[linux-block.git] / arch / s390 / include / asm / idals.h

/* 
 * Author(s)......: Holger Smolinski <Holger.Smolinski@de.ibm.com>
 *		    Martin Schwidefsky <schwidefsky@de.ibm.com>
 * Bugreports.to..: <Linux390@de.ibm.com>
 * Copyright IBM Corp. 2000
 *
 * History of changes
 * 07/24/00 new file
 * 05/04/02 code restructuring.
 */

#ifndef _S390_IDALS_H
#define _S390_IDALS_H

#include <linux/errno.h>
#include <linux/err.h>
#include <linux/types.h>
#include <linux/slab.h>
#include <asm/cio.h>
#include <linux/uaccess.h>

#define IDA_SIZE_LOG 12 /* 11 for 2k , 12 for 4k */
#define IDA_BLOCK_SIZE (1L<<IDA_SIZE_LOG)

/*
 * Test if an address/length pair needs an idal list.
 */
static inline int
idal_is_needed(void *vaddr, unsigned int length)
{
	return ((__pa(vaddr) + length - 1) >> 31) != 0;
}


/*
 * Return the number of idal words needed for an address/length pair.
 */
static inline unsigned int idal_nr_words(void *vaddr, unsigned int length)
{
	return ((__pa(vaddr) & (IDA_BLOCK_SIZE-1)) + length +
		(IDA_BLOCK_SIZE-1)) >> IDA_SIZE_LOG;
}

/*
 * Create the list of idal words for an address/length pair.
 */
static inline unsigned long *idal_create_words(unsigned long *idaws,
					       void *vaddr, unsigned int length)
{
	unsigned long paddr;
	unsigned int cidaw;

	paddr = __pa(vaddr);
	cidaw = ((paddr & (IDA_BLOCK_SIZE-1)) + length + 
		 (IDA_BLOCK_SIZE-1)) >> IDA_SIZE_LOG;
	*idaws++ = paddr;
	paddr &= -IDA_BLOCK_SIZE;
	while (--cidaw > 0) {
		paddr += IDA_BLOCK_SIZE;
		*idaws++ = paddr;
	}
	return idaws;
}

/*
 * Sets the address of the data in CCW.
 * If necessary it allocates an IDAL and sets the appropriate flags.
 */
static inline int
set_normalized_cda(struct ccw1 * ccw, void *vaddr)
{
	unsigned int nridaws;
	unsigned long *idal;

	if (ccw->flags & CCW_FLAG_IDA)
		return -EINVAL;
	nridaws = idal_nr_words(vaddr, ccw->count);
	if (nridaws > 0) {
		idal = kmalloc(nridaws * sizeof(unsigned long),
			       GFP_ATOMIC | GFP_DMA );
		if (idal == NULL)
			return -ENOMEM;
		idal_create_words(idal, vaddr, ccw->count);
		ccw->flags |= CCW_FLAG_IDA;
		vaddr = idal;
	}
	ccw->cda = (__u32)(unsigned long) vaddr;
	return 0;
}

/*
 * Releases any allocated IDAL related to the CCW.
 */
static inline void
clear_normalized_cda(struct ccw1 * ccw)
{
	if (ccw->flags & CCW_FLAG_IDA) {
		kfree((void *)(unsigned long) ccw->cda);
		ccw->flags &= ~CCW_FLAG_IDA;
	}
	ccw->cda = 0;
}

/*
 * Idal buffer extension
 */
struct idal_buffer {
	size_t size;
	size_t page_order;
	void *data[0];
};

/*
 * Allocate an idal buffer
 */
static inline struct idal_buffer *
idal_buffer_alloc(size_t size, int page_order)
{
	struct idal_buffer *ib;
	int nr_chunks, nr_ptrs, i;

