Ejemplo n.º 1
0
/*
 * hfs_btree_free()
 *
 * Description:
 *   This function frees a (struct hfs_btree) obtained from hfs_btree_init().
 *   Called by hfs_put_super().
 * Input Variable(s):
 *   struct hfs_btree *bt: pointer to the (struct hfs_btree) to free
 * Output Variable(s):
 *   NONE
 * Returns:
 *   void
 * Preconditions:
 *   'bt' is NULL or points to a "valid" (struct hfs_btree)
 * Postconditions:
 *   If 'bt' points to a "valid" (struct hfs_btree) then all (struct
 *    hfs_bnode)s associated with 'bt' are freed by calling
 *    hfs_bnode_ditch() and the memory associated with the (struct
 *    hfs_btree) is freed.
 *   If 'bt' is NULL or not "valid" an error is printed and nothing
 *    is changed.
 */
void hfs_btree_free(struct hfs_btree *bt)
{
	int lcv;

	if (bt && (bt->magic == HFS_BTREE_MAGIC)) {
		hfs_extent_free(&bt->entry.u.file.data_fork);

		for (lcv=0; lcv<HFS_CACHELEN; ++lcv) {
#if defined(DEBUG_BNODES) || defined(DEBUG_ALL)
			hfs_warn("deleting nodes from bucket %d:\n", lcv);
#endif
			hfs_bnode_ditch(bt->cache[lcv]);
		}

#if defined(DEBUG_BNODES) || defined(DEBUG_ALL)
		hfs_warn("deleting header and bitmap nodes\n");
#endif
		hfs_bnode_ditch(&bt->head);

#if defined(DEBUG_BNODES) || defined(DEBUG_ALL)
		hfs_warn("deleting root node\n");
#endif
		hfs_bnode_ditch(bt->root);

		HFS_DELETE(bt);
	} else if (bt) {
		hfs_warn("hfs_btree_free: corrupted hfs_btree.\n");
	}
}
Ejemplo n.º 2
0
/*
 * relse_ext()
 *
 * Reduce the reference count of an in-core extent record by one,
 * removing it from memory if the count falls to zero.
 */
static void relse_ext(struct hfs_extent *ext)
{
    if (--ext->count || !ext->start) {
        return;
    }
    ext->prev->next = ext->next;
    if (ext->next) {
        ext->next->prev = ext->prev;
    }
    HFS_DELETE(ext);
}
Ejemplo n.º 3
0
/*
 * hfs_put_inode()
 *
 * This is the put_inode() entry in the super_operations for HFS
 * filesystems.  The purpose is to perform any filesystem-dependent 
 * cleanup necessary when the use-count of an inode falls to zero.
 */
void hfs_put_inode(struct inode * inode)
{
	struct hfs_cat_entry *entry = HFS_I(inode)->entry;

	hfs_cat_put(entry);
	if (inode->i_count == 1) {
	  struct hfs_hdr_layout *tmp = HFS_I(inode)->layout;

	  if (tmp) {
		HFS_I(inode)->layout = NULL;
		HFS_DELETE(tmp);
	  }
	}
}
Ejemplo n.º 4
0
/*
 * hfs_put_inode()
 *
 * This is the put_inode() entry in the super_operations for HFS
 * filesystems.  The purpose is to perform any filesystem-dependent
 * cleanup necessary when the use-count of an inode falls to zero.
 */
void hfs_put_inode(struct inode * inode)
{
    struct hfs_cat_entry *entry = HFS_I(inode)->entry;

    lock_kernel();
    hfs_cat_put(entry);
    if (atomic_read(&inode->i_count) == 1) {
        struct hfs_hdr_layout *tmp = HFS_I(inode)->layout;

