Hank Janssen | 3e7ee49 | 2009-07-13 16:02:34 -0700 | [diff] [blame] | 1 | /* |
| 2 | * |
| 3 | * Copyright (c) 2009, Microsoft Corporation. |
| 4 | * |
| 5 | * This program is free software; you can redistribute it and/or modify it |
| 6 | * under the terms and conditions of the GNU General Public License, |
| 7 | * version 2, as published by the Free Software Foundation. |
| 8 | * |
| 9 | * This program is distributed in the hope it will be useful, but WITHOUT |
| 10 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| 11 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for |
| 12 | * more details. |
| 13 | * |
| 14 | * You should have received a copy of the GNU General Public License along with |
| 15 | * this program; if not, write to the Free Software Foundation, Inc., 59 Temple |
| 16 | * Place - Suite 330, Boston, MA 02111-1307 USA. |
| 17 | * |
| 18 | * Authors: |
| 19 | * Haiyang Zhang <haiyangz@microsoft.com> |
| 20 | * Hank Janssen <hjanssen@microsoft.com> |
K. Y. Srinivasan | b2a5a58 | 2011-05-10 07:55:30 -0700 | [diff] [blame] | 21 | * K. Y. Srinivasan <kys@microsoft.com> |
Hank Janssen | 3e7ee49 | 2009-07-13 16:02:34 -0700 | [diff] [blame] | 22 | * |
| 23 | */ |
Hank Janssen | 0a46618 | 2011-03-29 13:58:47 -0700 | [diff] [blame] | 24 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
Hank Janssen | 3e7ee49 | 2009-07-13 16:02:34 -0700 | [diff] [blame] | 25 | |
Greg Kroah-Hartman | a0086dc | 2009-08-17 17:22:08 -0700 | [diff] [blame] | 26 | #include <linux/kernel.h> |
| 27 | #include <linux/mm.h> |
Greg Kroah-Hartman | 645954c | 2009-08-28 16:22:59 -0700 | [diff] [blame] | 28 | #include "logging.h" |
Greg Kroah-Hartman | 8f078ca | 2010-05-05 22:22:35 -0700 | [diff] [blame] | 29 | #include "ring_buffer.h" |
Hank Janssen | 3e7ee49 | 2009-07-13 16:02:34 -0700 | [diff] [blame] | 30 | |
Hank Janssen | 3e7ee49 | 2009-07-13 16:02:34 -0700 | [diff] [blame] | 31 | |
Bill Pemberton | 454f18a | 2009-07-27 16:47:24 -0400 | [diff] [blame] | 32 | /* #defines */ |
| 33 | |
| 34 | |
| 35 | /* Amount of space to write to */ |
Lars Lindley | 0686e4f | 2010-03-11 23:51:23 +0100 | [diff] [blame] | 36 | #define BYTES_AVAIL_TO_WRITE(r, w, z) ((w) >= (r)) ? ((z) - ((w) - (r))) : ((r) - (w)) |
Hank Janssen | 3e7ee49 | 2009-07-13 16:02:34 -0700 | [diff] [blame] | 37 | |
| 38 | |
K. Y. Srinivasan | b2a5a58 | 2011-05-10 07:55:30 -0700 | [diff] [blame] | 39 | /* |
| 40 | * |
| 41 | * hv_get_ringbuffer_availbytes() |
| 42 | * |
| 43 | * Get number of bytes available to read and to write to |
| 44 | * for the specified ring buffer |
| 45 | */ |
Hank Janssen | 3e7ee49 | 2009-07-13 16:02:34 -0700 | [diff] [blame] | 46 | static inline void |
K. Y. Srinivasan | 2b8a912 | 2011-05-10 07:55:29 -0700 | [diff] [blame] | 47 | hv_get_ringbuffer_availbytes(struct hv_ring_buffer_info *rbi, |
Haiyang Zhang | 1ac5864 | 2010-11-08 14:04:47 -0800 | [diff] [blame] | 48 | u32 *read, u32 *write) |
Hank Janssen | 3e7ee49 | 2009-07-13 16:02:34 -0700 | [diff] [blame] | 49 | { |
C. Bartlett | 4408f53 | 2010-02-03 15:34:27 +0000 | [diff] [blame] | 50 | u32 read_loc, write_loc; |
Hank Janssen | 3e7ee49 | 2009-07-13 16:02:34 -0700 | [diff] [blame] | 51 | |
Bill Pemberton | 454f18a | 2009-07-27 16:47:24 -0400 | [diff] [blame] | 52 | /* Capture the read/write indices before they changed */ |
Haiyang Zhang | 82f8bd4 | 2010-11-08 14:04:45 -0800 | [diff] [blame] | 53 | read_loc = rbi->ring_buffer->read_index; |
| 54 | write_loc = rbi->ring_buffer->write_index; |
Hank Janssen | 3e7ee49 | 2009-07-13 16:02:34 -0700 | [diff] [blame] | 55 | |
