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/* SPDX-License-Identifier: LGPL-2.1-or-later */
#pragma once
#include <fcntl.h>
#include "sd-device.h"
#include "macro.h"
#include "time-util.h"
typedef struct LoopDevice LoopDevice;
/* Some helpers for setting up loopback block devices */
struct LoopDevice {
unsigned n_ref;
int fd;
int lock_fd;
int nr; /* The loopback device index (i.e. 4 for /dev/loop4); if this object encapsulates a non-loopback block device, set to -1 */
dev_t devno; /* The loopback device's own dev_t */
char *node;
sd_device *dev;
char *backing_file;
bool relinquished;
dev_t backing_devno; /* The backing file's dev_t */
ino_t backing_inode; /* The backing file's ino_t */
uint64_t diskseq; /* Block device sequence number, monothonically incremented by the kernel on create/attach, or 0 if we don't know */
uint64_t uevent_seqnum_not_before; /* uevent sequm right before we attached the loopback device, or UINT64_MAX if we don't know */
usec_t timestamp_not_before; /* CLOCK_MONOTONIC timestamp taken immediately before attaching the loopback device, or USEC_INFINITY if we don't know */
uint32_t sector_size;
uint64_t device_size;
};
/* Returns true if LoopDevice object is not actually a loopback device but some other block device we just wrap */
#define LOOP_DEVICE_IS_FOREIGN(d) ((d)->nr < 0)
int loop_device_make(int fd, int open_flags, uint64_t offset, uint64_t size, uint32_t sector_size, uint32_t loop_flags, int lock_op, LoopDevice **ret);
int loop_device_make_by_path_at(int dir_fd, const char *path, int open_flags, uint32_t sector_size, uint32_t loop_flags, int lock_op, LoopDevice **ret);
static inline int loop_device_make_by_path(const char *path, int open_flags, uint32_t sector_size, uint32_t loop_flags, int lock_op, LoopDevice **ret) {
return loop_device_make_by_path_at(AT_FDCWD, path, open_flags, sector_size, loop_flags, lock_op, ret);
}
int loop_device_make_by_path_memory(const char *path, int open_flags, uint32_t sector_size, uint32_t loop_flags, int lock_op, LoopDevice **ret);
int loop_device_open(sd_device *dev, int open_flags, int lock_op, LoopDevice **ret);
int loop_device_open_from_fd(int fd, int open_flags, int lock_op, LoopDevice **ret);
int loop_device_open_from_path(const char *path, int open_flags, int lock_op, LoopDevice **ret);
LoopDevice* loop_device_ref(LoopDevice *d);
LoopDevice* loop_device_unref(LoopDevice *d);
DEFINE_TRIVIAL_CLEANUP_FUNC(LoopDevice*, loop_device_unref);
void loop_device_relinquish(LoopDevice *d);
void loop_device_unrelinquish(LoopDevice *d);
int loop_device_refresh_size(LoopDevice *d, uint64_t offset, uint64_t size);
int loop_device_flock(LoopDevice *d, int operation);
int loop_device_sync(LoopDevice *d);
int loop_device_set_autoclear(LoopDevice *d, bool autoclear);
int loop_device_set_filename(LoopDevice *d, const char *name);
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