2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * Copyright 2008 Sun Microsystems, Inc. All rights reserved.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * Use is subject to license terms.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * BSD 3 Clause License
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * Copyright (c) 2007, The Storage Networking Industry Association.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * Redistribution and use in source and binary forms, with or without
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * modification, are permitted provided that the following conditions
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * - Redistributions of source code must retain the above copyright
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * notice, this list of conditions and the following disclaimer.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * - Redistributions in binary form must reproduce the above copyright
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * notice, this list of conditions and the following disclaimer in
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * the documentation and/or other materials provided with the
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * distribution.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * - Neither the name of The Storage Networking Industry Association (SNIA)
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * nor the names of its contributors may be used to endorse or promote
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * products derived from this software without specific prior written
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * permission.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * POSSIBILITY OF SUCH DAMAGE.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * Hash table size.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * Maximum number of chunk that can be cached.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * Size of bitmap table.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * Bit_MAP Word SIZE. This should be equal to 'sizeof (int)'.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * Bit_MAP Bit Per Word.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * Chunk of bit map in each node.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar#define BMAP_CHUNK_BYTES (BMAP_CHUNK_WORDS * BMAP_WSIZE)
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar#define BMAP_CHUNK_BITS (BMAP_CHUNK_WORDS * BMAP_BPW)
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar#define BMAP_CHUNK_OFF(p) (BMAP_CHUNK_NO(p) * BMAP_CHUNK_BITS)
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * Bitmap flags.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar#define BMAP_BINIT_ONES 0x00000001 /* initial value of bits is 1 */
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar#define BMAP_INUSE 0x00000002 /* slot is in use */
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * Macros of bitmap flags.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar#define BMAP_SET_FLAGS(b, f) ((b)->bm_flags |= (f))
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar#define BMAP_UNSET_FLAGS(b, f) ((b)->bm_flags &= ~(f))
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar#define BMAP_IS_INIT_ONES(b) ((b)->bm_flags & BMAP_BINIT_ONES)
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar#define BMAP_IS_INUSE(b) ((b)->bm_flags & BMAP_INUSE)
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar#define HASH(p) (((p) / BMAP_CHUNK_BITS) % BMAP_HASH_SIZE)
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * Calculate the memory size in bytes needed for the specified length
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * of bitmap.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar#define MEM_LEN(l) (ROUNDUP((l), BMAP_BPW) * BMAP_WSIZE)
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * Chunk flags.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar#define BMAP_CSET_DIRTY(cp) (cp)->c_flags |= BMAP_CDIRTY
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar#define BMAP_CDIRTY 0x00000001 /* the chunk is dirty */
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * Macros on chunk flags.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar#define BMAP_CIS_DIRTY(cp) ((cp)->c_flags & BMAP_CDIRTY)
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * When loading a bitmap chunk, if it is new set the bitmap
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * can be set according to the initial value of bits.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * Otherwise, it should be loaded from the file.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * Each chunk holds the followin information:
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * - A flag showing the status of the chunk, like being ditry or not.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * - Its offset in bits from the beginning of the vector.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * - Its length in bits.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * - Its memory length in use in bytes.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * - The bitmap vector.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * In addition to the above information, each chunk can be on two lists:
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * one the hash list, the other LRU list. The hash list is a MRU list,
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * meaning the MRU entry is at the head of the list.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * All the chunks are in the LRU list. When a chunk is needed and there is
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * no more room for allocating chunks, the first entry of this list is
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * reclaimed.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar uint_t bm_cmax; /* maximum number of cached chunks */
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar uint_t bm_ccur; /* current number of cached chunks */
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar dbmap_list_t bm_hash[BMAP_HASH_SIZE]; /* MRU hash table */
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * Disk bitmap table. Upon allocating a dbitmap, one slot
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * of this table will be used.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * Each chunk holds the followin information:
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * - Its offset in bits from the beginning of the vector.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * - Its length in bits.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * - Its memory length in use in bytes.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * - The bitmap vector.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * In addition to the above information, each chunk can be on a list:
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * one the hash list. The hash list is a MRU list, meaning that the
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * MRU entry is at the head of the list.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar uint_t bm_cmax; /* maximum number of cached chunks */
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar uint_t bm_ccur; /* current number of cached chunks */
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar bmap_list_t bm_hash[BMAP_HASH_SIZE]; /* MRU hash table */