        if (tmp) {
            HFS_I(inode)->layout = NULL;
            HFS_DELETE(tmp);
        }
    }
    unlock_kernel();
}
Ejemplo n.º 5
0
/*
 * new_extent()
 *
 * Description:
 *   Adds a new extent record to a fork, extending its physical length.
 * Input Variable(s):
 *   struct hfs_fork *fork: the fork to extend
 *   struct hfs_extent *ext: the current last extent for 'fork'
 *   hfs_u16 ablock: the number of allocation blocks in 'fork'.
 *   hfs_u16 start: first allocation block to add to 'fork'.
 *   hfs_u16 len: the number of allocation blocks to add to 'fork'.
 *   hfs_u32 ablksz: number of sectors in an allocation block.
 * Output Variable(s):
 *   NONE
 * Returns:
 *   (struct hfs_extent *) the new extent or NULL
 * Preconditions:
 *   'fork' points to a valid (struct hfs_fork)
 *   'ext' point to a valid (struct hfs_extent) which is the last in 'fork'
 *   'ablock', 'start', 'len' and 'ablksz' are what they claim to be.
 * Postconditions:
 *   If NULL is returned then no changes have been made to 'fork'.
 *   If the return value is non-NULL that it is the extent that has been
 *   added to 'fork' both in memory and on disk.  The 'psize' field of
 *   'fork' has been updated to reflect the new physical size.
 */
static struct hfs_extent *new_extent(struct hfs_fork *fork,
                                     struct hfs_extent *ext,
                                     hfs_u16 ablock, hfs_u16 start,
                                     hfs_u16 len, hfs_u16 ablksz)
{
    struct hfs_raw_extent raw;
    struct hfs_ext_key key;
    int error;

    if (fork->entry->cnid == htonl(HFS_EXT_CNID)) {
        /* Limit extents tree to the record in the MDB */
        return NULL;
    }

    if (!HFS_NEW(ext->next)) {
        return NULL;
    }
    ext->next->prev = ext;
    ext->next->next = NULL;
    ext = ext->next;
    relse_ext(ext->prev);

    ext->start = ablock;
    ext->block[0] = start;
    ext->length[0] = len;
    ext->block[1] = 0;
    ext->length[1] = 0;
    ext->block[2] = 0;
    ext->length[2] = 0;
    ext->end = ablock + len - 1;
    ext->count = 1;

    write_extent(&raw, ext);

    build_key(&key, fork, ablock);

    error = hfs_binsert(fork->entry->mdb->ext_tree,
                        HFS_BKEY(&key), &raw, sizeof(raw));
    if (error) {
        ext->prev->next = NULL;
        HFS_DELETE(ext);
        return NULL;
    }
    set_cache(fork, ext);
    return ext;
}
Ejemplo n.º 6
0
/*
 * hfs_bnode_ditch() 
 *
 * Description:
 *   This function deletes an entire linked list of bnodes, so it
 *   does not need to keep the linked list consistent as
 *   hfs_bnode_delete() does.
 *   Called by hfs_btree_init() for error cleanup and by hfs_btree_free().
 * Input Variable(s):
 *   struct hfs_bnode *bn: pointer to the first (struct hfs_bnode) in
 *    the linked list to be deleted.
 * Output Variable(s):
 *   NONE
 * Returns:
 *   void
 * Preconditions:
 *   'bn' is NULL or points to a "valid" (struct hfs_bnode) with a 'prev'
 *    field of NULL.
 * Postconditions:
 *   'bn' and all (struct hfs_bnode)s in the chain of 'next' pointers
 *   are deleted, freeing the associated memory and hfs_buffer_put()ing
 *   the associated buffer.
 */
static void hfs_bnode_ditch(struct hfs_bnode *bn) {
	struct hfs_bnode *tmp;
#if defined(DEBUG_BNODES) || defined(DEBUG_ALL)
	extern int bnode_count;
#endif

	while (bn != NULL) {
		tmp = bn->next;
#if defined(DEBUG_BNODES) || defined(DEBUG_ALL)
		hfs_warn("deleting node %d from tree %d with count %d\n",
		         bn->node, (int)ntohl(bn->tree->entry.cnid), bn->count);
		--bnode_count;
#endif
		hfs_buffer_put(bn->buf); /* safe: checks for NULL argument */