Haiyang Zhang | 82f8bd4 | 2010-11-08 14:04:45 -0800 | [diff] [blame] | 56 | *write = BYTES_AVAIL_TO_WRITE(read_loc, write_loc, rbi->ring_datasize); |
| 57 | *read = rbi->ring_datasize - *write; |
Hank Janssen | 3e7ee49 | 2009-07-13 16:02:34 -0700 | [diff] [blame] | 58 | } |
| 59 | |
K. Y. Srinivasan | b2a5a58 | 2011-05-10 07:55:30 -0700 | [diff] [blame] | 60 | /* |
| 61 | * hv_get_next_write_location() |
| 62 | * |
| 63 | * Get the next write location for the specified ring buffer |
| 64 | * |
| 65 | */ |
Greg Kroah-Hartman | 4d64311 | 2009-07-14 15:09:36 -0700 | [diff] [blame] | 66 | static inline u32 |
K. Y. Srinivasan | 2b8a912 | 2011-05-10 07:55:29 -0700 | [diff] [blame] | 67 | hv_get_next_write_location(struct hv_ring_buffer_info *ring_info) |
Hank Janssen | 3e7ee49 | 2009-07-13 16:02:34 -0700 | [diff] [blame] | 68 | { |
Haiyang Zhang | fc8c72e | 2010-11-08 14:04:46 -0800 | [diff] [blame] | 69 | u32 next = ring_info->ring_buffer->write_index; |
Hank Janssen | 3e7ee49 | 2009-07-13 16:02:34 -0700 | [diff] [blame] | 70 | |
Hank Janssen | 3e7ee49 | 2009-07-13 16:02:34 -0700 | [diff] [blame] | 71 | return next; |
| 72 | } |
| 73 | |
K. Y. Srinivasan | b2a5a58 | 2011-05-10 07:55:30 -0700 | [diff] [blame] | 74 | /* |
| 75 | * hv_set_next_write_location() |
| 76 | * |
| 77 | * Set the next write location for the specified ring buffer |
| 78 | * |
| 79 | */ |
Hank Janssen | 3e7ee49 | 2009-07-13 16:02:34 -0700 | [diff] [blame] | 80 | static inline void |
K. Y. Srinivasan | 2b8a912 | 2011-05-10 07:55:29 -0700 | [diff] [blame] | 81 | hv_set_next_write_location(struct hv_ring_buffer_info *ring_info, |
Haiyang Zhang | fc8c72e | 2010-11-08 14:04:46 -0800 | [diff] [blame] | 82 | u32 next_write_location) |
Hank Janssen | 3e7ee49 | 2009-07-13 16:02:34 -0700 | [diff] [blame] | 83 | { |
Haiyang Zhang | fc8c72e | 2010-11-08 14:04:46 -0800 | [diff] [blame] | 84 | ring_info->ring_buffer->write_index = next_write_location; |
Hank Janssen | 3e7ee49 | 2009-07-13 16:02:34 -0700 | [diff] [blame] | 85 | } |
| 86 | |
K. Y. Srinivasan | b2a5a58 | 2011-05-10 07:55:30 -0700 | [diff] [blame] | 87 | /* |
| 88 | * hv_get_next_read_location() |
| 89 | * |
| 90 | * Get the next read location for the specified ring buffer |
| 91 | */ |
Greg Kroah-Hartman | 4d64311 | 2009-07-14 15:09:36 -0700 | [diff] [blame] | 92 | static inline u32 |
K. Y. Srinivasan | 2b8a912 | 2011-05-10 07:55:29 -0700 | [diff] [blame] | 93 | hv_get_next_read_location(struct hv_ring_buffer_info *ring_info) |
Hank Janssen | 3e7ee49 | 2009-07-13 16:02:34 -0700 | [diff] [blame] | 94 | { |
Haiyang Zhang | fc8c72e | 2010-11-08 14:04:46 -0800 | [diff] [blame] | 95 | u32 next = ring_info->ring_buffer->read_index; |
Hank Janssen | 3e7ee49 | 2009-07-13 16:02:34 -0700 | [diff] [blame] | 96 | |
Hank Janssen | 3e7ee49 | 2009-07-13 16:02:34 -0700 | [diff] [blame] | 97 | return next; |
| 98 | } |
| 99 | |
K. Y. Srinivasan | b2a5a58 | 2011-05-10 07:55:30 -0700 | [diff] [blame] | 100 | /* |
| 101 | * hv_get_next_readlocation_withoffset() |
| 102 | * |
| 103 | * Get the next read location + offset for the specified ring buffer. |
| 104 | * This allows the caller to skip |
| 105 | */ |
Greg Kroah-Hartman | 4d64311 | 2009-07-14 15:09:36 -0700 | [diff] [blame] | 106 | static inline u32 |
K. Y. Srinivasan | 2b8a912 | 2011-05-10 07:55:29 -0700 | [diff] [blame] | 107 | hv_get_next_readlocation_withoffset(struct hv_ring_buffer_info *ring_info, |
Haiyang Zhang | 1ac5864 | 2010-11-08 14:04:47 -0800 | [diff] [blame] | 108 | u32 offset) |
Hank Janssen | 3e7ee49 | 2009-07-13 16:02:34 -0700 | [diff] [blame] | 109 | { |
