drivers/scsi/cxgb3i/cxgb3i_ddp.h

   1 /*
   2  * cxgb3i_ddp.h: Chelsio S3xx iSCSI DDP Manager.
   3  *
   4  * Copyright (c) 2008 Chelsio Communications, Inc.
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation.
   9  *
  10  * Written by: Karen Xie (kxie@chelsio.com)
  11  */
  12
  13 #ifndef __CXGB3I_ULP2_DDP_H__
  14 #define __CXGB3I_ULP2_DDP_H__
  15
  16 /**
  17  * struct cxgb3i_tag_format - cxgb3i ulp tag format for an iscsi entity
  18  *
  19  * @sw_bits:    # of bits used by iscsi software layer
  20  * @rsvd_bits:  # of bits used by h/w
  21  * @rsvd_shift: h/w bits shift left
  22  * @rsvd_mask:  reserved bit mask
  23  */
  24 struct cxgb3i_tag_format {
  25         unsigned char sw_bits;
  26         unsigned char rsvd_bits;
  27         unsigned char rsvd_shift;
  28         unsigned char filler[1];
  29         u32 rsvd_mask;
  30 };
  31
  32 /**
  33  * struct cxgb3i_gather_list - cxgb3i direct data placement memory
  34  *
  35  * @tag:        ddp tag
  36  * @length:     total data buffer length
  37  * @offset:     initial offset to the 1st page
  38  * @nelem:      # of pages
  39  * @pages:      page pointers
  40  * @phys_addr:  physical address
  41  */
  42 struct cxgb3i_gather_list {
  43         u32 tag;
  44         unsigned int length;
  45         unsigned int offset;
  46         unsigned int nelem;
  47         struct page **pages;
  48         dma_addr_t phys_addr[0];
  49 };
  50
  51 /**
  52  * struct cxgb3i_ddp_info - cxgb3i direct data placement for pdu payload
  53  *
  54  * @list:       list head to link elements
  55  * @tdev:       pointer to t3cdev used by cxgb3 driver
  56  * @max_txsz:   max tx packet size for ddp
  57  * @max_rxsz:   max rx packet size for ddp
  58  * @llimit:     lower bound of the page pod memory
  59  * @ulimit:     upper bound of the page pod memory
  60  * @nppods:     # of page pod entries
  61  * @idx_last:   page pod entry last used
  62  * @idx_bits:   # of bits the pagepod index would take
  63  * @idx_mask:   pagepod index mask
  64  * @rsvd_tag_mask: tag mask
  65  * @map_lock:   lock to synchonize access to the page pod map
  66  * @gl_map:     ddp memory gather list
  67  * @gl_skb:     skb used to program the pagepod
  68  */
  69 struct cxgb3i_ddp_info {
  70         struct list_head list;
  71         struct t3cdev *tdev;
  72         struct pci_dev *pdev;
  73         unsigned int max_txsz;
  74         unsigned int max_rxsz;
  75         unsigned int llimit;
  76         unsigned int ulimit;
  77         unsigned int nppods;
  78         unsigned int idx_last;
  79         unsigned char idx_bits;
  80         unsigned char filler[3];
  81         u32 idx_mask;
  82         u32 rsvd_tag_mask;
  83         spinlock_t map_lock;
  84         struct cxgb3i_gather_list **gl_map;
  85         struct sk_buff **gl_skb;
  86 };
  87
  88 #define ULP2_MAX_PKT_SIZE       16224
  89 #define ULP2_MAX_PDU_PAYLOAD    (ULP2_MAX_PKT_SIZE - ISCSI_PDU_NONPAYLOAD_MAX)
  90 #define PPOD_PAGES_MAX          4
  91 #define PPOD_PAGES_SHIFT        2       /* 4 pages per pod */
  92
  93 /*
  94  * struct pagepod_hdr, pagepod - pagepod format
  95  */
  96 struct pagepod_hdr {
  97         u32 vld_tid;
  98         u32 pgsz_tag_clr;
  99         u32 maxoffset;
 100         u32 pgoffset;
 101         u64 rsvd;
 102 };
 103
