/* SPDX-License-Identifier: GPL-2.0-only */ /* * reservations.h * * Allocation reservations function prototypes and structures. * * Copyright (C) 2010 Novell. All rights reserved. */ #ifndef OCFS2_RESERVATIONS_H #define OCFS2_RESERVATIONS_H #include <linux/rbtree.h> #define OCFS2_DEFAULT_RESV_LEVEL … #define OCFS2_MAX_RESV_LEVEL … #define OCFS2_MIN_RESV_LEVEL … struct ocfs2_alloc_reservation { … }; #define OCFS2_RESV_FLAG_INUSE … #define OCFS2_RESV_FLAG_TMP … #define OCFS2_RESV_FLAG_DIR … struct ocfs2_reservation_map { … }; void ocfs2_resv_init_once(struct ocfs2_alloc_reservation *resv); #define OCFS2_RESV_TYPES … void ocfs2_resv_set_type(struct ocfs2_alloc_reservation *resv, unsigned int flags); int ocfs2_dir_resv_allowed(struct ocfs2_super *osb); /** * ocfs2_resv_discard() - truncate a reservation * @resmap: * @resv: the reservation to truncate. * * After this function is called, the reservation will be empty, and * unlinked from the rbtree. */ void ocfs2_resv_discard(struct ocfs2_reservation_map *resmap, struct ocfs2_alloc_reservation *resv); /** * ocfs2_resmap_init() - Initialize fields of a reservations bitmap * @osb: struct ocfs2_super to be saved in resmap * @resmap: struct ocfs2_reservation_map to initialize */ void ocfs2_resmap_init(struct ocfs2_super *osb, struct ocfs2_reservation_map *resmap); /** * ocfs2_resmap_restart() - "restart" a reservation bitmap * @resmap: reservations bitmap * @clen: Number of valid bits in the bitmap * @disk_bitmap: the disk bitmap this resmap should refer to. * * Re-initialize the parameters of a reservation bitmap. This is * useful for local alloc window slides. * * This function will call ocfs2_trunc_resv against all existing * reservations. A future version will recalculate existing * reservations based on the new bitmap. */ void ocfs2_resmap_restart(struct ocfs2_reservation_map *resmap, unsigned int clen, char *disk_bitmap); /** * ocfs2_resmap_uninit() - uninitialize a reservation bitmap structure * @resmap: the struct ocfs2_reservation_map to uninitialize */ void ocfs2_resmap_uninit(struct ocfs2_reservation_map *resmap); /** * ocfs2_resmap_resv_bits() - Return still-valid reservation bits * @resmap: reservations bitmap * @resv: reservation to base search from * @cstart: start of proposed allocation * @clen: length (in clusters) of proposed allocation * * Using the reservation data from resv, this function will compare * resmap and resmap->m_disk_bitmap to determine what part (if any) of * the reservation window is still clear to use. If resv is empty, * this function will try to allocate a window for it. * * On success, zero is returned and the valid allocation area is set in cstart * and clen. * * Returns -ENOSPC if reservations are disabled. */ int ocfs2_resmap_resv_bits(struct ocfs2_reservation_map *resmap, struct ocfs2_alloc_reservation *resv, int *cstart, int *clen); /** * ocfs2_resmap_claimed_bits() - Tell the reservation code that bits were used. * @resmap: reservations bitmap * @resv: optional reservation to recalulate based on new bitmap * @cstart: start of allocation in clusters * @clen: end of allocation in clusters. * * Tell the reservation code that bits were used to fulfill allocation in * resmap. The bits don't have to have been part of any existing * reservation. But we must always call this function when bits are claimed. * Internally, the reservations code will use this information to mark the * reservations bitmap. If resv is passed, it's next allocation window will be * calculated. It also expects that 'cstart' is the same as we passed back * from ocfs2_resmap_resv_bits(). */ void ocfs2_resmap_claimed_bits(struct ocfs2_reservation_map *resmap, struct ocfs2_alloc_reservation *resv, u32 cstart, u32 clen); #endif /* OCFS2_RESERVATIONS_H */
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