Haiyang Zhang | fc8c72e | 2010-11-08 14:04:46 -0800 | [diff] [blame] | 110 | u32 next = ring_info->ring_buffer->read_index; |
Hank Janssen | 3e7ee49 | 2009-07-13 16:02:34 -0700 | [diff] [blame] | 111 | |
Haiyang Zhang | fc8c72e | 2010-11-08 14:04:46 -0800 | [diff] [blame] | 112 | next += offset; |
| 113 | next %= ring_info->ring_datasize; |
Hank Janssen | 3e7ee49 | 2009-07-13 16:02:34 -0700 | [diff] [blame] | 114 | |
| 115 | return next; |
| 116 | } |
| 117 | |
K. Y. Srinivasan | b2a5a58 | 2011-05-10 07:55:30 -0700 | [diff] [blame] | 118 | /* |
| 119 | * |
| 120 | * hv_set_next_read_location() |
| 121 | * |
| 122 | * Set the next read location for the specified ring buffer |
| 123 | * |
| 124 | */ |
Hank Janssen | 3e7ee49 | 2009-07-13 16:02:34 -0700 | [diff] [blame] | 125 | static inline void |
K. Y. Srinivasan | 2b8a912 | 2011-05-10 07:55:29 -0700 | [diff] [blame] | 126 | hv_set_next_read_location(struct hv_ring_buffer_info *ring_info, |
Haiyang Zhang | fc8c72e | 2010-11-08 14:04:46 -0800 | [diff] [blame] | 127 | u32 next_read_location) |
Hank Janssen | 3e7ee49 | 2009-07-13 16:02:34 -0700 | [diff] [blame] | 128 | { |
Haiyang Zhang | fc8c72e | 2010-11-08 14:04:46 -0800 | [diff] [blame] | 129 | ring_info->ring_buffer->read_index = next_read_location; |
Hank Janssen | 3e7ee49 | 2009-07-13 16:02:34 -0700 | [diff] [blame] | 130 | } |
| 131 | |
| 132 | |
K. Y. Srinivasan | b2a5a58 | 2011-05-10 07:55:30 -0700 | [diff] [blame] | 133 | /* |
| 134 | * |
| 135 | * hv_get_ring_buffer() |
| 136 | * |
| 137 | * Get the start of the ring buffer |
| 138 | */ |
Greg Kroah-Hartman | 8282c40 | 2009-07-14 15:06:28 -0700 | [diff] [blame] | 139 | static inline void * |
K. Y. Srinivasan | 2b8a912 | 2011-05-10 07:55:29 -0700 | [diff] [blame] | 140 | hv_get_ring_buffer(struct hv_ring_buffer_info *ring_info) |
Hank Janssen | 3e7ee49 | 2009-07-13 16:02:34 -0700 | [diff] [blame] | 141 | { |
Haiyang Zhang | fc8c72e | 2010-11-08 14:04:46 -0800 | [diff] [blame] | 142 | return (void *)ring_info->ring_buffer->buffer; |
Hank Janssen | 3e7ee49 | 2009-07-13 16:02:34 -0700 | [diff] [blame] | 143 | } |
| 144 | |
| 145 | |
K. Y. Srinivasan | b2a5a58 | 2011-05-10 07:55:30 -0700 | [diff] [blame] | 146 | /* |
| 147 | * |
| 148 | * hv_get_ring_buffersize() |
| 149 | * |
| 150 | * Get the size of the ring buffer |
| 151 | */ |
Greg Kroah-Hartman | 4d64311 | 2009-07-14 15:09:36 -0700 | [diff] [blame] | 152 | static inline u32 |
K. Y. Srinivasan | 2b8a912 | 2011-05-10 07:55:29 -0700 | [diff] [blame] | 153 | hv_get_ring_buffersize(struct hv_ring_buffer_info *ring_info) |
Hank Janssen | 3e7ee49 | 2009-07-13 16:02:34 -0700 | [diff] [blame] | 154 | { |
Haiyang Zhang | fc8c72e | 2010-11-08 14:04:46 -0800 | [diff] [blame] | 155 | return ring_info->ring_datasize; |
Hank Janssen | 3e7ee49 | 2009-07-13 16:02:34 -0700 | [diff] [blame] | 156 | } |
| 157 | |
K. Y. Srinivasan | b2a5a58 | 2011-05-10 07:55:30 -0700 | [diff] [blame] | 158 | /* |
| 159 | * |
| 160 | * hv_get_ring_bufferindices() |
| 161 | * |
| 162 | * Get the read and write indices as u64 of the specified ring buffer |
| 163 | * |
| 164 | */ |
Greg Kroah-Hartman | 5947143 | 2009-07-14 15:10:26 -0700 | [diff] [blame] | 165 | static inline u64 |
K. Y. Srinivasan | 2b8a912 | 2011-05-10 07:55:29 -0700 | [diff] [blame] | 166 | hv_get_ring_bufferindices(struct hv_ring_buffer_info *ring_info) |
Hank Janssen | 3e7ee49 | 2009-07-13 16:02:34 -0700 | [diff] [blame] | 167 | { |
Haiyang Zhang | fc8c72e | 2010-11-08 14:04:46 -0800 | [diff] [blame] | 168 | return (u64)ring_info->ring_buffer->write_index << 32; |
