1/*
2** z2ram - Amiga pseudo-driver to access 16bit-RAM in ZorroII space
3** as a block device, to be used as a RAM disk or swap space
4**
5** Copyright (C) 1994 by Ingo Wilken (Ingo.Wilken@informatik.uni-oldenburg.de)
6**
7** ++Geert: support for zorro_unused_z2ram, better range checking
8** ++roman: translate accesses via an array
9** ++Milan: support for ChipRAM usage
10** ++yambo: converted to 2.0 kernel
11** ++yambo: modularized and support added for 3 minor devices including:
12** MAJOR MINOR DESCRIPTION
13** ----- ----- ----------------------------------------------
14** 37 0 Use Zorro II and Chip ram
15** 37 1 Use only Zorro II ram
16** 37 2 Use only Chip ram
17** 37 4-7 Use memory list entry 1-4 (first is 0)
18** ++jskov: support for 1-4th memory list entry.
19**
20** Permission to use, copy, modify, and distribute this software and its
21** documentation for any purpose and without fee is hereby granted, provided
22** that the above copyright notice appear in all copies and that both that
23** copyright notice and this permission notice appear in supporting
24** documentation. This software is provided "as is" without express or
25** implied warranty.
26*/
27
28#define DEVICE_NAME "Z2RAM"
29
30#include <linux/major.h>
31#include <linux/vmalloc.h>
32#include <linux/init.h>
33#include <linux/module.h>
34#include <linux/blk-mq.h>
35#include <linux/bitops.h>
36#include <linux/mutex.h>
37#include <linux/slab.h>
38#include <linux/pgtable.h>
39
40#include <asm/setup.h>
41#include <asm/amigahw.h>
42
43#include <linux/zorro.h>
44
45#define Z2MINOR_COMBINED (0)
46#define Z2MINOR_Z2ONLY (1)
47#define Z2MINOR_CHIPONLY (2)
48#define Z2MINOR_MEMLIST1 (4)
49#define Z2MINOR_MEMLIST2 (5)
50#define Z2MINOR_MEMLIST3 (6)
51#define Z2MINOR_MEMLIST4 (7)
52#define Z2MINOR_COUNT (8) /* Move this down when adding a new minor */
53
54#define Z2RAM_CHUNK1024 ( Z2RAM_CHUNKSIZE >> 10 )
55
56static DEFINE_MUTEX(z2ram_mutex);
57static u_long *z2ram_map = NULL;
58static u_long z2ram_size = 0;
59static int z2_count = 0;
60static int chip_count = 0;
61static int list_count = 0;
62static int current_device = -1;
63
64static DEFINE_SPINLOCK(z2ram_lock);
65
66static struct gendisk *z2ram_gendisk[Z2MINOR_COUNT];
67
68static blk_status_t z2_queue_rq(struct blk_mq_hw_ctx *hctx,
69 const struct blk_mq_queue_data *bd)
70{
71 struct request *req = bd->rq;
72 unsigned long start = blk_rq_pos(rq: req) << 9;
73 unsigned long len = blk_rq_cur_bytes(rq: req);
74
75 blk_mq_start_request(rq: req);
76
77 if (start + len > z2ram_size) {
78 pr_err(DEVICE_NAME ": bad access: block=%llu, "
79 "count=%u\n",
80 (unsigned long long)blk_rq_pos(req),
81 blk_rq_cur_sectors(req));
82 return BLK_STS_IOERR;
83 }
84
85 spin_lock_irq(lock: &z2ram_lock);
86
87 while (len) {
88 unsigned long addr = start & Z2RAM_CHUNKMASK;
89 unsigned long size = Z2RAM_CHUNKSIZE - addr;
90 void *buffer = bio_data(bio: req->bio);
91
92 if (len < size)
93 size = len;
94 addr += z2ram_map[start >> Z2RAM_CHUNKSHIFT];
95 if (rq_data_dir(req) == READ)
96 memcpy(buffer, (char *)addr, size);
97 else
98 memcpy((char *)addr, buffer, size);
99 start += size;
100 len -= size;
101 }
102
103 spin_unlock_irq(lock: &z2ram_lock);
104 blk_mq_end_request(rq: req, BLK_STS_OK);
105 return BLK_STS_OK;
106}
107
108static void get_z2ram(void)
109{
110 int i;
111
112 for (i = 0; i < Z2RAM_SIZE / Z2RAM_CHUNKSIZE; i++) {
