drivers/scsi/cxgb3i/cxgb3i_ddp.h - maze/linux - Git at Google

 /*
  * cxgb3i_ddp.h: Chelsio S3xx iSCSI DDP Manager.
  *
  * Copyright (c) 2008 Chelsio Communications, Inc.
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
  * the Free Software Foundation.
  *
  * Written by: Karen Xie (kxie@chelsio.com)
  */

 #ifndef __CXGB3I_ULP2_DDP_H__
 #define __CXGB3I_ULP2_DDP_H__

 #include <linux/vmalloc.h>

 /**
  * struct cxgb3i_tag_format - cxgb3i ulp tag format for an iscsi entity
  *
  * @sw_bits:	# of bits used by iscsi software layer
  * @rsvd_bits:	# of bits used by h/w
  * @rsvd_shift:	h/w bits shift left
  * @rsvd_mask:	reserved bit mask
  */
 struct cxgb3i_tag_format {
 	unsigned char sw_bits;
 	unsigned char rsvd_bits;
 	unsigned char rsvd_shift;
 	unsigned char filler[1];
 	u32 rsvd_mask;
 };

 /**
  * struct cxgb3i_gather_list - cxgb3i direct data placement memory
  *
  * @tag:	ddp tag
  * @length:	total data buffer length
  * @offset:	initial offset to the 1st page
  * @nelem:	# of pages
  * @pages:	page pointers
  * @phys_addr:	physical address
  */
 struct cxgb3i_gather_list {
 	u32 tag;
 	unsigned int length;
 	unsigned int offset;
 	unsigned int nelem;
 	struct page **pages;
 	dma_addr_t phys_addr[0];
 };

 /**
  * struct cxgb3i_ddp_info - cxgb3i direct data placement for pdu payload
  *
  * @list:	list head to link elements
  * @refcnt:	ref. count
  * @tdev:	pointer to t3cdev used by cxgb3 driver
  * @max_txsz:	max tx packet size for ddp
  * @max_rxsz:	max rx packet size for ddp
  * @llimit:	lower bound of the page pod memory
  * @ulimit:	upper bound of the page pod memory
  * @nppods:	# of page pod entries
  * @idx_last:	page pod entry last used
  * @idx_bits:	# of bits the pagepod index would take
  * @idx_mask:	pagepod index mask
  * @rsvd_tag_mask: tag mask
  * @map_lock:	lock to synchonize access to the page pod map
  * @gl_map:	ddp memory gather list
  * @gl_skb:	skb used to program the pagepod
  */
 struct cxgb3i_ddp_info {
 	struct list_head list;
 	struct kref refcnt;
 	struct t3cdev *tdev;
 	struct pci_dev *pdev;
 	unsigned int max_txsz;
 	unsigned int max_rxsz;
 	unsigned int llimit;
 	unsigned int ulimit;
 	unsigned int nppods;
 	unsigned int idx_last;
 	unsigned char idx_bits;
 	unsigned char filler[3];
 	u32 idx_mask;
 	u32 rsvd_tag_mask;
 	spinlock_t map_lock;
 	struct cxgb3i_gather_list **gl_map;
 	struct sk_buff **gl_skb;
 };

 #define ISCSI_PDU_NONPAYLOAD_LEN	312 /* bhs(48) + ahs(256) + digest(8) */
 #define ULP2_MAX_PKT_SIZE	16224
 #define ULP2_MAX_PDU_PAYLOAD	(ULP2_MAX_PKT_SIZE - ISCSI_PDU_NONPAYLOAD_LEN)
 #define PPOD_PAGES_MAX		4
 #define PPOD_PAGES_SHIFT	2	/* 4 pages per pod */

 /*
  * struct pagepod_hdr, pagepod - pagepod format
  */
 struct pagepod_hdr {
 	u32 vld_tid;
 	u32 pgsz_tag_clr;
 	u32 maxoffset;
 	u32 pgoffset;
 	u64 rsvd;
 };

 struct pagepod {
 	struct pagepod_hdr hdr;
 	u64 addr[PPOD_PAGES_MAX + 1];
 };