Hank Janssen | 3e7ee49 | 2009-07-13 16:02:34 -0700 | [diff] [blame] | 169 | } |
| 170 | |
| 171 | |
K. Y. Srinivasan | b2a5a58 | 2011-05-10 07:55:30 -0700 | [diff] [blame] | 172 | /* |
| 173 | * |
| 174 | * hv_dump_ring_info() |
| 175 | * |
| 176 | * Dump out to console the ring buffer info |
| 177 | * |
| 178 | */ |
K. Y. Srinivasan | 549bf93 | 2011-05-10 07:55:27 -0700 | [diff] [blame] | 179 | void hv_dump_ring_info(struct hv_ring_buffer_info *ring_info, char *prefix) |
Hank Janssen | 3e7ee49 | 2009-07-13 16:02:34 -0700 | [diff] [blame] | 180 | { |
Haiyang Zhang | fc8c72e | 2010-11-08 14:04:46 -0800 | [diff] [blame] | 181 | u32 bytes_avail_towrite; |
| 182 | u32 bytes_avail_toread; |
Hank Janssen | 3e7ee49 | 2009-07-13 16:02:34 -0700 | [diff] [blame] | 183 | |
K. Y. Srinivasan | 2b8a912 | 2011-05-10 07:55:29 -0700 | [diff] [blame] | 184 | hv_get_ringbuffer_availbytes(ring_info, |
Haiyang Zhang | fc8c72e | 2010-11-08 14:04:46 -0800 | [diff] [blame] | 185 | &bytes_avail_toread, |
| 186 | &bytes_avail_towrite); |
Hank Janssen | 3e7ee49 | 2009-07-13 16:02:34 -0700 | [diff] [blame] | 187 | |
C. Bartlett | 4408f53 | 2010-02-03 15:34:27 +0000 | [diff] [blame] | 188 | DPRINT(VMBUS, |
| 189 | DEBUG_RING_LVL, |
| 190 | "%s <<ringinfo %p buffer %p avail write %u " |
| 191 | "avail read %u read idx %u write idx %u>>", |
Haiyang Zhang | fc8c72e | 2010-11-08 14:04:46 -0800 | [diff] [blame] | 192 | prefix, |
| 193 | ring_info, |
| 194 | ring_info->ring_buffer->buffer, |
| 195 | bytes_avail_towrite, |
| 196 | bytes_avail_toread, |
| 197 | ring_info->ring_buffer->read_index, |
| 198 | ring_info->ring_buffer->write_index); |
Hank Janssen | 3e7ee49 | 2009-07-13 16:02:34 -0700 | [diff] [blame] | 199 | } |
| 200 | |
Bill Pemberton | 454f18a | 2009-07-27 16:47:24 -0400 | [diff] [blame] | 201 | |
K. Y. Srinivasan | 8f1136a | 2011-05-10 07:55:31 -0700 | [diff] [blame] | 202 | /* |
| 203 | * |
| 204 | * hv_copyfrom_ringbuffer() |
| 205 | * |
| 206 | * Helper routine to copy to source from ring buffer. |
| 207 | * Assume there is enough room. Handles wrap-around in src case only!! |
| 208 | * |
| 209 | */ |
| 210 | static u32 hv_copyfrom_ringbuffer( |
| 211 | struct hv_ring_buffer_info *ring_info, |
| 212 | void *dest, |
| 213 | u32 destlen, |
| 214 | u32 start_read_offset) |
| 215 | { |
| 216 | void *ring_buffer = hv_get_ring_buffer(ring_info); |
| 217 | u32 ring_buffer_size = hv_get_ring_buffersize(ring_info); |
| 218 | |
| 219 | u32 frag_len; |
| 220 | |
| 221 | /* wrap-around detected at the src */ |
| 222 | if (destlen > ring_buffer_size - start_read_offset) { |
| 223 | frag_len = ring_buffer_size - start_read_offset; |
| 224 | |
| 225 | memcpy(dest, ring_buffer + start_read_offset, frag_len); |
| 226 | memcpy(dest + frag_len, ring_buffer, destlen - frag_len); |
| 227 | } else |
| 228 | |
| 229 | memcpy(dest, ring_buffer + start_read_offset, destlen); |
| 230 | |
| 231 | |
| 232 | start_read_offset += destlen; |
| 233 | start_read_offset %= ring_buffer_size; |
| 234 | |
| 235 | return start_read_offset; |
| 236 | } |
| 237 | |
| 238 | |
K. Y. Srinivasan | 7581578 | 2011-05-10 07:55:32 -0700 | [diff] [blame] | 239 | /* |
| 240 | * |
| 241 | * hv_copyto_ringbuffer() |
| 242 | * |
| 243 | * Helper routine to copy from source to ring buffer. |
| 244 | * Assume there is enough room. Handles wrap-around in dest case only!! |
| 245 | * |
| 246 | */ |
| 247 | static u32 hv_copyto_ringbuffer( |
Haiyang Zhang | fc8c72e | 2010-11-08 14:04:46 -0800 | [diff] [blame] | 248 | struct hv_ring_buffer_info *ring_info, |
| 249 | u32 start_write_offset, |
| 250 | void *src, |
