1 /*
2  *	Functions to handle I2O memory
3  *
4  *	Pulled from the inlines in i2o headers and uninlined
5  *
6  *
7  *	This program is free software; you can redistribute it and/or modify it
8  *	under the terms of the GNU General Public License as published by the
9  *	Free Software Foundation; either version 2 of the License, or (at your
10  *	option) any later version.
11  */
12 
13 #include <linux/module.h>
14 #include <linux/i2o.h>
15 #include <linux/delay.h>
16 #include <linux/string.h>
17 #include <linux/slab.h>
18 #include "core.h"
19 
20 /* Protects our 32/64bit mask switching */
21 static DEFINE_MUTEX(mem_lock);
22 
23 /**
24  *	i2o_sg_tablesize - Calculate the maximum number of elements in a SGL
25  *	@c: I2O controller for which the calculation should be done
26  *	@body_size: maximum body size used for message in 32-bit words.
27  *
28  *	Return the maximum number of SG elements in a SG list.
29  */
i2o_sg_tablesize(struct i2o_controller * c,u16 body_size)30 u16 i2o_sg_tablesize(struct i2o_controller *c, u16 body_size)
31 {
32 	i2o_status_block *sb = c->status_block.virt;
33 	u16 sg_count =
34 	    (sb->inbound_frame_size - sizeof(struct i2o_message) / 4) -
35 	    body_size;
36 
37 	if (c->pae_support) {
38 		/*
39 		 * for 64-bit a SG attribute element must be added and each
40 		 * SG element needs 12 bytes instead of 8.
41 		 */
42 		sg_count -= 2;
43 		sg_count /= 3;
44 	} else
45 		sg_count /= 2;
46 
47 	if (c->short_req && (sg_count > 8))
48 		sg_count = 8;
49 
50 	return sg_count;
51 }
52 EXPORT_SYMBOL_GPL(i2o_sg_tablesize);
53 
54 
55 /**
56  *	i2o_dma_map_single - Map pointer to controller and fill in I2O message.
57  *	@c: I2O controller
58  *	@ptr: pointer to the data which should be mapped
59  *	@size: size of data in bytes
60  *	@direction: DMA_TO_DEVICE / DMA_FROM_DEVICE
61  *	@sg_ptr: pointer to the SG list inside the I2O message
62  *
63  *	This function does all necessary DMA handling and also writes the I2O
64  *	SGL elements into the I2O message. For details on DMA handling see also
65  *	dma_map_single(). The pointer sg_ptr will only be set to the end of the
66  *	SG list if the allocation was successful.
67  *
68  *	Returns DMA address which must be checked for failures using
69  *	dma_mapping_error().
70  */
i2o_dma_map_single(struct i2o_controller * c,void * ptr,size_t size,enum dma_data_direction direction,u32 ** sg_ptr)71 dma_addr_t i2o_dma_map_single(struct i2o_controller *c, void *ptr,
72 					    size_t size,
73 					    enum dma_data_direction direction,
74 					    u32 ** sg_ptr)
75 {
76 	u32 sg_flags;
77 	u32 *mptr = *sg_ptr;
78 	dma_addr_t dma_addr;
79 
80 	switch (direction) {
81 	case DMA_TO_DEVICE:
82 		sg_flags = 0xd4000000;
83 		break;
84 	case DMA_FROM_DEVICE:
85 		sg_flags = 0xd0000000;
86 		break;
87 	default:
88 		return 0;
89 	}
90 
91 	dma_addr = dma_map_single(&c->pdev->dev, ptr, size, direction);
92 	if (!dma_mapping_error(&c->pdev->dev, dma_addr)) {
93 #ifdef CONFIG_I2O_EXT_ADAPTEC_DMA64
94 		if ((sizeof(dma_addr_t) > 4) && c->pae_support) {
95 			*mptr++ = cpu_to_le32(0x7C020002);
96 			*mptr++ = cpu_to_le32(PAGE_SIZE);
97 		}
98 #endif
99 
100 		*mptr++ = cpu_to_le32(sg_flags | size);
101 		*mptr++ = cpu_to_le32(i2o_dma_low(dma_addr));
102 #ifdef CONFIG_I2O_EXT_ADAPTEC_DMA64
103 		if ((sizeof(dma_addr_t) > 4) && c->pae_support)
104 			*mptr++ = cpu_to_le32(i2o_dma_high(dma_addr));
105 #endif
106 		*sg_ptr = mptr;
107 	}
108 	return dma_addr;
109 }
110 EXPORT_SYMBOL_GPL(i2o_dma_map_single);
111 
112 /**
113  *	i2o_dma_map_sg - Map a SG List to controller and fill in I2O message.