113 if (test_bit(i, zorro_unused_z2ram)) {
114 z2_count++;
115 z2ram_map[z2ram_size++] =
116 (unsigned long)ZTWO_VADDR(Z2RAM_START) +
117 (i << Z2RAM_CHUNKSHIFT);
118 clear_bit(nr: i, addr: zorro_unused_z2ram);
119 }
120 }
121
122 return;
123}
124
125static void get_chipram(void)
126{
127
128 while (amiga_chip_avail() > (Z2RAM_CHUNKSIZE * 4)) {
129 chip_count++;
130 z2ram_map[z2ram_size] =
131 (u_long) amiga_chip_alloc(Z2RAM_CHUNKSIZE, "z2ram");
132
133 if (z2ram_map[z2ram_size] == 0) {
134 break;
135 }
136
137 z2ram_size++;
138 }
139
140 return;
141}
142
143static int z2_open(struct gendisk *disk, blk_mode_t mode)
144{
145 int device = disk->first_minor;
146 int max_z2_map = (Z2RAM_SIZE / Z2RAM_CHUNKSIZE) * sizeof(z2ram_map[0]);
147 int max_chip_map = (amiga_chip_size / Z2RAM_CHUNKSIZE) *
148 sizeof(z2ram_map[0]);
149 int rc = -ENOMEM;
150
151 mutex_lock(&z2ram_mutex);
152 if (current_device != -1 && current_device != device) {
153 rc = -EBUSY;
154 goto err_out;
155 }
156
157 if (current_device == -1) {
158 z2_count = 0;
159 chip_count = 0;
160 list_count = 0;
161 z2ram_size = 0;
162
163 /* Use a specific list entry. */
164 if (device >= Z2MINOR_MEMLIST1 && device <= Z2MINOR_MEMLIST4) {
165 int index = device - Z2MINOR_MEMLIST1 + 1;
166 unsigned long size, paddr, vaddr;
167
168 if (index >= m68k_realnum_memory) {
169 printk(KERN_ERR DEVICE_NAME
170 ": no such entry in z2ram_map\n");
171 goto err_out;
172 }
173
174 paddr = m68k_memory[index].addr;
175 size = m68k_memory[index].size & ~(Z2RAM_CHUNKSIZE - 1);
176
177#ifdef __powerpc__
178 /* FIXME: ioremap doesn't build correct memory tables. */
179 {
180 vfree(vmalloc(size));
181 }
182
183 vaddr = (unsigned long)ioremap_wt(paddr, size);
184
185#else
186 vaddr =
187 (unsigned long)z_remap_nocache_nonser(paddr, size);
188#endif
189 z2ram_map =
190 kmalloc_array(size / Z2RAM_CHUNKSIZE,
191 sizeof(z2ram_map[0]), GFP_KERNEL);
192 if (z2ram_map == NULL) {
193 printk(KERN_ERR DEVICE_NAME
194 ": cannot get mem for z2ram_map\n");
195 goto err_out;
196 }
197
198 while (size) {
199 z2ram_map[z2ram_size++] = vaddr;
200 size -= Z2RAM_CHUNKSIZE;
201 vaddr += Z2RAM_CHUNKSIZE;
202 list_count++;
203 }
204
205 if (z2ram_size != 0)
206 printk(KERN_INFO DEVICE_NAME
207 ": using %iK List Entry %d Memory\n",
208 list_count * Z2RAM_CHUNK1024, index);
209 } else
210 switch (device) {
211 case Z2MINOR_COMBINED:
212
213 z2ram_map =
214 kmalloc(max_z2_map + max_chip_map,
215 GFP_KERNEL);
216 if (z2ram_map == NULL) {
217 printk(KERN_ERR DEVICE_NAME
218 ": cannot get mem for z2ram_map\n");
219 goto err_out;
220 }
221
222 get_z2ram();
223 get_chipram();
224
225 if (z2ram_size != 0)
226 printk(KERN_INFO DEVICE_NAME
227 ": using %iK Zorro II RAM and %iK Chip RAM (Total %dK)\n",
228 z2_count * Z2RAM_CHUNK1024,
229 chip_count * Z2RAM_CHUNK1024,
230 (z2_count +
231 chip_count) * Z2RAM_CHUNK1024);
232
233 break;
234
235 case Z2MINOR_Z2ONLY:
236 z2ram_map = kmalloc(max_z2_map, GFP_KERNEL);
237 if (!z2ram_map)
238 goto err_out;
239
240 get_z2ram();
241
242 if (z2ram_size != 0)
243 printk(KERN_INFO DEVICE_NAME
244 ": using %iK of Zorro II RAM\n",
245 z2_count * Z2RAM_CHUNK1024);
246
247 break;
248
249 case Z2MINOR_CHIPONLY:
250 z2ram_map = kmalloc(max_chip_map, GFP_KERNEL);
251 if (!z2ram_map)
252 goto err_out;
253
254 get_chipram();
255
256 if (z2ram_size != 0)