K. Y. Srinivasan | 7581578 | 2011-05-10 07:55:32 -0700 | [diff] [blame] | 251 | u32 srclen) |
| 252 | { |
| 253 | void *ring_buffer = hv_get_ring_buffer(ring_info); |
| 254 | u32 ring_buffer_size = hv_get_ring_buffersize(ring_info); |
| 255 | u32 frag_len; |
Hank Janssen | 3e7ee49 | 2009-07-13 16:02:34 -0700 | [diff] [blame] | 256 | |
K. Y. Srinivasan | 7581578 | 2011-05-10 07:55:32 -0700 | [diff] [blame] | 257 | /* wrap-around detected! */ |
| 258 | if (srclen > ring_buffer_size - start_write_offset) { |
| 259 | frag_len = ring_buffer_size - start_write_offset; |
| 260 | memcpy(ring_buffer + start_write_offset, src, frag_len); |
| 261 | memcpy(ring_buffer, src + frag_len, srclen - frag_len); |
| 262 | } else |
| 263 | memcpy(ring_buffer + start_write_offset, src, srclen); |
| 264 | |
| 265 | start_write_offset += srclen; |
| 266 | start_write_offset %= ring_buffer_size; |
| 267 | |
| 268 | return start_write_offset; |
| 269 | } |
Hank Janssen | 3e7ee49 | 2009-07-13 16:02:34 -0700 | [diff] [blame] | 270 | |
K. Y. Srinivasan | b2a5a58 | 2011-05-10 07:55:30 -0700 | [diff] [blame] | 271 | /* |
| 272 | * |
| 273 | * hv_ringbuffer_get_debuginfo() |
| 274 | * |
| 275 | * Get various debug metrics for the specified ring buffer |
| 276 | * |
| 277 | */ |
K. Y. Srinivasan | a75b61d | 2011-05-10 07:55:28 -0700 | [diff] [blame] | 278 | void hv_ringbuffer_get_debuginfo(struct hv_ring_buffer_info *ring_info, |
Greg Kroah-Hartman | 80682b7 | 2010-07-27 11:37:32 -0700 | [diff] [blame] | 279 | struct hv_ring_buffer_debug_info *debug_info) |
Hank Janssen | 3e7ee49 | 2009-07-13 16:02:34 -0700 | [diff] [blame] | 280 | { |
Haiyang Zhang | fc8c72e | 2010-11-08 14:04:46 -0800 | [diff] [blame] | 281 | u32 bytes_avail_towrite; |
| 282 | u32 bytes_avail_toread; |
Hank Janssen | 3e7ee49 | 2009-07-13 16:02:34 -0700 | [diff] [blame] | 283 | |
Haiyang Zhang | fc8c72e | 2010-11-08 14:04:46 -0800 | [diff] [blame] | 284 | if (ring_info->ring_buffer) { |
K. Y. Srinivasan | 2b8a912 | 2011-05-10 07:55:29 -0700 | [diff] [blame] | 285 | hv_get_ringbuffer_availbytes(ring_info, |
Haiyang Zhang | fc8c72e | 2010-11-08 14:04:46 -0800 | [diff] [blame] | 286 | &bytes_avail_toread, |
| 287 | &bytes_avail_towrite); |
Hank Janssen | 3e7ee49 | 2009-07-13 16:02:34 -0700 | [diff] [blame] | 288 | |
Haiyang Zhang | fc8c72e | 2010-11-08 14:04:46 -0800 | [diff] [blame] | 289 | debug_info->bytes_avail_toread = bytes_avail_toread; |
| 290 | debug_info->bytes_avail_towrite = bytes_avail_towrite; |
Haiyang Zhang | 82f8bd4 | 2010-11-08 14:04:45 -0800 | [diff] [blame] | 291 | debug_info->current_read_index = |
Haiyang Zhang | fc8c72e | 2010-11-08 14:04:46 -0800 | [diff] [blame] | 292 | ring_info->ring_buffer->read_index; |
Haiyang Zhang | 82f8bd4 | 2010-11-08 14:04:45 -0800 | [diff] [blame] | 293 | debug_info->current_write_index = |
Haiyang Zhang | fc8c72e | 2010-11-08 14:04:46 -0800 | [diff] [blame] | 294 | ring_info->ring_buffer->write_index; |
Haiyang Zhang | 82f8bd4 | 2010-11-08 14:04:45 -0800 | [diff] [blame] | 295 | debug_info->current_interrupt_mask = |
Haiyang Zhang | fc8c72e | 2010-11-08 14:04:46 -0800 | [diff] [blame] | 296 | ring_info->ring_buffer->interrupt_mask; |
Hank Janssen | 3e7ee49 | 2009-07-13 16:02:34 -0700 | [diff] [blame] | 297 | } |
| 298 | } |
| 299 | |
| 300 | |
K. Y. Srinivasan | b2a5a58 | 2011-05-10 07:55:30 -0700 | [diff] [blame] | 301 | /* |
| 302 | * |
| 303 | * hv_get_ringbuffer_interrupt_mask() |
| 304 | * |
| 305 | * Get the interrupt mask for the specified ring buffer |
| 306 | * |
| 307 | */ |
