file format * * transitions: - * loop_file_fmt_init(...) + * xloop_file_fmt_init(...) * ---> uninitialized ------------------------------> initialized - * loop_file_fmt_exit(...) + * xloop_file_fmt_exit(...) * initialized ------------------------------> uninitialized - * loop_file_fmt_read(...) + * xloop_file_fmt_read(...) * initialized ------------------------------> initialized - * loop_file_fmt_read_aio(...) + * xloop_file_fmt_read_aio(...) * initialized ------------------------------> initialized - * loop_file_fmt_write(...) + * xloop_file_fmt_write(...) * initialized ------------------------------> initialized - * loop_file_fmt_write_aio(...) + * xloop_file_fmt_write_aio(...) * initialized ------------------------------> initialized - * loop_file_fmt_discard(...) + * xloop_file_fmt_discard(...) * initialized ------------------------------> initialized - * loop_file_fmt_flush(...) + * xloop_file_fmt_flush(...) * initialized ------------------------------> initialized - * loop_file_fmt_sector_size(...) + * xloop_file_fmt_sector_size(...) * initialized ------------------------------> initialized * - * loop_file_fmt_change(...) + * xloop_file_fmt_change(...) * +-----------------------------------------------------------+ * | exit(...) init(...) | * | initialized -------> uninitialized -------> initialized | @@ -140,25 +147,25 @@ enum { }; /** - * struct loop_file_fmt - Loop file format + * struct xloop_file_fmt - xloop file format * - * Data structure to use with the file format the loop file format subsystem. + * Data structure to use with the file format the xloop file format subsystem. */ -struct loop_file_fmt { +struct xloop_file_fmt { /** - * @file_fmt_type: Current type of the loop file format + * @file_fmt_type: Current type of the xloop file format */ u32 file_fmt_type; /** - * @file_fmt_state: Current state of the loop file format + * @file_fmt_state: Current state of the xloop file format */ int file_fmt_state; /** - * @lo: Link to a file format's loop device + * @xlo: Link to a file format's xloop device */ - struct loop_device *lo; + struct xloop_device *xlo; /** * @private_data: Optional link to a file format's driver specific data @@ -170,188 +177,204 @@ struct loop_file_fmt { /* subsystem functions for the driver implementation */ /** - * loop_file_fmt_register_driver - Register a loop file format driver + * xloop_file_fmt_register_driver - Register a xloop file format driver * @drv: File format driver * - * Registers the specified loop file format driver @drv by the loop file format + * Registers the specified xloop file format driver @drv by the xloop file format * subsystem. */ -extern int loop_file_fmt_register_driver(struct loop_file_fmt_driver *drv); +extern int xloop_file_fmt_register_driver(struct xloop_file_fmt_driver *drv); /** - * loop_file_fmt_unregister_driver - Unregister a loop file format driver + * xloop_file_fmt_unregister_driver - Unregister a xloop file format driver * @drv: File format driver * - * Unregisters the specified loop file format driver @drv from the loop file + * Unregisters the specified xloop file format driver @drv from the xloop file * format subsystem. */ -extern void loop_file_fmt_unregister_driver(struct loop_file_fmt_driver *drv); +extern void xloop_file_fmt_unregister_driver(struct xloop_file_fmt_driver *drv); /* subsystem functions for subsystem usage */ /** - * loop_file_fmt_alloc - Allocate a loop file format + * xloop_file_fmt_alloc - Allocate a xloop file format * - * Dynamically allocates a loop file format and returns a pointer to the - * created loop file format. + * Dynamically allocates a xloop file format and returns a pointer to the + * created xloop file format. */ -extern struct loop_file_fmt *loop_file_fmt_alloc(void); +extern struct xloop_file_fmt *xloop_file_fmt_alloc(void); /** - * loop_file_fmt_free - Free an allocated loop file format - * @lo_fmt: Loop file format + * xloop_file_fmt_free - Free an allocated xloop file format + * @xlo_fmt: xloop file format * - * Frees the already allocated loop file format @lo_fmt. + * Frees the already allocated xloop file format @xlo_fmt. */ -extern void loop_file_fmt_free(struct loop_file_fmt *lo_fmt); +extern void xloop_file_fmt_free(struct xloop_file_fmt *xlo_fmt); /** - * loop_file_fmt_set_lo - Set the loop file format's loop device - * @lo_fmt: Loop file format - * @lo: Loop device + * 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 loop device @lo is set in the loop file format @lo_fmt. + * The link to the xloop device @xlo is set in the xloop file format @xlo_fmt. */ -extern int loop_file_fmt_set_lo(struct loop_file_fmt *lo_fmt, - struct loop_device *lo); +extern int xloop_file_fmt_set_xlo(struct xloop_file_fmt *xlo_fmt, + struct xloop_device *xlo); /** - * loop_file_fmt_get_lo - Get the loop file format's loop device - * @lo_fmt: Loop file format + * xloop_file_fmt_get_xlo - Get the xloop file format's xloop device + * @xlo_fmt: xloop file format * - * Returns a pointer to the loop device of the loop file format @lo_fmt. + * Returns a pointer to the xloop device of the xloop file format @xlo_fmt. */ -extern struct loop_device *loop_file_fmt_get_lo(struct loop_file_fmt *lo_fmt); +extern struct xloop_device *xloop_file_fmt_get_xlo(struct xloop_file_fmt *xlo_fmt); /** - * loop_file_fmt_init - Initialize a loop file format - * @lo_fmt: Loop file format + * 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 loop file format @lo_fmt and sets up the correct + * 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 - * loop file format driver is loaded in the subsystems backend. If no loop file + * 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 loop_file_fmt_init(struct loop_file_fmt *lo_fmt, +extern int xloop_file_fmt_init(struct xloop_file_fmt *xlo_fmt, u32 file_fmt_type); /** - * loop_file_fmt_exit - Release a loop file format - * @lo_fmt: Loop file format + * xloop_file_fmt_exit - Release a xloop file format + * @xlo_fmt: xloop file format * - * Releases the specified loop file format @lo_fmt and all its resources. + * Releases the specified xloop file format @xlo_fmt and all its resources. */ -extern void loop_file_fmt_exit(struct loop_file_fmt *lo_fmt); +extern void xloop_file_fmt_exit(struct xloop_file_fmt *xlo_fmt); /** - * loop_file_fmt_read - Read IO from a loop file format - * @lo_fmt: Loop file format + * 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 loop device by sending the IO read request - * @rq to the loop file format subsystem. The subsystem calls the registered - * callback function of the suitable loop file format driver. + * 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 loop_file_fmt_read(struct loop_file_fmt *lo_fmt, +extern int xloop_file_fmt_read(struct xloop_file_fmt *xlo_fmt, struct request *rq); /** - * loop_file_fmt_read_aio - Read IO from a loop file format asynchronously - * @lo_fmt: Loop file format + * 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 loop device asynchronously by sending the - * IO read aio request @rq to the loop file format subsystem. The subsystem - * calls the registered callback function of the suitable loop file format + * 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 loop_file_fmt_read_aio(struct loop_file_fmt *lo_fmt, +extern int xloop_file_fmt_read_aio(struct xloop_file_fmt *xlo_fmt, struct request *rq); /** - * loop_file_fmt_write - Write IO to a loop file format - * @lo_fmt: Loop file format + * 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 loop device by sending the IO write request - * @rq to the loop file format subsystem. The subsystem calls the registered - * callback function of the suitable loop file format driver. + * 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 loop_file_fmt_write(struct loop_file_fmt *lo_fmt, +extern int xloop_file_fmt_write(struct xloop_file_fmt *xlo_fmt, struct request *rq); /** - * loop_file_fmt_write_aio - Write IO to a loop file format asynchronously - * @lo_fmt: Loop file format + * 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 loop device asynchronously by sending the - * IO write aio request @rq to the loop file format subsystem. The subsystem - * calls the registered callback function of the suitable loop file format + * 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 loop_file_fmt_write_aio(struct loop_file_fmt *lo_fmt, +extern int xloop_file_fmt_write_aio(struct xloop_file_fmt *xlo_fmt, struct request *rq); /** - * loop_file_fmt_discard - Discard IO on a loop file format - * @lo_fmt: Loop file format + * 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 loop device by sending the IO discard - * request @rq to the loop file format subsystem. The subsystem calls the - * registered callback function of the suitable loop file format driver. + * 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 loop_file_fmt_discard(struct loop_file_fmt *lo_fmt, +extern int xloop_file_fmt_discard(struct xloop_file_fmt *xlo_fmt, struct request *rq); /** - * loop_file_fmt_flush - Flush a loop file format - * @lo_fmt: Loop file format + * xloop_file_fmt_flush - Flush a xloop file format + * @xlo_fmt: xloop file format * - * Flush the file format's loop device by calling the registered callback - * function of the suitable loop file format driver. + * Flush the file format's xloop device by calling the registered callback + * function of the suitable xloop file format driver. */ -extern int loop_file_fmt_flush(struct loop_file_fmt *lo_fmt); +extern int xloop_file_fmt_flush(struct xloop_file_fmt *xlo_fmt); /** - * loop_file_fmt_sector_size - Get sector size of a loop file format - * @lo_fmt: Loop file format + * 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 loop file format's loop device. - * If the loop file format implements a sparse disk image format, then this + * 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 loop_file_fmt_sector_size(struct loop_file_fmt *lo_fmt); +extern loff_t xloop_file_fmt_sector_size(struct xloop_file_fmt *xlo_fmt, + struct file *file, loff_t offset, loff_t sizelimit); /** - * loop_file_fmt_change - Change the loop file format's type - * @lo_fmt: Loop file format - * @file_fmt_type_new: Loop file format type + * 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 loop file format - * @lo_fmt. Therefore, the function releases the old file format and frees all - * of its resources before the loop file format @lo_fmt is initialized and set + * 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 loop_file_fmt_change(struct loop_file_fmt *lo_fmt, +extern int xloop_file_fmt_change(struct xloop_file_fmt *xlo_fmt, u32 file_fmt_type_new); /* helper functions of the subsystem */ /** - * loop_file_fmt_print_type - Convert file format type to string - * @file_fmt_type: Loop file format type - * @file_fmt_name: Loop file format type string + * 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 loop_file_fmt_print_type(u32 file_fmt_type, +extern ssize_t xloop_file_fmt_print_type(u32 file_fmt_type, char *file_fmt_name); #endif |