 #define PPOD_SIZE		sizeof(struct pagepod)	/* 64 */
 #define PPOD_SIZE_SHIFT		6

 #define PPOD_COLOR_SHIFT	0
 #define PPOD_COLOR_SIZE		6
 #define PPOD_COLOR_MASK		((1 << PPOD_COLOR_SIZE) - 1)

 #define PPOD_IDX_SHIFT		PPOD_COLOR_SIZE
 #define PPOD_IDX_MAX_SIZE	24

 #define S_PPOD_TID    0
 #define M_PPOD_TID    0xFFFFFF
 #define V_PPOD_TID(x) ((x) << S_PPOD_TID)

 #define S_PPOD_VALID    24
 #define V_PPOD_VALID(x) ((x) << S_PPOD_VALID)
 #define F_PPOD_VALID    V_PPOD_VALID(1U)

 #define S_PPOD_COLOR    0
 #define M_PPOD_COLOR    0x3F
 #define V_PPOD_COLOR(x) ((x) << S_PPOD_COLOR)

 #define S_PPOD_TAG    6
 #define M_PPOD_TAG    0xFFFFFF
 #define V_PPOD_TAG(x) ((x) << S_PPOD_TAG)

 #define S_PPOD_PGSZ    30
 #define M_PPOD_PGSZ    0x3
 #define V_PPOD_PGSZ(x) ((x) << S_PPOD_PGSZ)

 /*
  * large memory chunk allocation/release
  * use vmalloc() if kmalloc() fails
  */
 static inline void *cxgb3i_alloc_big_mem(unsigned int size,
 					 gfp_t gfp)
 {
 	void *p = kmalloc(size, gfp);
 	if (!p)
 		p = vmalloc(size);
 	if (p)
 		memset(p, 0, size);
 	return p;
 }

 static inline void cxgb3i_free_big_mem(void *addr)
 {
 	if (is_vmalloc_addr(addr))
 		vfree(addr);
 	else
 		kfree(addr);
 }

 /*
  * cxgb3i ddp tag are 32 bits, it consists of reserved bits used by h/w and
  * non-reserved bits that can be used by the iscsi s/w.
  * The reserved bits are identified by the rsvd_bits and rsvd_shift fields
  * in struct cxgb3i_tag_format.
  *
  * The upper most reserved bit can be used to check if a tag is ddp tag or not:
  * 	if the bit is 0, the tag is a valid ddp tag
  */

 /**
  * cxgb3i_is_ddp_tag - check if a given tag is a hw/ddp tag
  * @tformat: tag format information
  * @tag: tag to be checked
  *
  * return true if the tag is a ddp tag, false otherwise.
  */
 static inline int cxgb3i_is_ddp_tag(struct cxgb3i_tag_format *tformat, u32 tag)
 {
 	return !(tag & (1 << (tformat->rsvd_bits + tformat->rsvd_shift - 1)));
 }

 /**
  * cxgb3i_sw_tag_usable - check if s/w tag has enough bits left for hw bits
  * @tformat: tag format information
  * @sw_tag: s/w tag to be checked
  *
  * return true if the tag can be used for hw ddp tag, false otherwise.
  */
 static inline int cxgb3i_sw_tag_usable(struct cxgb3i_tag_format *tformat,
 					u32 sw_tag)
 {
 	sw_tag >>= (32 - tformat->rsvd_bits);
 	return !sw_tag;
 }