K. Y. Srinivasan | decc49d | 2011-05-10 07:55:26 -0700 | [diff] [blame] | 308 | u32 hv_get_ringbuffer_interrupt_mask(struct hv_ring_buffer_info *rbi) |
Hank Janssen | 3e7ee49 | 2009-07-13 16:02:34 -0700 | [diff] [blame] | 309 | { |
Haiyang Zhang | 82f8bd4 | 2010-11-08 14:04:45 -0800 | [diff] [blame] | 310 | return rbi->ring_buffer->interrupt_mask; |
Hank Janssen | 3e7ee49 | 2009-07-13 16:02:34 -0700 | [diff] [blame] | 311 | } |
| 312 | |
K. Y. Srinivasan | b2a5a58 | 2011-05-10 07:55:30 -0700 | [diff] [blame] | 313 | /* |
| 314 | * |
| 315 | * hv_ringbuffer_init() |
| 316 | * |
| 317 | *Initialize the ring buffer |
| 318 | * |
| 319 | */ |
K. Y. Srinivasan | 72a95cb | 2011-05-10 07:55:21 -0700 | [diff] [blame] | 320 | int hv_ringbuffer_init(struct hv_ring_buffer_info *ring_info, |
Haiyang Zhang | fc8c72e | 2010-11-08 14:04:46 -0800 | [diff] [blame] | 321 | void *buffer, u32 buflen) |
Hank Janssen | 3e7ee49 | 2009-07-13 16:02:34 -0700 | [diff] [blame] | 322 | { |
Greg Kroah-Hartman | 4a1b3ac | 2010-07-27 11:47:08 -0700 | [diff] [blame] | 323 | if (sizeof(struct hv_ring_buffer) != PAGE_SIZE) |
Bill Pemberton | 3324fb4 | 2010-05-05 15:27:49 -0400 | [diff] [blame] | 324 | return -EINVAL; |
Hank Janssen | 3e7ee49 | 2009-07-13 16:02:34 -0700 | [diff] [blame] | 325 | |
Haiyang Zhang | fc8c72e | 2010-11-08 14:04:46 -0800 | [diff] [blame] | 326 | memset(ring_info, 0, sizeof(struct hv_ring_buffer_info)); |
Hank Janssen | 3e7ee49 | 2009-07-13 16:02:34 -0700 | [diff] [blame] | 327 | |
Haiyang Zhang | fc8c72e | 2010-11-08 14:04:46 -0800 | [diff] [blame] | 328 | ring_info->ring_buffer = (struct hv_ring_buffer *)buffer; |
| 329 | ring_info->ring_buffer->read_index = |
| 330 | ring_info->ring_buffer->write_index = 0; |
Hank Janssen | 3e7ee49 | 2009-07-13 16:02:34 -0700 | [diff] [blame] | 331 | |
Haiyang Zhang | fc8c72e | 2010-11-08 14:04:46 -0800 | [diff] [blame] | 332 | ring_info->ring_size = buflen; |
| 333 | ring_info->ring_datasize = buflen - sizeof(struct hv_ring_buffer); |
Hank Janssen | 3e7ee49 | 2009-07-13 16:02:34 -0700 | [diff] [blame] | 334 | |
Haiyang Zhang | fc8c72e | 2010-11-08 14:04:46 -0800 | [diff] [blame] | 335 | spin_lock_init(&ring_info->ring_lock); |
Hank Janssen | 3e7ee49 | 2009-07-13 16:02:34 -0700 | [diff] [blame] | 336 | |
| 337 | return 0; |
| 338 | } |
| 339 | |
K. Y. Srinivasan | b2a5a58 | 2011-05-10 07:55:30 -0700 | [diff] [blame] | 340 | /* |
| 341 | * |
| 342 | * hv_ringbuffer_cleanup() |
| 343 | * |
| 344 | * Cleanup the ring buffer |
| 345 | * |
| 346 | */ |
K. Y. Srinivasan | 2dba688 | 2011-05-10 07:55:22 -0700 | [diff] [blame] | 347 | void hv_ringbuffer_cleanup(struct hv_ring_buffer_info *ring_info) |
Hank Janssen | 3e7ee49 | 2009-07-13 16:02:34 -0700 | [diff] [blame] | 348 | { |
Hank Janssen | 3e7ee49 | 2009-07-13 16:02:34 -0700 | [diff] [blame] | 349 | } |
| 350 | |
K. Y. Srinivasan | b2a5a58 | 2011-05-10 07:55:30 -0700 | [diff] [blame] | 351 | /* |
| 352 | * |
| 353 | * hv_ringbuffer_write() |
| 354 | * |
| 355 | * Write to the ring buffer |
| 356 | * |
| 357 | */ |
K. Y. Srinivasan | 633c4dc | 2011-05-10 07:55:23 -0700 | [diff] [blame] | 358 | int hv_ringbuffer_write(struct hv_ring_buffer_info *outring_info, |
Greg Kroah-Hartman | 3523a80 | 2009-08-17 17:22:08 -0700 | [diff] [blame] | 359 | struct scatterlist *sglist, u32 sgcount) |
Hank Janssen | 3e7ee49 | 2009-07-13 16:02:34 -0700 | [diff] [blame] | 360 | { |
C. Bartlett | 4408f53 | 2010-02-03 15:34:27 +0000 | [diff] [blame] | 361 | int i = 0; |
Haiyang Zhang | fc8c72e | 2010-11-08 14:04:46 -0800 | [diff] [blame] | 362 | u32 bytes_avail_towrite; |
| 363 | u32 bytes_avail_toread; |