 104 struct pagepod {
 105         struct pagepod_hdr hdr;
 106         u64 addr[PPOD_PAGES_MAX + 1];
 107 };
 108
 109 #define PPOD_SIZE               sizeof(struct pagepod)  /* 64 */
 110 #define PPOD_SIZE_SHIFT         6
 111
 112 #define PPOD_COLOR_SHIFT        0
 113 #define PPOD_COLOR_SIZE         6
 114 #define PPOD_COLOR_MASK         ((1 << PPOD_COLOR_SIZE) - 1)
 115
 116 #define PPOD_IDX_SHIFT          PPOD_COLOR_SIZE
 117 #define PPOD_IDX_MAX_SIZE       24
 118
 119 #define S_PPOD_TID    0
 120 #define M_PPOD_TID    0xFFFFFF
 121 #define V_PPOD_TID(x) ((x) << S_PPOD_TID)
 122
 123 #define S_PPOD_VALID    24
 124 #define V_PPOD_VALID(x) ((x) << S_PPOD_VALID)
 125 #define F_PPOD_VALID    V_PPOD_VALID(1U)
 126
 127 #define S_PPOD_COLOR    0
 128 #define M_PPOD_COLOR    0x3F
 129 #define V_PPOD_COLOR(x) ((x) << S_PPOD_COLOR)
 130
 131 #define S_PPOD_TAG    6
 132 #define M_PPOD_TAG    0xFFFFFF
 133 #define V_PPOD_TAG(x) ((x) << S_PPOD_TAG)
 134
 135 #define S_PPOD_PGSZ    30
 136 #define M_PPOD_PGSZ    0x3
 137 #define V_PPOD_PGSZ(x) ((x) << S_PPOD_PGSZ)
 138
 139 /*
 140  * large memory chunk allocation/release
 141  * use vmalloc() if kmalloc() fails
 142  */
 143 static inline void *cxgb3i_alloc_big_mem(unsigned int size,
 144                                          gfp_t gfp)
 145 {
 146         void *p = kmalloc(size, gfp);
 147         if (!p)
 148                 p = vmalloc(size);
 149         if (p)
 150                 memset(p, 0, size);
 151         return p;
 152 }
 153
 154 static inline void cxgb3i_free_big_mem(void *addr)
 155 {
 156         if (is_vmalloc_addr(addr))
 157                 vfree(addr);
 158         else
 159                 kfree(addr);
 160 }
 161
 162 /*
 163  * cxgb3i ddp tag are 32 bits, it consists of reserved bits used by h/w and
 164  * non-reserved bits that can be used by the iscsi s/w.
 165  * The reserved bits are identified by the rsvd_bits and rsvd_shift fields
 166  * in struct cxgb3i_tag_format.
 167  *
 168  * The upper most reserved bit can be used to check if a tag is ddp tag or not:
 169  *      if the bit is 0, the tag is a valid ddp tag
 170  */
 171
 172 /**
 173  * cxgb3i_is_ddp_tag - check if a given tag is a hw/ddp tag
 174  * @tformat: tag format information
 175  * @tag: tag to be checked
 176  *
 177  * return true if the tag is a ddp tag, false otherwise.
 178  */
 179 static inline int cxgb3i_is_ddp_tag(struct cxgb3i_tag_format *tformat, u32 tag)
 180 {
 181         return !(tag & (1 << (tformat->rsvd_bits + tformat->rsvd_shift - 1)));
 182 }
 183
 184 /**
 185  * cxgb3i_sw_tag_usable - check if a given s/w tag has enough bits left for
 186  *                        the reserved/hw bits
 187  * @tformat: tag format information
 188  * @sw_tag: s/w tag to be checked
 189  *
 190  * return true if the tag is a ddp tag, false otherwise.
 191  */
 192 static inline int cxgb3i_sw_tag_usable(struct cxgb3i_tag_format *tformat,
 193                                         u32 sw_tag)
 194 {
 195         sw_tag >>= (32 - tformat->rsvd_bits);
 196         return !sw_tag;
 197 }
 198
 199 /**
 200  * cxgb3i_set_non_ddp_tag - mark a given s/w tag as an invalid ddp tag
 201  * @tformat: tag format information
 202  * @sw_tag: s/w tag to be checked
 203  *
 204  * insert 1 at the upper most reserved bit to mark it as an invalid ddp tag.