 /**
  * cxgb3i_set_non_ddp_tag - mark a given s/w tag as an invalid ddp tag
  * @tformat: tag format information
  * @sw_tag: s/w tag to be checked
  *
  * insert 1 at the upper most reserved bit to mark it as an invalid ddp tag.
  */
 static inline u32 cxgb3i_set_non_ddp_tag(struct cxgb3i_tag_format *tformat,
 					 u32 sw_tag)
 {
 	unsigned char shift = tformat->rsvd_bits + tformat->rsvd_shift - 1;
 	u32 mask = (1 << shift) - 1;

 	if (sw_tag && (sw_tag & ~mask)) {
 		u32 v1 = sw_tag & ((1 << shift) - 1);
 		u32 v2 = (sw_tag >> (shift - 1)) << shift;

 		return v2 | v1 | 1 << shift;
 	}
 	return sw_tag | 1 << shift;
 }

 /**
  * cxgb3i_ddp_tag_base - shift s/w tag bits so that reserved bits are not used
  * @tformat: tag format information
  * @sw_tag: s/w tag to be checked
  */
 static inline u32 cxgb3i_ddp_tag_base(struct cxgb3i_tag_format *tformat,
 				      u32 sw_tag)
 {
 	u32 mask = (1 << tformat->rsvd_shift) - 1;

 	if (sw_tag && (sw_tag & ~mask)) {
 		u32 v1 = sw_tag & mask;
 		u32 v2 = sw_tag >> tformat->rsvd_shift;

 		v2 <<= tformat->rsvd_shift + tformat->rsvd_bits;
 		return v2 | v1;
 	}
 	return sw_tag;
 }

 /**
  * cxgb3i_tag_rsvd_bits - get the reserved bits used by the h/w
  * @tformat: tag format information
  * @tag: tag to be checked
  *
  * return the reserved bits in the tag
  */
 static inline u32 cxgb3i_tag_rsvd_bits(struct cxgb3i_tag_format *tformat,
 				       u32 tag)
 {
 	if (cxgb3i_is_ddp_tag(tformat, tag))
 		return (tag >> tformat->rsvd_shift) & tformat->rsvd_mask;
 	return 0;
 }

 /**
  * cxgb3i_tag_nonrsvd_bits - get the non-reserved bits used by the s/w
  * @tformat: tag format information
  * @tag: tag to be checked
  *
  * return the non-reserved bits in the tag.
  */
 static inline u32 cxgb3i_tag_nonrsvd_bits(struct cxgb3i_tag_format *tformat,
 					  u32 tag)
 {
 	unsigned char shift = tformat->rsvd_bits + tformat->rsvd_shift - 1;
 	u32 v1, v2;

 	if (cxgb3i_is_ddp_tag(tformat, tag)) {
 		v1 = tag & ((1 << tformat->rsvd_shift) - 1);
 		v2 = (tag >> (shift + 1)) << tformat->rsvd_shift;
 	} else {
 		u32 mask = (1 << shift) - 1;

 		tag &= ~(1 << shift);
 		v1 = tag & mask;
 		v2 = (tag >> 1) & ~mask;
 	}
 	return v1 | v2;
 }

 int cxgb3i_ddp_tag_reserve(struct t3cdev *, unsigned int tid,
 			   struct cxgb3i_tag_format *, u32 *tag,
 			   struct cxgb3i_gather_list *, gfp_t gfp);
 void cxgb3i_ddp_tag_release(struct t3cdev *, u32 tag);

 struct cxgb3i_gather_list *cxgb3i_ddp_make_gl(unsigned int xferlen,
 				struct scatterlist *sgl,
 				unsigned int sgcnt,
 				struct pci_dev *pdev,
 				gfp_t gfp);
 void cxgb3i_ddp_release_gl(struct cxgb3i_gather_list *gl,
 				struct pci_dev *pdev);

 int cxgb3i_setup_conn_host_pagesize(struct t3cdev *, unsigned int tid,
 				    int reply);
 int cxgb3i_setup_conn_pagesize(struct t3cdev *, unsigned int tid, int reply,
 			       unsigned long pgsz);
 int cxgb3i_setup_conn_digest(struct t3cdev *, unsigned int tid,
 				int hcrc, int dcrc, int reply);
 int cxgb3i_ddp_find_page_index(unsigned long pgsz);
 int cxgb3i_adapter_ddp_info(struct t3cdev *, struct cxgb3i_tag_format *,
 			    unsigned int *txsz, unsigned int *rxsz);

 void cxgb3i_ddp_init(struct t3cdev *);
 void cxgb3i_ddp_cleanup(struct t3cdev *);
 #endif
	/*
	* cxgb3i_ddp.h: Chelsio S3xx iSCSI DDP Manager.
	*
	* Copyright (c) 2008 Chelsio Communications, Inc.
	*
	* This program is free software; you can redistribute it and/or modify
	* it under the terms of the GNU General Public License as published by
	* the Free Software Foundation.
	*
	* Written by: Karen Xie (kxie@chelsio.com)
	*/