| 364 | u32 totalbytes_towrite = 0; |
Hank Janssen | 3e7ee49 | 2009-07-13 16:02:34 -0700 | [diff] [blame] | 365 | |
Nicolas Palix | b219b3f | 2009-07-30 17:37:23 +0200 | [diff] [blame] | 366 | struct scatterlist *sg; |
K. Y. Srinivasan | 66a6054 | 2011-05-10 07:55:33 -0700 | [diff] [blame^] | 367 | u32 next_write_location; |
Haiyang Zhang | fc8c72e | 2010-11-08 14:04:46 -0800 | [diff] [blame] | 368 | u64 prev_indices = 0; |
Greg Kroah-Hartman | a98f96e | 2009-07-15 14:55:14 -0700 | [diff] [blame] | 369 | unsigned long flags; |
Hank Janssen | 3e7ee49 | 2009-07-13 16:02:34 -0700 | [diff] [blame] | 370 | |
Nicolas Palix | b219b3f | 2009-07-30 17:37:23 +0200 | [diff] [blame] | 371 | for_each_sg(sglist, sg, sgcount, i) |
Hank Janssen | 3e7ee49 | 2009-07-13 16:02:34 -0700 | [diff] [blame] | 372 | { |
Haiyang Zhang | fc8c72e | 2010-11-08 14:04:46 -0800 | [diff] [blame] | 373 | totalbytes_towrite += sg->length; |
Hank Janssen | 3e7ee49 | 2009-07-13 16:02:34 -0700 | [diff] [blame] | 374 | } |
| 375 | |
Haiyang Zhang | fc8c72e | 2010-11-08 14:04:46 -0800 | [diff] [blame] | 376 | totalbytes_towrite += sizeof(u64); |
Hank Janssen | 3e7ee49 | 2009-07-13 16:02:34 -0700 | [diff] [blame] | 377 | |
Haiyang Zhang | fc8c72e | 2010-11-08 14:04:46 -0800 | [diff] [blame] | 378 | spin_lock_irqsave(&outring_info->ring_lock, flags); |
Hank Janssen | 3e7ee49 | 2009-07-13 16:02:34 -0700 | [diff] [blame] | 379 | |
K. Y. Srinivasan | 2b8a912 | 2011-05-10 07:55:29 -0700 | [diff] [blame] | 380 | hv_get_ringbuffer_availbytes(outring_info, |
Haiyang Zhang | fc8c72e | 2010-11-08 14:04:46 -0800 | [diff] [blame] | 381 | &bytes_avail_toread, |
| 382 | &bytes_avail_towrite); |
Hank Janssen | 3e7ee49 | 2009-07-13 16:02:34 -0700 | [diff] [blame] | 383 | |
Hank Janssen | 3e7ee49 | 2009-07-13 16:02:34 -0700 | [diff] [blame] | 384 | |
C. Bartlett | 4408f53 | 2010-02-03 15:34:27 +0000 | [diff] [blame] | 385 | /* If there is only room for the packet, assume it is full. */ |
| 386 | /* Otherwise, the next time around, we think the ring buffer */ |
Bill Pemberton | 454f18a | 2009-07-27 16:47:24 -0400 | [diff] [blame] | 387 | /* is empty since the read index == write index */ |
Haiyang Zhang | fc8c72e | 2010-11-08 14:04:46 -0800 | [diff] [blame] | 388 | if (bytes_avail_towrite <= totalbytes_towrite) { |
Haiyang Zhang | fc8c72e | 2010-11-08 14:04:46 -0800 | [diff] [blame] | 389 | spin_unlock_irqrestore(&outring_info->ring_lock, flags); |
Hank Janssen | 3e7ee49 | 2009-07-13 16:02:34 -0700 | [diff] [blame] | 390 | return -1; |
| 391 | } |
| 392 | |
Bill Pemberton | 454f18a | 2009-07-27 16:47:24 -0400 | [diff] [blame] | 393 | /* Write to the ring buffer */ |
K. Y. Srinivasan | 2b8a912 | 2011-05-10 07:55:29 -0700 | [diff] [blame] | 394 | next_write_location = hv_get_next_write_location(outring_info); |
Hank Janssen | 3e7ee49 | 2009-07-13 16:02:34 -0700 | [diff] [blame] | 395 | |
Nicolas Palix | b219b3f | 2009-07-30 17:37:23 +0200 | [diff] [blame] | 396 | for_each_sg(sglist, sg, sgcount, i) |
Hank Janssen | 3e7ee49 | 2009-07-13 16:02:34 -0700 | [diff] [blame] | 397 | { |
K. Y. Srinivasan | 2b8a912 | 2011-05-10 07:55:29 -0700 | [diff] [blame] | 398 | next_write_location = hv_copyto_ringbuffer(outring_info, |
Haiyang Zhang | fc8c72e | 2010-11-08 14:04:46 -0800 | [diff] [blame] | 399 | next_write_location, |
Nicolas Palix | b219b3f | 2009-07-30 17:37:23 +0200 | [diff] [blame] | 400 | sg_virt(sg), |
| 401 | sg->length); |
Hank Janssen | 3e7ee49 | 2009-07-13 16:02:34 -0700 | [diff] [blame] | 402 | } |
| 403 | |
Bill Pemberton | 454f18a | 2009-07-27 16:47:24 -0400 | [diff] [blame] | 404 | /* Set previous packet start */ |