114  *	@c: I2O controller
115  *	@sg: SG list to be mapped
116  *	@sg_count: number of elements in the SG list
117  *	@direction: DMA_TO_DEVICE / DMA_FROM_DEVICE
118  *	@sg_ptr: pointer to the SG list inside the I2O message
119  *
120  *	This function does all necessary DMA handling and also writes the I2O
121  *	SGL elements into the I2O message. For details on DMA handling see also
122  *	dma_map_sg(). The pointer sg_ptr will only be set to the end of the SG
123  *	list if the allocation was successful.
124  *
125  *	Returns 0 on failure or 1 on success.
126  */
i2o_dma_map_sg(struct i2o_controller * c,struct scatterlist * sg,int sg_count,enum dma_data_direction direction,u32 ** sg_ptr)127 int i2o_dma_map_sg(struct i2o_controller *c, struct scatterlist *sg,
128 	    int sg_count, enum dma_data_direction direction, u32 ** sg_ptr)
129 {
130 	u32 sg_flags;
131 	u32 *mptr = *sg_ptr;
132 
133 	switch (direction) {
134 	case DMA_TO_DEVICE:
135 		sg_flags = 0x14000000;
136 		break;
137 	case DMA_FROM_DEVICE:
138 		sg_flags = 0x10000000;
139 		break;
140 	default:
141 		return 0;
142 	}
143 
144 	sg_count = dma_map_sg(&c->pdev->dev, sg, sg_count, direction);
145 	if (!sg_count)
146 		return 0;
147 
148 #ifdef CONFIG_I2O_EXT_ADAPTEC_DMA64
149 	if ((sizeof(dma_addr_t) > 4) && c->pae_support) {
150 		*mptr++ = cpu_to_le32(0x7C020002);
151 		*mptr++ = cpu_to_le32(PAGE_SIZE);
152 	}
153 #endif
154 
155 	while (sg_count-- > 0) {
156 		if (!sg_count)
157 			sg_flags |= 0xC0000000;
158 		*mptr++ = cpu_to_le32(sg_flags | sg_dma_len(sg));
159 		*mptr++ = cpu_to_le32(i2o_dma_low(sg_dma_address(sg)));
160 #ifdef CONFIG_I2O_EXT_ADAPTEC_DMA64
161 		if ((sizeof(dma_addr_t) > 4) && c->pae_support)
162 			*mptr++ = cpu_to_le32(i2o_dma_high(sg_dma_address(sg)));
163 #endif
164 		sg = sg_next(sg);
165 	}
166 	*sg_ptr = mptr;
167 
168 	return 1;
169 }
170 EXPORT_SYMBOL_GPL(i2o_dma_map_sg);
171 
172 /**
173  *	i2o_dma_alloc - Allocate DMA memory
174  *	@dev: struct device pointer to the PCI device of the I2O controller
175  *	@addr: i2o_dma struct which should get the DMA buffer
176  *	@len: length of the new DMA memory
177  *
178  *	Allocate a coherent DMA memory and write the pointers into addr.
179  *
180  *	Returns 0 on success or -ENOMEM on failure.
181  */
i2o_dma_alloc(struct device * dev,struct i2o_dma * addr,size_t len)182 int i2o_dma_alloc(struct device *dev, struct i2o_dma *addr, size_t len)
183 {
184 	struct pci_dev *pdev = to_pci_dev(dev);
185 	int dma_64 = 0;
186 
187 	mutex_lock(&mem_lock);
188 	if ((sizeof(dma_addr_t) > 4) && (pdev->dma_mask == DMA_BIT_MASK(64))) {
189 		dma_64 = 1;
190 		if (pci_set_dma_mask(pdev, DMA_BIT_MASK(32))) {
191 			mutex_unlock(&mem_lock);
192 			return -ENOMEM;
193 		}
194 	}
195 
196 	addr->virt = dma_alloc_coherent(dev, len, &addr->phys, GFP_KERNEL);
197 
198 	if ((sizeof(dma_addr_t) > 4) && dma_64)
199 		if (pci_set_dma_mask(pdev, DMA_BIT_MASK(64)))
200 			printk(KERN_WARNING "i2o: unable to set 64-bit DMA");
201 	mutex_unlock(&mem_lock);
202 
203 	if (!addr->virt)
204 		return -ENOMEM;
205 
206 	memset(addr->virt, 0, len);
207 	addr->len = len;
208 
209 	return 0;
210 }
211 EXPORT_SYMBOL_GPL(i2o_dma_alloc);
212 
213 
214 /**
215  *	i2o_dma_free - Free DMA memory
216  *	@dev: struct device pointer to the PCI device of the I2O controller
217  *	@addr: i2o_dma struct which contains the DMA buffer
218  *
219  *	Free a coherent DMA memory and set virtual address of addr to NULL.
