diff options
author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 |
---|---|---|
committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /drivers/infiniband/hw/mthca/mthca_allocator.c |
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'drivers/infiniband/hw/mthca/mthca_allocator.c')
-rw-r--r-- | drivers/infiniband/hw/mthca/mthca_allocator.c | 179 |
1 files changed, 179 insertions, 0 deletions
diff --git a/drivers/infiniband/hw/mthca/mthca_allocator.c b/drivers/infiniband/hw/mthca/mthca_allocator.c new file mode 100644 index 000000000000..b1db48dd91d6 --- /dev/null +++ b/drivers/infiniband/hw/mthca/mthca_allocator.c @@ -0,0 +1,179 @@ +/* + * Copyright (c) 2004 Topspin Communications. All rights reserved. + * + * This software is available to you under a choice of one of two + * licenses. You may choose to be licensed under the terms of the GNU + * General Public License (GPL) Version 2, available from the file + * COPYING in the main directory of this source tree, or the + * OpenIB.org BSD license below: + * + * Redistribution and use in source and binary forms, with or + * without modification, are permitted provided that the following + * conditions are met: + * + * - Redistributions of source code must retain the above + * copyright notice, this list of conditions and the following + * disclaimer. + * + * - Redistributions in binary form must reproduce the above + * copyright notice, this list of conditions and the following + * disclaimer in the documentation and/or other materials + * provided with the distribution. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND + * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS + * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN + * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + * + * $Id: mthca_allocator.c 1349 2004-12-16 21:09:43Z roland $ + */ + +#include <linux/errno.h> +#include <linux/slab.h> +#include <linux/bitmap.h> + +#include "mthca_dev.h" + +/* Trivial bitmap-based allocator */ +u32 mthca_alloc(struct mthca_alloc *alloc) +{ + u32 obj; + + spin_lock(&alloc->lock); + obj = find_next_zero_bit(alloc->table, alloc->max, alloc->last); + if (obj >= alloc->max) { + alloc->top = (alloc->top + alloc->max) & alloc->mask; + obj = find_first_zero_bit(alloc->table, alloc->max); + } + + if (obj < alloc->max) { + set_bit(obj, alloc->table); + obj |= alloc->top; + } else + obj = -1; + + spin_unlock(&alloc->lock); + + return obj; +} + +void mthca_free(struct mthca_alloc *alloc, u32 obj) +{ + obj &= alloc->max - 1; + spin_lock(&alloc->lock); + clear_bit(obj, alloc->table); + alloc->last = min(alloc->last, obj); + alloc->top = (alloc->top + alloc->max) & alloc->mask; + spin_unlock(&alloc->lock); +} + +int mthca_alloc_init(struct mthca_alloc *alloc, u32 num, u32 mask, + u32 reserved) +{ + int i; + + /* num must be a power of 2 */ + if (num != 1 << (ffs(num) - 1)) + return -EINVAL; + + alloc->last = 0; + alloc->top = 0; + alloc->max = num; + alloc->mask = mask; + spin_lock_init(&alloc->lock); + alloc->table = kmalloc(BITS_TO_LONGS(num) * sizeof (long), + GFP_KERNEL); + if (!alloc->table) + return -ENOMEM; + + bitmap_zero(alloc->table, num); + for (i = 0; i < reserved; ++i) + set_bit(i, alloc->table); + + return 0; +} + +void mthca_alloc_cleanup(struct mthca_alloc *alloc) +{ + kfree(alloc->table); +} + +/* + * Array of pointers with lazy allocation of leaf pages. Callers of + * _get, _set and _clear methods must use a lock or otherwise + * serialize access to the array. + */ + +void *mthca_array_get(struct mthca_array *array, int index) +{ + int p = (index * sizeof (void *)) >> PAGE_SHIFT; + + if (array->page_list[p].page) { + int i = index & (PAGE_SIZE / sizeof (void *) - 1); + return array->page_list[p].page[i]; + } else + return NULL; +} + +int mthca_array_set(struct mthca_array *array, int index, void *value) +{ + int p = (index * sizeof (void *)) >> PAGE_SHIFT; + + /* Allocate with GFP_ATOMIC because we'll be called with locks held. */ + if (!array->page_list[p].page) + array->page_list[p].page = (void **) get_zeroed_page(GFP_ATOMIC); + + if (!array->page_list[p].page) + return -ENOMEM; + + array->page_list[p].page[index & (PAGE_SIZE / sizeof (void *) - 1)] = + value; + ++array->page_list[p].used; + + return 0; +} + +void mthca_array_clear(struct mthca_array *array, int index) +{ + int p = (index * sizeof (void *)) >> PAGE_SHIFT; + + if (--array->page_list[p].used == 0) { + free_page((unsigned long) array->page_list[p].page); + array->page_list[p].page = NULL; + } + + if (array->page_list[p].used < 0) + pr_debug("Array %p index %d page %d with ref count %d < 0\n", + array, index, p, array->page_list[p].used); +} + +int mthca_array_init(struct mthca_array *array, int nent) +{ + int npage = (nent * sizeof (void *) + PAGE_SIZE - 1) / PAGE_SIZE; + int i; + + array->page_list = kmalloc(npage * sizeof *array->page_list, GFP_KERNEL); + if (!array->page_list) + return -ENOMEM; + + for (i = 0; i < npage; ++i) { + array->page_list[i].page = NULL; + array->page_list[i].used = 0; + } + + return 0; +} + +void mthca_array_cleanup(struct mthca_array *array, int nent) +{ + int i; + + for (i = 0; i < (nent * sizeof (void *) + PAGE_SIZE - 1) / PAGE_SIZE; ++i) + free_page((unsigned long) array->page_list[i].page); + + kfree(array->page_list); +} |