/* SPDX-License-Identifier: LGPL-2.1-or-later */ #pragma once #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 { 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; char *node; sd_device *dev; char *backing_file; bool relinquished; 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 */ }; /* 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 loop_flags, int lock_op, LoopDevice **ret); int loop_device_make_by_path(const char *path, int open_flags, uint32_t loop_flags, int lock_op, LoopDevice **ret); int loop_device_open_full(const char *loop_path, int loop_fd, int open_flags, int lock_op, LoopDevice **ret); static inline int loop_device_open(const char *loop_path, int open_flags, int lock_op, LoopDevice **ret) { return loop_device_open_full(loop_path, -1, open_flags, lock_op, ret); } 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);