220  */
i2o_dma_free(struct device * dev,struct i2o_dma * addr)221 void i2o_dma_free(struct device *dev, struct i2o_dma *addr)
222 {
223 	if (addr->virt) {
224 		if (addr->phys)
225 			dma_free_coherent(dev, addr->len, addr->virt,
226 					  addr->phys);
227 		else
228 			kfree(addr->virt);
229 		addr->virt = NULL;
230 	}
231 }
232 EXPORT_SYMBOL_GPL(i2o_dma_free);
233 
234 
235 /**
236  *	i2o_dma_realloc - Realloc DMA memory
237  *	@dev: struct device pointer to the PCI device of the I2O controller
238  *	@addr: pointer to a i2o_dma struct DMA buffer
239  *	@len: new length of memory
240  *
241  *	If there was something allocated in the addr, free it first. If len > 0
242  *	than try to allocate it and write the addresses back to the addr
243  *	structure. If len == 0 set the virtual address to NULL.
244  *
245  *	Returns the 0 on success or negative error code on failure.
246  */
i2o_dma_realloc(struct device * dev,struct i2o_dma * addr,size_t len)247 int i2o_dma_realloc(struct device *dev, struct i2o_dma *addr, size_t len)
248 {
249 	i2o_dma_free(dev, addr);
250 
251 	if (len)
252 		return i2o_dma_alloc(dev, addr, len);
253 
254 	return 0;
255 }
256 EXPORT_SYMBOL_GPL(i2o_dma_realloc);
257 
258 /*
259  *	i2o_pool_alloc - Allocate an slab cache and mempool
260  *	@mempool: pointer to struct i2o_pool to write data into.
261  *	@name: name which is used to identify cache
262  *	@size: size of each object
263  *	@min_nr: minimum number of objects
264  *
265  *	First allocates a slab cache with name and size. Then allocates a
266  *	mempool which uses the slab cache for allocation and freeing.
267  *
268  *	Returns 0 on success or negative error code on failure.
269  */
i2o_pool_alloc(struct i2o_pool * pool,const char * name,size_t size,int min_nr)270 int i2o_pool_alloc(struct i2o_pool *pool, const char *name,
271 				 size_t size, int min_nr)
272 {
273 	pool->name = kmalloc(strlen(name) + 1, GFP_KERNEL);
274 	if (!pool->name)
275 		goto exit;
276 	strcpy(pool->name, name);
277 
278 	pool->slab =
279 	    kmem_cache_create(pool->name, size, 0, SLAB_HWCACHE_ALIGN, NULL);
280 	if (!pool->slab)
281 		goto free_name;
282 
283 	pool->mempool = mempool_create_slab_pool(min_nr, pool->slab);
284 	if (!pool->mempool)
285 		goto free_slab;
286 
287 	return 0;
288 
289 free_slab:
290 	kmem_cache_destroy(pool->slab);
291 
292 free_name:
293 	kfree(pool->name);
294 
295 exit:
296 	return -ENOMEM;
297 }
298 EXPORT_SYMBOL_GPL(i2o_pool_alloc);
299 
300 /*
301  *	i2o_pool_free - Free slab cache and mempool again
302  *	@mempool: pointer to struct i2o_pool which should be freed
303  *
304  *	Note that you have to return all objects to the mempool again before
305  *	calling i2o_pool_free().
306  */
i2o_pool_free(struct i2o_pool * pool)307 void i2o_pool_free(struct i2o_pool *pool)
308 {
309 	mempool_destroy(pool->mempool);
310 	kmem_cache_destroy(pool->slab);
311 	kfree(pool->name);
312 };
313 EXPORT_SYMBOL_GPL(i2o_pool_free);
314