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * Statistics gathering structure.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * Disk bitmap table. Upon allocating a bitmap, one slot
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * of this table will be used.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * Global instance of statistics variable.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * Convert bitmap descriptor to bitmap pointer.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * Allocate a bitmap descriptor. Sets the INUSE flag of the slot.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar return (-1);
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * Free a bitmap descriptor. Clears the INUSE flag of the slot.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * Generic function to set bit in a chunk. This can set or unset the
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * specified bit.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdarstatic inline int
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdarbmp_set(bmap_chunk_t *cp, u_quad_t bn, uint_t *vp)
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * Generic function to get bit in a chunk.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdarstatic inline int
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar rv = (cp->c_bmp[bn >> BMAP_BPW_SHIFT] & bit) != 0;
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * bm_chuck_setup
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * Set up the properties of the new chunk and position it in the hash list.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdarbm_chunk_setup(bitmap_t *bmp, bmap_chunk_t *cp, u_quad_t bn)
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * bm_chunk_new
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * Create a new chunk and keep track of memory used.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar cp->c_bmp = ndmp_malloc(sizeof (uint_t) * BMAP_CHUNK_WORDS);
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * bm_chunk_alloc
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * Allocate a chunk and return it. If the cache for the chunks is not
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * fully used, a new chunk is created.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * Free all chunks on the hash list.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * bm_chunks_free
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * Release the memory allocated for the chunks.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * bm_chunk_repositions
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * Re-position the chunk in the MRU hash table.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdarbm_chunk_reposition(bitmap_t *bmp, bmap_list_t *hp, bmap_chunk_t *cp)
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * bm_chunk_find
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * Find and return the chunks which holds the specified bit. Allocate
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * the chunk if necessary and re-position it in the hash table lists.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar if (bn >= cp->c_off && bn < (cp->c_off + cp->c_clen)) {
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * bmp_setval
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * Set a range of bits in the bitmap specified by the vector.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar for (cl = cp->c_off + cp->c_clen; bn < cl && bn < max; bn++) {
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * bmp_getval
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * Get a range of bits in the bitmap specified by the vector.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar for (cl = cp->c_off + cp->c_clen; bn < cl && bn < max; bn++) {
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * Initialize the hash table lists head.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * Allocate a bit map and return a handle to it.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * The hash table list are empty at this point. They are allocated
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * on demand.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar return (-1);
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * Free memory allocated for the bitmap.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * Get bits specified by the array of vectors.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * Set bits specified by the array of vectors.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * Convert bitmap descriptor to bitmap pointer.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * Convert bitmap pointer to bitmap descriptor.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * dbmd_alloc
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * Allocate a bitmap descriptor.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * Sets the INUSE flag of the slot.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar return (-1);
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * Free a bitmap descriptor.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * Clears the INUSE flag of the slot.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * Generic function to set bit in a chunk. This can
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * set or unset the specified bit.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdarstatic inline int
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdardbmp_set(dbmap_chunk_t *cp, u_quad_t bn, uint_t *vp)
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * dbmp_getlen
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * Get length of the bitmap.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * Generic function to get bit in a chunk.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdarstatic inline int
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar rv = (cp->c_bmp[bn >> BMAP_BPW_SHIFT] & bit) != 0;
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * dbm_chunk_seek
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * Seek in the file where the chunk is saved or should be saved.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar rv = (lseek(bmp->bm_fd, off, SEEK_SET) != off) ? -1 : 0;
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * dbm_chunk_flush
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * Save a chunk to file.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdardbm_chunk_flush(dbitmap_t *bmp, dbmap_chunk_t *cp)
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar else if (write(bmp->bm_fd, cp->c_bmp, cp->c_mlen) != cp->c_mlen)
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * dbm_chunk_load
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * Load a chunk from a file. If the chunk is a new one,
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * instead of reading from the disk, the memory for the
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * chunk is set to either all zeros or to all ones.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * Otherwise, if the chunk is not a new one, it's read
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * from the disk.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * The new chunk is positioned in the LRU and hash table
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * after its data is ready.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdardbm_chunk_load(dbitmap_t *bmp, dbmap_chunk_t *cp, u_quad_t bn, int new)