		/* free all but the header */
		if (bn->node) {
			HFS_DELETE(bn);
		}
		bn = tmp;
	}
}
Ejemplo n.º 7
0
/*
 * delete_extent()
 *
 * Description:
 *   Deletes an extent record from a fork, reducing its physical length.
 * Input Variable(s):
 *   struct hfs_fork *fork: the fork
 *   struct hfs_extent *ext: the current last extent for 'fork'
 * Output Variable(s):
 *   NONE
 * Returns:
 *   void
 * Preconditions:
 *   'fork' points to a valid (struct hfs_fork)
 *   'ext' point to a valid (struct hfs_extent) which is the last in 'fork'
 *    and which is not also the first extent in 'fork'.
 * Postconditions:
 *   The extent record has been removed if possible, and a warning has been
 *   printed otherwise.
 */
static void delete_extent(struct hfs_fork *fork, struct hfs_extent *ext)
{
    struct hfs_mdb *mdb = fork->entry->mdb;
    struct hfs_ext_key key;
    int error;

    if (fork->cache == ext) {
        set_cache(fork, ext->prev);
    }
    ext->prev->next = NULL;
    if (ext->count != 1) {
        hfs_warn("hfs_truncate: extent has count %d.\n", ext->count);
    }

    lock_bitmap(mdb);
    error = hfs_clear_vbm_bits(mdb, ext->block[2], ext->length[2]);
    if (error) {
        hfs_warn("hfs_truncate: error %d freeing blocks.\n", error);
    }
    error = hfs_clear_vbm_bits(mdb, ext->block[1], ext->length[1]);
    if (error) {
        hfs_warn("hfs_truncate: error %d freeing blocks.\n", error);
    }
    error = hfs_clear_vbm_bits(mdb, ext->block[0], ext->length[0]);
    if (error) {
        hfs_warn("hfs_truncate: error %d freeing blocks.\n", error);
    }
    unlock_bitmap(mdb);

    build_key(&key, fork, ext->start);

    error = hfs_bdelete(mdb->ext_tree, HFS_BKEY(&key));
    if (error) {
        hfs_warn("hfs_truncate: error %d deleting an extent.\n", error);
    }

    HFS_DELETE(ext);
}
Ejemplo n.º 8
0
/*
 * hfs_btree_init()
 *
 * Description:
 *   Given some vital information from the MDB (HFS superblock),
 *   initializes the fields of a (struct hfs_btree).
 * Input Variable(s):
 *   struct hfs_mdb *mdb: pointer to the MDB
 *   ino_t cnid: the CNID (HFS_CAT_CNID or HFS_EXT_CNID) of the B-tree
 *   hfs_u32 tsize: the size, in bytes, of the B-tree
 *   hfs_u32 csize: the size, in bytes, of the clump size for the B-tree
 * Output Variable(s):
 *   NONE
 * Returns:
 *   (struct hfs_btree *): pointer to the initialized hfs_btree on success,
 *    or NULL on failure
 * Preconditions:
 *   'mdb' points to a "valid" (struct hfs_mdb)
 * Postconditions:
 *   Assuming the inputs are what they claim to be, no errors occur
 *   reading from disk, and no inconsistencies are noticed in the data
 *   read from disk, the return value is a pointer to a "valid"
 *   (struct hfs_btree).  If there are errors reading from disk or
 *   inconsistencies are noticed in the data read from disk, then and
 *   all resources that were allocated are released and NULL is
 *   returned.	If the inputs are not what they claim to be or if they
 *   are unnoticed inconsistencies in the data read from disk then the
 *   returned hfs_btree is probably going to lead to errors when it is
 *   used in a non-trivial way.
 */
struct hfs_btree * hfs_btree_init(struct hfs_mdb *mdb, ino_t cnid,
				  hfs_byte_t ext[12],
				  hfs_u32 tsize, hfs_u32 csize)
{
	struct hfs_btree * bt;
	struct BTHdrRec * th;
	struct hfs_bnode * tmp;
	unsigned int next;
#if defined(DEBUG_HEADER) || defined(DEBUG_ALL)
	unsigned char *p, *q;
#endif

	if (!mdb || !ext || !HFS_NEW(bt)) {
		goto bail3;
	}

	bt->magic = HFS_BTREE_MAGIC;
	bt->sys_mdb = mdb->sys_mdb;
	bt->reserved = 0;
	bt->lock = 0;
	hfs_init_waitqueue(&bt->wait);
	bt->dirt = 0;
	memset(bt->cache, 0, sizeof(bt->cache));