	nr_ptrs = (size + IDA_BLOCK_SIZE - 1) >> IDA_SIZE_LOG;
	nr_chunks = (4096 << page_order) >> IDA_SIZE_LOG;
	ib = kmalloc(sizeof(struct idal_buffer) + nr_ptrs*sizeof(void *),
		     GFP_DMA | GFP_KERNEL);
	if (ib == NULL)
		return ERR_PTR(-ENOMEM);
	ib->size = size;
	ib->page_order = page_order;
	for (i = 0; i < nr_ptrs; i++) {
		if ((i & (nr_chunks - 1)) != 0) {
			ib->data[i] = ib->data[i-1] + IDA_BLOCK_SIZE;
			continue;
		}
		ib->data[i] = (void *)
			__get_free_pages(GFP_KERNEL, page_order);
		if (ib->data[i] != NULL)
			continue;
		// Not enough memory
		while (i >= nr_chunks) {
			i -= nr_chunks;
			free_pages((unsigned long) ib->data[i],
				   ib->page_order);
		}
		kfree(ib);
		return ERR_PTR(-ENOMEM);
	}
	return ib;
}

/*
 * Free an idal buffer.
 */
static inline void
idal_buffer_free(struct idal_buffer *ib)
{
	int nr_chunks, nr_ptrs, i;

	nr_ptrs = (ib->size + IDA_BLOCK_SIZE - 1) >> IDA_SIZE_LOG;
	nr_chunks = (4096 << ib->page_order) >> IDA_SIZE_LOG;
	for (i = 0; i < nr_ptrs; i += nr_chunks)
		free_pages((unsigned long) ib->data[i], ib->page_order);
	kfree(ib);
}

/*
 * Test if a idal list is really needed.
 */
static inline int
__idal_buffer_is_needed(struct idal_buffer *ib)
{
	return ib->size > (4096ul << ib->page_order) ||
		idal_is_needed(ib->data[0], ib->size);
}

/*
 * Set channel data address to idal buffer.
 */
static inline void
idal_buffer_set_cda(struct idal_buffer *ib, struct ccw1 *ccw)
{
	if (__idal_buffer_is_needed(ib)) {
		// setup idals;
		ccw->cda = (u32)(addr_t) ib->data;
		ccw->flags |= CCW_FLAG_IDA;
	} else
		// we do not need idals - use direct addressing
		ccw->cda = (u32)(addr_t) ib->data[0];
	ccw->count = ib->size;
}

/*
 * Copy count bytes from an idal buffer to user memory
 */
static inline size_t
idal_buffer_to_user(struct idal_buffer *ib, void __user *to, size_t count)
{
	size_t left;
	int i;

	BUG_ON(count > ib->size);
	for (i = 0; count > IDA_BLOCK_SIZE; i++) {
		left = copy_to_user(to, ib->data[i], IDA_BLOCK_SIZE);
		if (left)
			return left + count - IDA_BLOCK_SIZE;
		to = (void __user *) to + IDA_BLOCK_SIZE;
		count -= IDA_BLOCK_SIZE;
	}
	return copy_to_user(to, ib->data[i], count);
}

/*
 * Copy count bytes from user memory to an idal buffer
 */
static inline size_t
idal_buffer_from_user(struct idal_buffer *ib, const void __user *from, size_t count)
{
	size_t left;
	int i;

	BUG_ON(count > ib->size);
	for (i = 0; count > IDA_BLOCK_SIZE; i++) {
		left = copy_from_user(ib->data[i], from, IDA_BLOCK_SIZE);
		if (left)
			return left + count - IDA_BLOCK_SIZE;
		from = (void __user *) from + IDA_BLOCK_SIZE;
		count -= IDA_BLOCK_SIZE;
	}
	return copy_from_user(ib->data[i], from, count);
}