	#ifndef __CXGB3I_ULP2_DDP_H__
	#define __CXGB3I_ULP2_DDP_H__

	#include <linux/vmalloc.h>

	/**
	* struct cxgb3i_tag_format - cxgb3i ulp tag format for an iscsi entity
	*
	* @sw_bits: # of bits used by iscsi software layer
	* @rsvd_bits: # of bits used by h/w
	* @rsvd_shift: h/w bits shift left
	* @rsvd_mask: reserved bit mask
	*/
	struct cxgb3i_tag_format {
	unsigned char sw_bits;
	unsigned char rsvd_bits;
	unsigned char rsvd_shift;
	unsigned char filler[1];
	u32 rsvd_mask;
	};

	/**
	* struct cxgb3i_gather_list - cxgb3i direct data placement memory
	*
	* @tag: ddp tag
	* @length: total data buffer length
	* @offset: initial offset to the 1st page
	* @nelem: # of pages
	* @pages: page pointers
	* @phys_addr: physical address
	*/
	struct cxgb3i_gather_list {
	u32 tag;
	unsigned int length;
	unsigned int offset;
	unsigned int nelem;
	struct page **pages;
	dma_addr_t phys_addr[0];
	};

	/**
	* struct cxgb3i_ddp_info - cxgb3i direct data placement for pdu payload
	*
	* @list: list head to link elements
	* @refcnt: ref. count
	* @tdev: pointer to t3cdev used by cxgb3 driver
	* @max_txsz: max tx packet size for ddp
	* @max_rxsz: max rx packet size for ddp
	* @llimit: lower bound of the page pod memory
	* @ulimit: upper bound of the page pod memory
	* @nppods: # of page pod entries
	* @idx_last: page pod entry last used
	* @idx_bits: # of bits the pagepod index would take
	* @idx_mask: pagepod index mask
	* @rsvd_tag_mask: tag mask
	* @map_lock: lock to synchonize access to the page pod map
	* @gl_map: ddp memory gather list
	* @gl_skb: skb used to program the pagepod
	*/
	struct cxgb3i_ddp_info {
	struct list_head list;
	struct kref refcnt;
	struct t3cdev *tdev;
	struct pci_dev *pdev;
	unsigned int max_txsz;
	unsigned int max_rxsz;
	unsigned int llimit;
	unsigned int ulimit;
	unsigned int nppods;
	unsigned int idx_last;
	unsigned char idx_bits;
	unsigned char filler[3];
	u32 idx_mask;
	u32 rsvd_tag_mask;
	spinlock_t map_lock;
	struct cxgb3i_gather_list **gl_map;
	struct sk_buff **gl_skb;
	};

	#define ISCSI_PDU_NONPAYLOAD_LEN 312 /* bhs(48) + ahs(256) + digest(8) */
	#define ULP2_MAX_PKT_SIZE 16224
	#define ULP2_MAX_PDU_PAYLOAD (ULP2_MAX_PKT_SIZE - ISCSI_PDU_NONPAYLOAD_LEN)
	#define PPOD_PAGES_MAX 4
	#define PPOD_PAGES_SHIFT 2 /* 4 pages per pod */

	/*
	* struct pagepod_hdr, pagepod - pagepod format
	*/
	struct pagepod_hdr {
	u32 vld_tid;
	u32 pgsz_tag_clr;
	u32 maxoffset;
	u32 pgoffset;
	u64 rsvd;
	};

	struct pagepod {
	struct pagepod_hdr hdr;
	u64 addr[PPOD_PAGES_MAX + 1];
	};