#if 0   /* this is a fake entry. so we don't need to initialize it. */
	memset(&bt->entry, 0, sizeof(bt->entry));
	hfs_init_waitqueue(&bt->entry.wait);
	INIT_LIST_HEAD(&bt->entry.hash);
	INIT_LIST_HEAD(&bt->entry.list);
#endif

	bt->entry.mdb = mdb;
	bt->entry.cnid = cnid;
	bt->entry.type = HFS_CDR_FIL;
	bt->entry.u.file.magic = HFS_FILE_MAGIC;
	bt->entry.u.file.clumpablks = (csize / mdb->alloc_blksz)
						>> HFS_SECTOR_SIZE_BITS;
	bt->entry.u.file.data_fork.entry = &bt->entry;
	bt->entry.u.file.data_fork.lsize = tsize;
	bt->entry.u.file.data_fork.psize = tsize >> HFS_SECTOR_SIZE_BITS;
	bt->entry.u.file.data_fork.fork = HFS_FK_DATA;
	hfs_extent_in(&bt->entry.u.file.data_fork, ext);

	hfs_bnode_read(&bt->head, bt, 0, HFS_STICKY);
	if (!hfs_buffer_ok(bt->head.buf)) {
		goto bail2;
	}
	th = (struct BTHdrRec *)((char *)hfs_buffer_data(bt->head.buf) +
						sizeof(struct NodeDescriptor));

	/* read in the bitmap nodes (if any) */
	tmp = &bt->head;
	while ((next = tmp->ndFLink)) {
		if (!HFS_NEW(tmp->next)) {
			goto bail2;
		}
		hfs_bnode_read(tmp->next, bt, next, HFS_STICKY);
		if (!hfs_buffer_ok(tmp->next->buf)) {
			goto bail2;
		}
		tmp->next->prev = tmp;
		tmp = tmp->next;
	}

	if (hfs_get_ns(th->bthNodeSize) != htons(HFS_SECTOR_SIZE)) {
		hfs_warn("hfs_btree_init: bthNodeSize!=512 not supported\n");
		goto bail2;
	}

	if (cnid == htonl(HFS_CAT_CNID)) {
		bt->compare = (hfs_cmpfn)hfs_cat_compare;
	} else if (cnid == htonl(HFS_EXT_CNID)) {
		bt->compare = (hfs_cmpfn)hfs_ext_compare;
	} else {
		goto bail2;
	}
	bt->bthDepth  = hfs_get_hs(th->bthDepth);
	bt->bthRoot   = hfs_get_hl(th->bthRoot);
	bt->bthNRecs  = hfs_get_hl(th->bthNRecs);
	bt->bthFNode  = hfs_get_hl(th->bthFNode);
	bt->bthLNode  = hfs_get_hl(th->bthLNode);
	bt->bthNNodes = hfs_get_hl(th->bthNNodes);
	bt->bthFree   = hfs_get_hl(th->bthFree);
	bt->bthKeyLen = hfs_get_hs(th->bthKeyLen);

#if defined(DEBUG_HEADER) || defined(DEBUG_ALL)
	hfs_warn("bthDepth %d\n", bt->bthDepth);
	hfs_warn("bthRoot %d\n", bt->bthRoot);
	hfs_warn("bthNRecs %d\n", bt->bthNRecs);
	hfs_warn("bthFNode %d\n", bt->bthFNode);
	hfs_warn("bthLNode %d\n", bt->bthLNode);
	hfs_warn("bthKeyLen %d\n", bt->bthKeyLen);
	hfs_warn("bthNNodes %d\n", bt->bthNNodes);
	hfs_warn("bthFree %d\n", bt->bthFree);
	p = (unsigned char *)hfs_buffer_data(bt->head.buf);
	q = p + HFS_SECTOR_SIZE;
	while (p < q) {
		hfs_warn("%02x %02x %02x %02x %02x %02x %02x %02x "
		         "%02x %02x %02x %02x %02x %02x %02x %02x\n",
			 *p++, *p++, *p++, *p++, *p++, *p++, *p++, *p++,
			 *p++, *p++, *p++, *p++, *p++, *p++, *p++, *p++);
	}
#endif