#endif
Commit	Line	Data
1da177e4	1	/*
1da177e4 LT	2	* Author(s)......: Holger Smolinski <Holger.Smolinski@de.ibm.com>
	3	* Martin Schwidefsky <schwidefsky@de.ibm.com>
	4	* Bugreports.to..: <Linux390@de.ibm.com>
a53c8fab HC	5	* Copyright IBM Corp. 2000
a53c8fab HC	6	*
1da177e4 LT	7	* History of changes
	8	* 07/24/00 new file
	9	* 05/04/02 code restructuring.
	10	*/
	11
	12	#ifndef _S390_IDALS_H
	13	#define _S390_IDALS_H
	14
1da177e4 LT	15	#include <linux/errno.h>
	16	#include <linux/err.h>
	17	#include <linux/types.h>
	18	#include <linux/slab.h>
	19	#include <asm/cio.h>
7c0f6ba6	20	#include <linux/uaccess.h>
1da177e4	21
1da177e4	22	#define IDA_SIZE_LOG 12 /* 11 for 2k , 12 for 4k */
1da177e4 LT	23	#define IDA_BLOCK_SIZE (1L<<IDA_SIZE_LOG)
	24
	25	/*
	26	* Test if an address/length pair needs an idal list.
	27	*/
	28	static inline int
	29	idal_is_needed(void *vaddr, unsigned int length)
	30	{
1da177e4	31	return ((__pa(vaddr) + length - 1) >> 31) != 0;
1da177e4 LT	32	}
	33
	34
	35	/*
	36	* Return the number of idal words needed for an address/length pair.
	37	*/
f3eb5384	38	static inline unsigned int idal_nr_words(void *vaddr, unsigned int length)
1da177e4	39	{
f3eb5384 SW	40	return ((__pa(vaddr) & (IDA_BLOCK_SIZE-1)) + length +
f3eb5384 SW	41	(IDA_BLOCK_SIZE-1)) >> IDA_SIZE_LOG;
1da177e4 LT	42	}
	43
	44	/*
	45	* Create the list of idal words for an address/length pair.
	46	*/
f3eb5384 SW	47	static inline unsigned long idal_create_words(unsigned long idaws,
f3eb5384 SW	48	void *vaddr, unsigned int length)
1da177e4	49	{
1da177e4 LT	50	unsigned long paddr;
	51	unsigned int cidaw;
	52
	53	paddr = __pa(vaddr);
	54	cidaw = ((paddr & (IDA_BLOCK_SIZE-1)) + length +
	55	(IDA_BLOCK_SIZE-1)) >> IDA_SIZE_LOG;
	56	*idaws++ = paddr;
	57	paddr &= -IDA_BLOCK_SIZE;
	58	while (--cidaw > 0) {
	59	paddr += IDA_BLOCK_SIZE;
	60	*idaws++ = paddr;
	61	}
1da177e4 LT	62	return idaws;
	63	}
	64
	65	/*
	66	* Sets the address of the data in CCW.
	67	* If necessary it allocates an IDAL and sets the appropriate flags.
	68	*/
	69	static inline int
	70	set_normalized_cda(struct ccw1 * ccw, void *vaddr)
	71	{
1da177e4 LT	72	unsigned int nridaws;
	73	unsigned long *idal;
	74
	75	if (ccw->flags & CCW_FLAG_IDA)
	76	return -EINVAL;
	77	nridaws = idal_nr_words(vaddr, ccw->count);
	78	if (nridaws > 0) {
	79	idal = kmalloc(nridaws * sizeof(unsigned long),
	80	GFP_ATOMIC \| GFP_DMA );
	81	if (idal == NULL)
	82	return -ENOMEM;
	83	idal_create_words(idal, vaddr, ccw->count);
	84	ccw->flags \|= CCW_FLAG_IDA;
	85	vaddr = idal;
	86	}
1da177e4 LT	87	ccw->cda = (__u32)(unsigned long) vaddr;
	88	return 0;
	89	}
	90
	91	/*
	92	* Releases any allocated IDAL related to the CCW.
	93	*/
	94	static inline void
	95	clear_normalized_cda(struct ccw1 * ccw)
	96	{
1da177e4 LT	97	if (ccw->flags & CCW_FLAG_IDA) {
	98	kfree((void *)(unsigned long) ccw->cda);
	99	ccw->flags &= ~CCW_FLAG_IDA;
	100	}
1da177e4 LT	101	ccw->cda = 0;
	102	}
	103
	104	/*
	105	* Idal buffer extension
	106	*/
	107	struct idal_buffer {
	108	size_t size;
	109	size_t page_order;
	110	void *data[0];
	111	};
	112
	113	/*
	114	* Allocate an idal buffer
	115	*/
	116	static inline struct idal_buffer *
	117	idal_buffer_alloc(size_t size, int page_order)