	#define PPOD_SIZE sizeof(struct pagepod) /* 64 */
	#define PPOD_SIZE_SHIFT 6

	#define PPOD_COLOR_SHIFT 0
	#define PPOD_COLOR_SIZE 6
	#define PPOD_COLOR_MASK ((1 << PPOD_COLOR_SIZE) - 1)

	#define PPOD_IDX_SHIFT PPOD_COLOR_SIZE
	#define PPOD_IDX_MAX_SIZE 24

	#define S_PPOD_TID 0
	#define M_PPOD_TID 0xFFFFFF
	#define V_PPOD_TID(x) ((x) << S_PPOD_TID)

	#define S_PPOD_VALID 24
	#define V_PPOD_VALID(x) ((x) << S_PPOD_VALID)
	#define F_PPOD_VALID V_PPOD_VALID(1U)

	#define S_PPOD_COLOR 0
	#define M_PPOD_COLOR 0x3F
	#define V_PPOD_COLOR(x) ((x) << S_PPOD_COLOR)

	#define S_PPOD_TAG 6
	#define M_PPOD_TAG 0xFFFFFF
	#define V_PPOD_TAG(x) ((x) << S_PPOD_TAG)

	#define S_PPOD_PGSZ 30
	#define M_PPOD_PGSZ 0x3
	#define V_PPOD_PGSZ(x) ((x) << S_PPOD_PGSZ)

	/*
	* large memory chunk allocation/release
	* use vmalloc() if kmalloc() fails
	*/
	static inline void *cxgb3i_alloc_big_mem(unsigned int size,
	gfp_t gfp)
	{
	void *p = kmalloc(size, gfp);
	if (!p)
	p = vmalloc(size);
	if (p)
	memset(p, 0, size);
	return p;
	}

	static inline void cxgb3i_free_big_mem(void *addr)
	{
	if (is_vmalloc_addr(addr))
	vfree(addr);
	else
	kfree(addr);
	}

	/*
	* cxgb3i ddp tag are 32 bits, it consists of reserved bits used by h/w and
	* non-reserved bits that can be used by the iscsi s/w.
	* The reserved bits are identified by the rsvd_bits and rsvd_shift fields
	* in struct cxgb3i_tag_format.
	*
	* The upper most reserved bit can be used to check if a tag is ddp tag or not:
	* if the bit is 0, the tag is a valid ddp tag
	*/

	/**
	* cxgb3i_is_ddp_tag - check if a given tag is a hw/ddp tag
	* @tformat: tag format information
	* @tag: tag to be checked
	*
	* return true if the tag is a ddp tag, false otherwise.
	*/
	static inline int cxgb3i_is_ddp_tag(struct cxgb3i_tag_format *tformat, u32 tag)
	{
	return !(tag & (1 << (tformat->rsvd_bits + tformat->rsvd_shift - 1)));
	}

	/**
	* cxgb3i_sw_tag_usable - check if s/w tag has enough bits left for hw bits
	* @tformat: tag format information
	* @sw_tag: s/w tag to be checked
	*
	* return true if the tag can be used for hw ddp tag, false otherwise.
	*/
	static inline int cxgb3i_sw_tag_usable(struct cxgb3i_tag_format *tformat,
	u32 sw_tag)
	{
	sw_tag >>= (32 - tformat->rsvd_bits);
	return !sw_tag;
	}

