treewide: remove redundant IS_ERR() before error code check
[linux/fpc-iii.git] / drivers / infiniband / hw / mthca / mthca_mcg.c
blob6304ae8f4a6cc0d300e1677c57dc9defc087a485
1 /*
2 * Copyright (c) 2004 Topspin Communications. All rights reserved.
4 * This software is available to you under a choice of one of two
5 * licenses. You may choose to be licensed under the terms of the GNU
6 * General Public License (GPL) Version 2, available from the file
7 * COPYING in the main directory of this source tree, or the
8 * OpenIB.org BSD license below:
10 * Redistribution and use in source and binary forms, with or
11 * without modification, are permitted provided that the following
12 * conditions are met:
14 * - Redistributions of source code must retain the above
15 * copyright notice, this list of conditions and the following
16 * disclaimer.
18 * - Redistributions in binary form must reproduce the above
19 * copyright notice, this list of conditions and the following
20 * disclaimer in the documentation and/or other materials
21 * provided with the distribution.
23 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
24 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
25 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
26 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
27 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
28 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
29 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
30 * SOFTWARE.
33 #include <linux/string.h>
34 #include <linux/gfp.h>
36 #include "mthca_dev.h"
37 #include "mthca_cmd.h"
39 struct mthca_mgm {
40 __be32 next_gid_index;
41 u32 reserved[3];
42 u8 gid[16];
43 __be32 qp[MTHCA_QP_PER_MGM];
46 static const u8 zero_gid[16]; /* automatically initialized to 0 */
49 * Caller must hold MCG table semaphore. gid and mgm parameters must
50 * be properly aligned for command interface.
52 * Returns 0 unless a firmware command error occurs.
54 * If GID is found in MGM or MGM is empty, *index = *hash, *prev = -1
55 * and *mgm holds MGM entry.
57 * if GID is found in AMGM, *index = index in AMGM, *prev = index of
58 * previous entry in hash chain and *mgm holds AMGM entry.
60 * If no AMGM exists for given gid, *index = -1, *prev = index of last
61 * entry in hash chain and *mgm holds end of hash chain.
63 static int find_mgm(struct mthca_dev *dev,
64 u8 *gid, struct mthca_mailbox *mgm_mailbox,
65 u16 *hash, int *prev, int *index)
67 struct mthca_mailbox *mailbox;
68 struct mthca_mgm *mgm = mgm_mailbox->buf;
69 u8 *mgid;
70 int err;
72 mailbox = mthca_alloc_mailbox(dev, GFP_KERNEL);
73 if (IS_ERR(mailbox))
74 return -ENOMEM;
75 mgid = mailbox->buf;
77 memcpy(mgid, gid, 16);
79 err = mthca_MGID_HASH(dev, mailbox, hash);
80 if (err) {
81 mthca_err(dev, "MGID_HASH failed (%d)\n", err);
82 goto out;
85 if (0)
86 mthca_dbg(dev, "Hash for %pI6 is %04x\n", gid, *hash);
88 *index = *hash;
89 *prev = -1;
91 do {
92 err = mthca_READ_MGM(dev, *index, mgm_mailbox);
93 if (err) {
94 mthca_err(dev, "READ_MGM failed (%d)\n", err);
95 goto out;
98 if (!memcmp(mgm->gid, zero_gid, 16)) {
99 if (*index != *hash) {
100 mthca_err(dev, "Found zero MGID in AMGM.\n");
101 err = -EINVAL;
103 goto out;
106 if (!memcmp(mgm->gid, gid, 16))
107 goto out;
109 *prev = *index;
110 *index = be32_to_cpu(mgm->next_gid_index) >> 6;
111 } while (*index);
113 *index = -1;
115 out:
116 mthca_free_mailbox(dev, mailbox);
117 return err;
120 int mthca_multicast_attach(struct ib_qp *ibqp, union ib_gid *gid, u16 lid)
122 struct mthca_dev *dev = to_mdev(ibqp->device);
123 struct mthca_mailbox *mailbox;
124 struct mthca_mgm *mgm;
125 u16 hash;
126 int index, prev;
127 int link = 0;
128 int i;
129 int err;
131 mailbox = mthca_alloc_mailbox(dev, GFP_KERNEL);
132 if (IS_ERR(mailbox))
133 return PTR_ERR(mailbox);
134 mgm = mailbox->buf;
136 mutex_lock(&dev->mcg_table.mutex);
138 err = find_mgm(dev, gid->raw, mailbox, &hash, &prev, &index);
139 if (err)
140 goto out;
142 if (index != -1) {
143 if (!memcmp(mgm->gid, zero_gid, 16))
144 memcpy(mgm->gid, gid->raw, 16);
145 } else {
146 link = 1;
148 index = mthca_alloc(&dev->mcg_table.alloc);
149 if (index == -1) {
150 mthca_err(dev, "No AMGM entries left\n");