 205  */
 206 static inline u32 cxgb3i_set_non_ddp_tag(struct cxgb3i_tag_format *tformat,
 207                                          u32 sw_tag)
 208 {
 209         unsigned char shift = tformat->rsvd_bits + tformat->rsvd_shift - 1;
 210         u32 mask = (1 << shift) - 1;
 211
 212         if (sw_tag && (sw_tag & ~mask)) {
 213                 u32 v1 = sw_tag & ((1 << shift) - 1);
 214                 u32 v2 = (sw_tag >> (shift - 1)) << shift;
 215
 216                 return v2 | v1 | 1 << shift;
 217         }
 218         return sw_tag | 1 << shift;
 219 }
 220
 221 /**
 222  * cxgb3i_ddp_tag_base - shift the s/w tag bits so that reserved bits are not
 223  *                       used.
 224  * @tformat: tag format information
 225  * @sw_tag: s/w tag to be checked
 226  */
 227 static inline u32 cxgb3i_ddp_tag_base(struct cxgb3i_tag_format *tformat,
 228                                       u32 sw_tag)
 229 {
 230         u32 mask = (1 << tformat->rsvd_shift) - 1;
 231
 232         if (sw_tag && (sw_tag & ~mask)) {
 233                 u32 v1 = sw_tag & mask;
 234                 u32 v2 = sw_tag >> tformat->rsvd_shift;
 235
 236                 v2 <<= tformat->rsvd_shift + tformat->rsvd_bits;
 237                 return v2 | v1;
 238         }
 239         return sw_tag;
 240 }
 241
 242 /**
 243  * cxgb3i_tag_rsvd_bits - get the reserved bits used by the h/w
 244  * @tformat: tag format information
 245  * @tag: tag to be checked
 246  *
 247  * return the reserved bits in the tag
 248  */
 249 static inline u32 cxgb3i_tag_rsvd_bits(struct cxgb3i_tag_format *tformat,
 250                                        u32 tag)
 251 {
 252         if (cxgb3i_is_ddp_tag(tformat, tag))
 253                 return (tag >> tformat->rsvd_shift) & tformat->rsvd_mask;
 254         return 0;
 255 }
 256
 257 /**
 258  * cxgb3i_tag_nonrsvd_bits - get the non-reserved bits used by the s/w
 259  * @tformat: tag format information
 260  * @tag: tag to be checked
 261  *
 262  * return the non-reserved bits in the tag.
 263  */
 264 static inline u32 cxgb3i_tag_nonrsvd_bits(struct cxgb3i_tag_format *tformat,
 265                                           u32 tag)
 266 {
 267         unsigned char shift = tformat->rsvd_bits + tformat->rsvd_shift - 1;
 268         u32 v1, v2;
 269
 270         if (cxgb3i_is_ddp_tag(tformat, tag)) {
 271                 v1 = tag & ((1 << tformat->rsvd_shift) - 1);
 272                 v2 = (tag >> (shift + 1)) << tformat->rsvd_shift;
 273         } else {
 274                 u32 mask = (1 << shift) - 1;
 275
 276                 tag &= ~(1 << shift);
 277                 v1 = tag & mask;
 278                 v2 = (tag >> 1) & ~mask;
 279         }
 280         return v1 | v2;
 281 }
 282
 283 int cxgb3i_ddp_tag_reserve(struct t3cdev *, unsigned int tid,
 284                            struct cxgb3i_tag_format *, u32 *tag,
 285                            struct cxgb3i_gather_list *, gfp_t gfp);
 286 void cxgb3i_ddp_tag_release(struct t3cdev *, u32 tag);
 287
 288 struct cxgb3i_gather_list *cxgb3i_ddp_make_gl(unsigned int xferlen,
 289                                 struct scatterlist *sgl,
 290                                 unsigned int sgcnt,
 291                                 struct pci_dev *pdev,
 292                                 gfp_t gfp);
 293 void cxgb3i_ddp_release_gl(struct cxgb3i_gather_list *gl,
 294                                 struct pci_dev *pdev);
 295
 296 int cxgb3i_setup_conn_host_pagesize(struct t3cdev *, unsigned int tid,
 297                                     int reply);
 298 int cxgb3i_setup_conn_pagesize(struct t3cdev *, unsigned int tid, int reply,
 299                                unsigned long pgsz);
 300 int cxgb3i_setup_conn_digest(struct t3cdev *, unsigned int tid,
 301                                 int hcrc, int dcrc, int reply);
 302 int cxgb3i_ddp_find_page_index(unsigned long pgsz);
 303 int cxgb3i_adapter_ddp_init(struct t3cdev *, struct cxgb3i_tag_format *,
 304                             unsigned int *txsz, unsigned int *rxsz);
 305 void cxgb3i_adapter_ddp_cleanup(struct t3cdev *);
 306 #endif