	/* Read in the root if it exists.
	   The header always exists, but the root exists only if the
	   tree is non-empty */
	if (bt->bthDepth && bt->bthRoot) {
		if (!HFS_NEW(bt->root)) {
			goto bail2;
		}
		hfs_bnode_read(bt->root, bt, bt->bthRoot, HFS_STICKY);
		if (!hfs_buffer_ok(bt->root->buf)) {
			goto bail1;
		}
	} else {
		bt->root = NULL;
	}

	return bt;

 bail1:
	hfs_bnode_ditch(bt->root);
 bail2:
	hfs_bnode_ditch(&bt->head);
	HFS_DELETE(bt);
 bail3:
	return NULL;
}
Ejemplo n.º 9
0
/*
 * find_ext()
 *
 * Given a pointer to a (struct hfs_file) and an allocation block
 * number in the file, find the extent record containing that block.
 * Returns a pointer to the extent record on success or NULL on failure.
 * The 'cache' field of 'fil' also points to the extent so it has a
 * reference count of at least 2.
 *
 * Callers must check that fil != NULL
 */
static struct hfs_extent * find_ext(struct hfs_fork *fork, int alloc_block)
{
    struct hfs_cat_entry *entry = fork->entry;
    struct hfs_btree *tr= entry->mdb->ext_tree;
    struct hfs_ext_key target, *key;
    struct hfs_brec brec;
    struct hfs_extent *ext, *ptr;
    int tmp;

    if (alloc_block < 0) {
        ext = &fork->first;
        goto found;
    }

    ext = fork->cache;
    if (!ext || (alloc_block < ext->start)) {
        ext = &fork->first;
    }
    while (ext->next && (alloc_block > ext->end)) {
        ext = ext->next;
    }
    if ((alloc_block <= ext->end) && (alloc_block >= ext->start)) {
        goto found;
    }

    /* time to read more extents */
    if (!HFS_NEW(ext)) {
        goto bail3;
    }

    build_key(&target, fork, alloc_block);

    tmp = hfs_bfind(&brec, tr, HFS_BKEY(&target), HFS_BFIND_READ_LE);
    if (tmp < 0) {
        goto bail2;
    }

    key = (struct hfs_ext_key *)brec.key;
    if ((hfs_get_nl(key->FNum) != hfs_get_nl(target.FNum)) ||
            (key->FkType != fork->fork)) {
        goto bail1;
    }

    read_extent(ext, brec.data, hfs_get_hs(key->FABN));
    hfs_brec_relse(&brec, NULL);

    if ((alloc_block > ext->end) && (alloc_block < ext->start)) {
        /* something strange happened */
        goto bail2;
    }

    ptr = fork->cache;
    if (!ptr || (alloc_block < ptr->start)) {
        ptr = &fork->first;
    }
    while (ptr->next && (alloc_block > ptr->end)) {
        ptr = ptr->next;
    }
    if (ext->start == ptr->start) {
        /* somebody beat us to it. */
        HFS_DELETE(ext);
        ext = ptr;
    } else if (ext->start < ptr->start) {
        /* insert just before ptr */
        ptr->prev->next = ext;
        ext->prev = ptr->prev;
        ext->next = ptr;
        ptr->prev = ext;
    } else {
        /* insert at end */
        ptr->next = ext;
        ext->prev = ptr;
    }
found:
    ++ext->count; /* for return value */
    set_cache(fork, ext);
    return ext;

bail1:
    hfs_brec_relse(&brec, NULL);
bail2:
    HFS_DELETE(ext);
bail3:
    return NULL;
}