151 err = -ENOMEM;
152 goto out;
155 err = mthca_READ_MGM(dev, index, mailbox);
156 if (err) {
157 mthca_err(dev, "READ_MGM failed (%d)\n", err);
158 goto out;
160 memset(mgm, 0, sizeof *mgm);
161 memcpy(mgm->gid, gid->raw, 16);
164 for (i = 0; i < MTHCA_QP_PER_MGM; ++i)
165 if (mgm->qp[i] == cpu_to_be32(ibqp->qp_num | (1 << 31))) {
166 mthca_dbg(dev, "QP %06x already a member of MGM\n",
167 ibqp->qp_num);
168 err = 0;
169 goto out;
170 } else if (!(mgm->qp[i] & cpu_to_be32(1 << 31))) {
171 mgm->qp[i] = cpu_to_be32(ibqp->qp_num | (1 << 31));
172 break;
175 if (i == MTHCA_QP_PER_MGM) {
176 mthca_err(dev, "MGM at index %x is full.\n", index);
177 err = -ENOMEM;
178 goto out;
181 err = mthca_WRITE_MGM(dev, index, mailbox);
182 if (err) {
183 mthca_err(dev, "WRITE_MGM failed %d\n", err);
184 err = -EINVAL;
185 goto out;
188 if (!link)
189 goto out;
191 err = mthca_READ_MGM(dev, prev, mailbox);
192 if (err) {
193 mthca_err(dev, "READ_MGM failed %d\n", err);
194 goto out;
197 mgm->next_gid_index = cpu_to_be32(index << 6);
199 err = mthca_WRITE_MGM(dev, prev, mailbox);
200 if (err)
201 mthca_err(dev, "WRITE_MGM returned %d\n", err);
203 out:
204 if (err && link && index != -1) {
205 BUG_ON(index < dev->limits.num_mgms);
206 mthca_free(&dev->mcg_table.alloc, index);
208 mutex_unlock(&dev->mcg_table.mutex);
210 mthca_free_mailbox(dev, mailbox);
211 return err;
214 int mthca_multicast_detach(struct ib_qp *ibqp, union ib_gid *gid, u16 lid)
216 struct mthca_dev *dev = to_mdev(ibqp->device);
217 struct mthca_mailbox *mailbox;
218 struct mthca_mgm *mgm;
219 u16 hash;
220 int prev, index;
221 int i, loc;
222 int err;
224 mailbox = mthca_alloc_mailbox(dev, GFP_KERNEL);
225 if (IS_ERR(mailbox))
226 return PTR_ERR(mailbox);
227 mgm = mailbox->buf;
229 mutex_lock(&dev->mcg_table.mutex);
231 err = find_mgm(dev, gid->raw, mailbox, &hash, &prev, &index);
232 if (err)
233 goto out;
235 if (index == -1) {
236 mthca_err(dev, "MGID %pI6 not found\n", gid->raw);
237 err = -EINVAL;
238 goto out;
241 for (loc = -1, i = 0; i < MTHCA_QP_PER_MGM; ++i) {
242 if (mgm->qp[i] == cpu_to_be32(ibqp->qp_num | (1 << 31)))
243 loc = i;
244 if (!(mgm->qp[i] & cpu_to_be32(1 << 31)))
245 break;
248 if (loc == -1) {
249 mthca_err(dev, "QP %06x not found in MGM\n", ibqp->qp_num);
250 err = -EINVAL;
251 goto out;
254 mgm->qp[loc] = mgm->qp[i - 1];
255 mgm->qp[i - 1] = 0;
257 err = mthca_WRITE_MGM(dev, index, mailbox);
258 if (err) {
259 mthca_err(dev, "WRITE_MGM returned %d\n", err);
260 goto out;
263 if (i != 1)
264 goto out;
266 if (prev == -1) {
267 /* Remove entry from MGM */
268 int amgm_index_to_free = be32_to_cpu(mgm->next_gid_index) >> 6;
269 if (amgm_index_to_free) {
270 err = mthca_READ_MGM(dev, amgm_index_to_free,
271 mailbox);
272 if (err) {
273 mthca_err(dev, "READ_MGM returned %d\n", err);
274 goto out;
276 } else
277 memset(mgm->gid, 0, 16);
279 err = mthca_WRITE_MGM(dev, index, mailbox);
280 if (err) {
281 mthca_err(dev, "WRITE_MGM returned %d\n", err);
282 goto out;
284 if (amgm_index_to_free) {
285 BUG_ON(amgm_index_to_free < dev->limits.num_mgms);
286 mthca_free(&dev->mcg_table.alloc, amgm_index_to_free);
288 } else {
289 /* Remove entry from AMGM */
290 int curr_next_index = be32_to_cpu(mgm->next_gid_index) >> 6;
291 err = mthca_READ_MGM(dev, prev, mailbox);
292 if (err) {
293 mthca_err(dev, "READ_MGM returned %d\n", err);
294 goto out;
297 mgm->next_gid_index = cpu_to_be32(curr_next_index << 6);
299 err = mthca_WRITE_MGM(dev, prev, mailbox);
300 if (err) {
301 mthca_err(dev, "WRITE_MGM returned %d\n", err);
302 goto out;
304 BUG_ON(index < dev->limits.num_mgms);
305 mthca_free(&dev->mcg_table.alloc, index);
308 out:
309 mutex_unlock(&dev->mcg_table.mutex);
311 mthca_free_mailbox(dev, mailbox);
312 return err;
315 int mthca_init_mcg_table(struct mthca_dev *dev)
317 int err;
318 int table_size = dev->limits.num_mgms + dev->limits.num_amgms;
320 err = mthca_alloc_init(&dev->mcg_table.alloc,
321 table_size,
322 table_size - 1,
323 dev->limits.num_mgms);
324 if (err)
325 return err;
327 mutex_init(&dev->mcg_table.mutex);
329 return 0;
332 void mthca_cleanup_mcg_table(struct mthca_dev *dev)
334 mthca_alloc_cleanup(&dev->mcg_table.alloc);