257 printk(KERN_INFO DEVICE_NAME
258 ": using %iK Chip RAM\n",
259 chip_count * Z2RAM_CHUNK1024);
260
261 break;
262
263 default:
264 rc = -ENODEV;
265 goto err_out;
266
267 break;
268 }
269
270 if (z2ram_size == 0) {
271 printk(KERN_NOTICE DEVICE_NAME
272 ": no unused ZII/Chip RAM found\n");
273 goto err_out_kfree;
274 }
275
276 current_device = device;
277 z2ram_size <<= Z2RAM_CHUNKSHIFT;
278 set_capacity(disk: z2ram_gendisk[device], size: z2ram_size >> 9);
279 }
280
281 mutex_unlock(lock: &z2ram_mutex);
282 return 0;
283
284err_out_kfree:
285 kfree(objp: z2ram_map);
286err_out:
287 mutex_unlock(lock: &z2ram_mutex);
288 return rc;
289}
290
291static void z2_release(struct gendisk *disk)
292{
293 mutex_lock(&z2ram_mutex);
294 if (current_device == -1) {
295 mutex_unlock(lock: &z2ram_mutex);
296 return;
297 }
298 mutex_unlock(lock: &z2ram_mutex);
299 /*
300 * FIXME: unmap memory
301 */
302}
303
304static const struct block_device_operations z2_fops = {
305 .owner = THIS_MODULE,
306 .open = z2_open,
307 .release = z2_release,
308};
309
310static struct blk_mq_tag_set tag_set;
311
312static const struct blk_mq_ops z2_mq_ops = {
313 .queue_rq = z2_queue_rq,
314};
315
316static int z2ram_register_disk(int minor)
317{
318 struct gendisk *disk;
319 int err;
320
321 disk = blk_mq_alloc_disk(&tag_set, NULL, NULL);
322 if (IS_ERR(ptr: disk))
323 return PTR_ERR(ptr: disk);
324
325 disk->major = Z2RAM_MAJOR;
326 disk->first_minor = minor;
327 disk->minors = 1;
328 disk->flags |= GENHD_FL_NO_PART;
329 disk->fops = &z2_fops;
330 if (minor)
331 sprintf(buf: disk->disk_name, fmt: "z2ram%d", minor);
332 else
333 sprintf(buf: disk->disk_name, fmt: "z2ram");
334
335 z2ram_gendisk[minor] = disk;
336 err = add_disk(disk);
337 if (err)
338 put_disk(disk);
339 return err;
340}
341
342static int __init z2_init(void)
343{
344 int ret, i;
345
346 if (!MACH_IS_AMIGA)
347 return -ENODEV;
348
349 if (register_blkdev(Z2RAM_MAJOR, DEVICE_NAME))
350 return -EBUSY;
351
352 tag_set.ops = &z2_mq_ops;
353 tag_set.nr_hw_queues = 1;
354 tag_set.nr_maps = 1;
355 tag_set.queue_depth = 16;
356 tag_set.numa_node = NUMA_NO_NODE;
357 ret = blk_mq_alloc_tag_set(set: &tag_set);
358 if (ret)
359 goto out_unregister_blkdev;
360
361 for (i = 0; i < Z2MINOR_COUNT; i++) {
362 ret = z2ram_register_disk(minor: i);
363 if (ret && i == 0)
364 goto out_free_tagset;
365 }
366
367 return 0;
368
369out_free_tagset:
370 blk_mq_free_tag_set(set: &tag_set);
371out_unregister_blkdev:
372 unregister_blkdev(Z2RAM_MAJOR, DEVICE_NAME);
373 return ret;
374}
375
376static void __exit z2_exit(void)
377{
378 int i, j;
379
380 unregister_blkdev(Z2RAM_MAJOR, DEVICE_NAME);
381
382 for (i = 0; i < Z2MINOR_COUNT; i++) {
383 del_gendisk(gp: z2ram_gendisk[i]);
384 put_disk(disk: z2ram_gendisk[i]);
385 }
386 blk_mq_free_tag_set(set: &tag_set);
387
388 if (current_device != -1) {
389 i = 0;
390
391 for (j = 0; j < z2_count; j++) {
392 set_bit(nr: i++, addr: zorro_unused_z2ram);
393 }
394
395 for (j = 0; j < chip_count; j++) {
396 if (z2ram_map[i]) {
397 amiga_chip_free((void *)z2ram_map[i++]);
398 }
399 }
400
401 if (z2ram_map != NULL) {
402 kfree(objp: z2ram_map);
403 }
404 }
405
406 return;
407}
408
409module_init(z2_init);
410module_exit(z2_exit);
411MODULE_DESCRIPTION("Amiga Zorro II ramdisk driver");
412MODULE_LICENSE("GPL");
413

source code of linux/drivers/block/z2ram.c