	/**
	* cxgb3i_set_non_ddp_tag - mark a given s/w tag as an invalid ddp tag
	* @tformat: tag format information
	* @sw_tag: s/w tag to be checked
	*
	* insert 1 at the upper most reserved bit to mark it as an invalid ddp tag.
	*/
	static inline u32 cxgb3i_set_non_ddp_tag(struct cxgb3i_tag_format *tformat,
	u32 sw_tag)
	{
	unsigned char shift = tformat->rsvd_bits + tformat->rsvd_shift - 1;
	u32 mask = (1 << shift) - 1;

	if (sw_tag && (sw_tag & ~mask)) {
	u32 v1 = sw_tag & ((1 << shift) - 1);
	u32 v2 = (sw_tag >> (shift - 1)) << shift;

	return v2 \| v1 \| 1 << shift;
	}
	return sw_tag \| 1 << shift;
	}

	/**
	* cxgb3i_ddp_tag_base - shift s/w tag bits so that reserved bits are not used
	* @tformat: tag format information
	* @sw_tag: s/w tag to be checked
	*/
	static inline u32 cxgb3i_ddp_tag_base(struct cxgb3i_tag_format *tformat,
	u32 sw_tag)
	{
	u32 mask = (1 << tformat->rsvd_shift) - 1;

	if (sw_tag && (sw_tag & ~mask)) {
	u32 v1 = sw_tag & mask;
	u32 v2 = sw_tag >> tformat->rsvd_shift;

	v2 <<= tformat->rsvd_shift + tformat->rsvd_bits;
	return v2 \| v1;
	}
	return sw_tag;
	}

	/**
	* cxgb3i_tag_rsvd_bits - get the reserved bits used by the h/w
	* @tformat: tag format information
	* @tag: tag to be checked
	*
	* return the reserved bits in the tag
	*/
	static inline u32 cxgb3i_tag_rsvd_bits(struct cxgb3i_tag_format *tformat,
	u32 tag)
	{
	if (cxgb3i_is_ddp_tag(tformat, tag))
	return (tag >> tformat->rsvd_shift) & tformat->rsvd_mask;
	return 0;
	}

	/**
	* cxgb3i_tag_nonrsvd_bits - get the non-reserved bits used by the s/w
	* @tformat: tag format information
	* @tag: tag to be checked
	*
	* return the non-reserved bits in the tag.
	*/
	static inline u32 cxgb3i_tag_nonrsvd_bits(struct cxgb3i_tag_format *tformat,
	u32 tag)
	{
	unsigned char shift = tformat->rsvd_bits + tformat->rsvd_shift - 1;
	u32 v1, v2;

	if (cxgb3i_is_ddp_tag(tformat, tag)) {
	v1 = tag & ((1 << tformat->rsvd_shift) - 1);
	v2 = (tag >> (shift + 1)) << tformat->rsvd_shift;
	} else {
	u32 mask = (1 << shift) - 1;

	tag &= ~(1 << shift);
	v1 = tag & mask;
	v2 = (tag >> 1) & ~mask;
	}
	return v1 \| v2;
	}

	int cxgb3i_ddp_tag_reserve(struct t3cdev *, unsigned int tid,
	struct cxgb3i_tag_format , u32 tag,
	struct cxgb3i_gather_list *, gfp_t gfp);
	void cxgb3i_ddp_tag_release(struct t3cdev *, u32 tag);

	struct cxgb3i_gather_list *cxgb3i_ddp_make_gl(unsigned int xferlen,
	struct scatterlist *sgl,
	unsigned int sgcnt,
	struct pci_dev *pdev,
	gfp_t gfp);
	void cxgb3i_ddp_release_gl(struct cxgb3i_gather_list *gl,
	struct pci_dev *pdev);

	int cxgb3i_setup_conn_host_pagesize(struct t3cdev *, unsigned int tid,
	int reply);
	int cxgb3i_setup_conn_pagesize(struct t3cdev *, unsigned int tid, int reply,
	unsigned long pgsz);
	int cxgb3i_setup_conn_digest(struct t3cdev *, unsigned int tid,
	int hcrc, int dcrc, int reply);
	int cxgb3i_ddp_find_page_index(unsigned long pgsz);
	int cxgb3i_adapter_ddp_info(struct t3cdev , struct cxgb3i_tag_format ,
	unsigned int txsz, unsigned int rxsz);

	void cxgb3i_ddp_init(struct t3cdev *);
	void cxgb3i_ddp_cleanup(struct t3cdev *);
	#endif