reservations.c | Explore in Territory

// SPDX-License-Identifier: GPL-2.0-only
/*
 * reservations.c
 *
 * Allocation reservations implementation
 *
 * Some code borrowed from fs/ext3/balloc.c and is:
 *
 * Copyright (C) 1992, 1993, 1994, 1995
 * Remy Card ([email protected])
 * Laboratoire MASI - Institut Blaise Pascal
 * Universite Pierre et Marie Curie (Paris VI)
 *
 * The rest is copyright (C) 2010 Novell.  All rights reserved.
 */

#include <linux/fs.h>
#include <linux/types.h>
#include <linux/highmem.h>
#include <linux/bitops.h>
#include <linux/list.h>

#include <cluster/masklog.h>

#include "ocfs2.h"
#include "ocfs2_trace.h"

#ifdef CONFIG_OCFS2_DEBUG_FS
#define OCFS2_CHECK_RESERVATIONS
#endif

static DEFINE_SPINLOCK(resv_lock);

int ocfs2_dir_resv_allowed(struct ocfs2_super *osb)
{ … }

static unsigned int ocfs2_resv_window_bits(struct ocfs2_reservation_map *resmap,
					   struct ocfs2_alloc_reservation *resv)
{ … }

static inline unsigned int ocfs2_resv_end(struct ocfs2_alloc_reservation *resv)
{ … }

static inline int ocfs2_resv_empty(struct ocfs2_alloc_reservation *resv)
{ … }

static inline int ocfs2_resmap_disabled(struct ocfs2_reservation_map *resmap)
{ … }

static void ocfs2_dump_resv(struct ocfs2_reservation_map *resmap)
{ … }

#ifdef OCFS2_CHECK_RESERVATIONS
static int ocfs2_validate_resmap_bits(struct ocfs2_reservation_map *resmap,
				      int i,
				      struct ocfs2_alloc_reservation *resv)
{ … }

static void ocfs2_check_resmap(struct ocfs2_reservation_map *resmap)
{ … }
#else
static inline void ocfs2_check_resmap(struct ocfs2_reservation_map *resmap)
{

}
#endif

void ocfs2_resv_init_once(struct ocfs2_alloc_reservation *resv)
{ … }

void ocfs2_resv_set_type(struct ocfs2_alloc_reservation *resv,
			 unsigned int flags)
{ … }

void ocfs2_resmap_init(struct ocfs2_super *osb,
		      struct ocfs2_reservation_map *resmap)
{ … }

static void ocfs2_resv_mark_lru(struct ocfs2_reservation_map *resmap,
				struct ocfs2_alloc_reservation *resv)
{ … }

static void __ocfs2_resv_trunc(struct ocfs2_alloc_reservation *resv)
{ … }

static void ocfs2_resv_remove(struct ocfs2_reservation_map *resmap,
			      struct ocfs2_alloc_reservation *resv)
{ … }

static void __ocfs2_resv_discard(struct ocfs2_reservation_map *resmap,
				 struct ocfs2_alloc_reservation *resv)
{ … }

/* does nothing if 'resv' is null */
void ocfs2_resv_discard(struct ocfs2_reservation_map *resmap,
			struct ocfs2_alloc_reservation *resv)
{ … }

static void ocfs2_resmap_clear_all_resv(struct ocfs2_reservation_map *resmap)
{ … }

void ocfs2_resmap_restart(struct ocfs2_reservation_map *resmap,
			  unsigned int clen, char *disk_bitmap)
{ … }

void ocfs2_resmap_uninit(struct ocfs2_reservation_map *resmap)
{ … }

static void ocfs2_resv_insert(struct ocfs2_reservation_map *resmap,
			      struct ocfs2_alloc_reservation *new)
{ … }

/**
 * ocfs2_find_resv_lhs() - find the window which contains goal
 * @resmap: reservation map to search
 * @goal: which bit to search for
 *
 * If a window containing that goal is not found, we return the window
 * which comes before goal. Returns NULL on empty rbtree or no window
 * before goal.
 */
static struct ocfs2_alloc_reservation *
ocfs2_find_resv_lhs(struct ocfs2_reservation_map *resmap, unsigned int goal)
{ … }

/*
 * We are given a range within the bitmap, which corresponds to a gap
 * inside the reservations tree (search_start, search_len). The range
 * can be anything from the whole bitmap, to a gap between
 * reservations.
 *
 * The start value of *rstart is insignificant.
 *
 * This function searches the bitmap range starting at search_start
 * with length search_len for a set of contiguous free bits. We try
 * to find up to 'wanted' bits, but can sometimes return less.
 *
 * Returns the length of allocation, 0 if no free bits are found.
 *
 * *cstart and *clen will also be populated with the result.
 */
static int ocfs2_resmap_find_free_bits(struct ocfs2_reservation_map *resmap,
				       unsigned int wanted,
				       unsigned int search_start,
				       unsigned int search_len,
				       unsigned int *rstart,
				       unsigned int *rlen)
{ … }

static void __ocfs2_resv_find_window(struct ocfs2_reservation_map *resmap,
				     struct ocfs2_alloc_reservation *resv,
				     unsigned int goal, unsigned int wanted)
{ … }

static void ocfs2_cannibalize_resv(struct ocfs2_reservation_map *resmap,
				   struct ocfs2_alloc_reservation *resv,
				   unsigned int wanted)
{ … }

static void ocfs2_resv_find_window(struct ocfs2_reservation_map *resmap,
				   struct ocfs2_alloc_reservation *resv,
				   unsigned int wanted)
{ … }

int ocfs2_resmap_resv_bits(struct ocfs2_reservation_map *resmap,
			   struct ocfs2_alloc_reservation *resv,
			   int *cstart, int *clen)
{ … }

static void
	ocfs2_adjust_resv_from_alloc(struct ocfs2_reservation_map *resmap,
				     struct ocfs2_alloc_reservation *resv,
				     unsigned int start, unsigned int end)
{ … }

void ocfs2_resmap_claimed_bits(struct ocfs2_reservation_map *resmap,
			       struct ocfs2_alloc_reservation *resv,
			       u32 cstart, u32 clen)
{ … }
linux/fs/ocfs2/reservations.c