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar } else { /* BMAP_OLD_CHUNK */
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * dbm_chunk_new
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * Create a new chunk and keep track of memory used.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar cp->c_bmp = ndmp_malloc(sizeof (uint_t) * BMAP_CHUNK_WORDS);
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar } else if (!dbm_chunk_load(bmp, cp, bn, BMAP_NEW_CHUNK)) {
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * dbm_chunk_alloc
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * Allocate a chunk and return it. If the cache for the
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * chunks is not fully used, a new chunk is created.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * Otherwise, the first chunk from the LRU list is reclaimed,
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * loaded and returned.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar return (dbm_chunk_load(bmp, cp, bn, BMAP_OLD_CHUNK));
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * dbm_chunks_free
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * Release the memory allocated for the chunks.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * dbm_chunk_reposition
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * Re-position the chunk in the LRU and the hash table.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdardbm_chunk_reposition(dbitmap_t *bmp, dbmap_list_t *hp, dbmap_chunk_t *cp)
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * dbm_chunk_find
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * Find and return the chunks which holds the specified bit.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * Allocate the chunk if necessary and re-position it in the
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * LRU and hash table lists.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar if (bn >= cp->c_off && bn < (cp->c_off + cp->c_clen)) {
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * dbmp_setval
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * Set a range of bits in the bitmap specified by the
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar for (cl = cp->c_off + cp->c_clen; bn < cl && bn < max; bn++) {
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * dbmp_getval
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * Get a range of bits in the bitmap specified by the
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar for (cl = cp->c_off + cp->c_clen; bn < cl && bn < max; bn++) {
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * dbyte_apply_ifset
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * Apply the function on the set bits of the specified word.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdardbyte_apply_ifset(dbitmap_t *bmp, u_quad_t off, uint_t b, int(*fp)(),
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar if (b & 1) {
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * dbm_chunk_apply_ifset
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * Apply the function on the set bits of the specified chunk.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdardbm_chunk_apply_ifset(dbitmap_t *bmp, dbmap_chunk_t *cp, int(*fp)(),
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * swfile_trunc
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * Truncate the rest of the swap file.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * Get the current offset and truncate whatever is
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * after this point.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * swfile_init
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * Initialize the swap file. The necessary disk space is
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * reserved by writing to the swap file for swapping the
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * chunks in/out of the file.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar (void) memset(buf, set ? 0xff : 0x00, BMAP_CHUNK_BYTES);
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar for (i = 0; i < n; i++)
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar if (write(fd, buf, BMAP_CHUNK_BYTES) != BMAP_CHUNK_BYTES)
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar return (-1);
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar return (-1);
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * Allocate a bit map and return a handle to it.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * The swap file is created if it does not exist.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * The file is truncated if it exists and is larger
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * than needed amount.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * The hash table and LRU list are empty at this point.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * They are allocated and/or loaded on-demand.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar return (-1);
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * When allocating bitmap, make sure there is enough
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * disk space by allocating needed disk space, for
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * writing back the dirty chunks when swaping them out.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar if ((fd = open(fname, O_RDWR|O_CREAT, 0600)) < 0)
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * Free memory allocated for the bitmap and remove its swap file.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * dbm_getlen
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * Return length of the bitmap.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * Set a range of bits.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdardbm_set(int bmd, u_quad_t start, u_quad_t len, uint_t val)
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * dbm_getiov
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * Get bits specified by the array of vectors.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * dbm_setiov
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * Set bits specified by the array of vectors.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * dbm_apply_ifset
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * Call the callback function for each set bit in the bitmap and
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * pass the 'arg' and bit number as its argument.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar for (q = 0; q < bmp->bm_len; q += BMAP_CHUNK_BITS) {
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * Set a range of bits.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdarbm_set(int bmd, u_quad_t start, u_quad_t len, uint_t val)
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * Get a range of bits.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdarbm_get(int bmd, u_quad_t start, u_quad_t len, uint_t *buf)
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * Get only one bit.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar return (i ? 1 : 0);
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * Get a range of bits.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdardbm_get(int bmd, u_quad_t start, u_quad_t len, uint_t *buf)
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * dbm_getone
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar * Get only one bit.
2654012f83cec5dc15b61dfe3e4a4915f186e7a6Reza Sabdar return (i ? 1 : 0);