	118	{
	119	struct idal_buffer *ib;
	120	int nr_chunks, nr_ptrs, i;
	121
	122	nr_ptrs = (size + IDA_BLOCK_SIZE - 1) >> IDA_SIZE_LOG;
	123	nr_chunks = (4096 << page_order) >> IDA_SIZE_LOG;
	124	ib = kmalloc(sizeof(struct idal_buffer) + nr_ptrssizeof(void ),
	125	GFP_DMA \| GFP_KERNEL);
	126	if (ib == NULL)
	127	return ERR_PTR(-ENOMEM);
	128	ib->size = size;
	129	ib->page_order = page_order;
	130	for (i = 0; i < nr_ptrs; i++) {
	131	if ((i & (nr_chunks - 1)) != 0) {
	132	ib->data[i] = ib->data[i-1] + IDA_BLOCK_SIZE;
	133	continue;
	134	}
	135	ib->data[i] = (void *)
	136	__get_free_pages(GFP_KERNEL, page_order);
	137	if (ib->data[i] != NULL)
	138	continue;
	139	// Not enough memory
	140	while (i >= nr_chunks) {
	141	i -= nr_chunks;
	142	free_pages((unsigned long) ib->data[i],
	143	ib->page_order);
	144	}
	145	kfree(ib);
	146	return ERR_PTR(-ENOMEM);
	147	}
	148	return ib;
	149	}
	150
	151	/*
	152	* Free an idal buffer.
	153	*/
	154	static inline void
	155	idal_buffer_free(struct idal_buffer *ib)
	156	{
	157	int nr_chunks, nr_ptrs, i;
	158
	159	nr_ptrs = (ib->size + IDA_BLOCK_SIZE - 1) >> IDA_SIZE_LOG;
	160	nr_chunks = (4096 << ib->page_order) >> IDA_SIZE_LOG;
	161	for (i = 0; i < nr_ptrs; i += nr_chunks)
	162	free_pages((unsigned long) ib->data[i], ib->page_order);
	163	kfree(ib);
	164	}
165
166	/*
167	* Test if a idal list is really needed.
168	*/
169	static inline int
170	__idal_buffer_is_needed(struct idal_buffer *ib)
171	{
1da177e4 LT	172	return ib->size > (4096ul << ib->page_order) \|\|
1da177e4 LT	173	idal_is_needed(ib->data[0], ib->size);
1da177e4 LT	174	}
	175
	176	/*
	177	* Set channel data address to idal buffer.
	178	*/
	179	static inline void
	180	idal_buffer_set_cda(struct idal_buffer ib, struct ccw1 ccw)
	181	{
	182	if (__idal_buffer_is_needed(ib)) {
	183	// setup idals;
	184	ccw->cda = (u32)(addr_t) ib->data;
	185	ccw->flags \|= CCW_FLAG_IDA;
	186	} else
	187	// we do not need idals - use direct addressing
	188	ccw->cda = (u32)(addr_t) ib->data[0];
	189	ccw->count = ib->size;
	190	}
	191
	192	/*
	193	* Copy count bytes from an idal buffer to user memory
	194	*/
	195	static inline size_t
	196	idal_buffer_to_user(struct idal_buffer ib, void __user to, size_t count)
	197	{
	198	size_t left;
	199	int i;
	200
	201	BUG_ON(count > ib->size);
	202	for (i = 0; count > IDA_BLOCK_SIZE; i++) {
	203	left = copy_to_user(to, ib->data[i], IDA_BLOCK_SIZE);
	204	if (left)
	205	return left + count - IDA_BLOCK_SIZE;
	206	to = (void __user *) to + IDA_BLOCK_SIZE;
	207	count -= IDA_BLOCK_SIZE;
	208	}
	209	return copy_to_user(to, ib->data[i], count);
	210	}
	211
	212	/*
	213	* Copy count bytes from user memory to an idal buffer
	214	*/
	215	static inline size_t
	216	idal_buffer_from_user(struct idal_buffer ib, const void __user from, size_t count)
	217	{
	218	size_t left;
	219	int i;
	220
	221	BUG_ON(count > ib->size);
	222	for (i = 0; count > IDA_BLOCK_SIZE; i++) {
	223	left = copy_from_user(ib->data[i], from, IDA_BLOCK_SIZE);
	224	if (left)
	225	return left + count - IDA_BLOCK_SIZE;
	226	from = (void __user *) from + IDA_BLOCK_SIZE;
	227	count -= IDA_BLOCK_SIZE;
	228	}
	229	return copy_from_user(ib->data[i], from, count);
	230	}
	231
	232	#endif