K. Y. Srinivasan | 2b8a912 | 2011-05-10 07:55:29 -0700 | [diff] [blame] | 405 | prev_indices = hv_get_ring_bufferindices(outring_info); |
Hank Janssen | 3e7ee49 | 2009-07-13 16:02:34 -0700 | [diff] [blame] | 406 | |
K. Y. Srinivasan | 2b8a912 | 2011-05-10 07:55:29 -0700 | [diff] [blame] | 407 | next_write_location = hv_copyto_ringbuffer(outring_info, |
Haiyang Zhang | fc8c72e | 2010-11-08 14:04:46 -0800 | [diff] [blame] | 408 | next_write_location, |
| 409 | &prev_indices, |
Nicolas Palix | b219b3f | 2009-07-30 17:37:23 +0200 | [diff] [blame] | 410 | sizeof(u64)); |
Hank Janssen | 3e7ee49 | 2009-07-13 16:02:34 -0700 | [diff] [blame] | 411 | |
Bill Pemberton | 454f18a | 2009-07-27 16:47:24 -0400 | [diff] [blame] | 412 | /* Make sure we flush all writes before updating the writeIndex */ |
Greg Kroah-Hartman | 28b6ca9 | 2009-07-16 12:34:20 -0700 | [diff] [blame] | 413 | mb(); |
Hank Janssen | 3e7ee49 | 2009-07-13 16:02:34 -0700 | [diff] [blame] | 414 | |
Bill Pemberton | 454f18a | 2009-07-27 16:47:24 -0400 | [diff] [blame] | 415 | /* Now, update the write location */ |
K. Y. Srinivasan | 2b8a912 | 2011-05-10 07:55:29 -0700 | [diff] [blame] | 416 | hv_set_next_write_location(outring_info, next_write_location); |
Hank Janssen | 3e7ee49 | 2009-07-13 16:02:34 -0700 | [diff] [blame] | 417 | |
Hank Janssen | 3e7ee49 | 2009-07-13 16:02:34 -0700 | [diff] [blame] | 418 | |
Haiyang Zhang | fc8c72e | 2010-11-08 14:04:46 -0800 | [diff] [blame] | 419 | spin_unlock_irqrestore(&outring_info->ring_lock, flags); |
Hank Janssen | 3e7ee49 | 2009-07-13 16:02:34 -0700 | [diff] [blame] | 420 | return 0; |
| 421 | } |
| 422 | |
| 423 | |
K. Y. Srinivasan | b2a5a58 | 2011-05-10 07:55:30 -0700 | [diff] [blame] | 424 | /* |
| 425 | * |
| 426 | * hv_ringbuffer_peek() |
| 427 | * |
| 428 | * Read without advancing the read index |
| 429 | * |
| 430 | */ |
K. Y. Srinivasan | a89186c | 2011-05-10 07:55:24 -0700 | [diff] [blame] | 431 | int hv_ringbuffer_peek(struct hv_ring_buffer_info *Inring_info, |
Haiyang Zhang | fc8c72e | 2010-11-08 14:04:46 -0800 | [diff] [blame] | 432 | void *Buffer, u32 buflen) |
Hank Janssen | 3e7ee49 | 2009-07-13 16:02:34 -0700 | [diff] [blame] | 433 | { |
Haiyang Zhang | fc8c72e | 2010-11-08 14:04:46 -0800 | [diff] [blame] | 434 | u32 bytes_avail_towrite; |
| 435 | u32 bytes_avail_toread; |
| 436 | u32 next_read_location = 0; |
Greg Kroah-Hartman | a98f96e | 2009-07-15 14:55:14 -0700 | [diff] [blame] | 437 | unsigned long flags; |
Hank Janssen | 3e7ee49 | 2009-07-13 16:02:34 -0700 | [diff] [blame] | 438 | |
Haiyang Zhang | fc8c72e | 2010-11-08 14:04:46 -0800 | [diff] [blame] | 439 | spin_lock_irqsave(&Inring_info->ring_lock, flags); |
Hank Janssen | 3e7ee49 | 2009-07-13 16:02:34 -0700 | [diff] [blame] | 440 | |
K. Y. Srinivasan | 2b8a912 | 2011-05-10 07:55:29 -0700 | [diff] [blame] | 441 | hv_get_ringbuffer_availbytes(Inring_info, |
Haiyang Zhang | fc8c72e | 2010-11-08 14:04:46 -0800 | [diff] [blame] | 442 | &bytes_avail_toread, |
| 443 | &bytes_avail_towrite); |
Hank Janssen | 3e7ee49 | 2009-07-13 16:02:34 -0700 | [diff] [blame] | 444 | |
Bill Pemberton | 454f18a | 2009-07-27 16:47:24 -0400 | [diff] [blame] | 445 | /* Make sure there is something to read */ |
Haiyang Zhang | fc8c72e | 2010-11-08 14:04:46 -0800 | [diff] [blame] | 446 | if (bytes_avail_toread < buflen) { |
Hank Janssen | 3e7ee49 | 2009-07-13 16:02:34 -0700 | [diff] [blame] | 447 | |
Haiyang Zhang | fc8c72e | 2010-11-08 14:04:46 -0800 | [diff] [blame] | 448 | spin_unlock_irqrestore(&Inring_info->ring_lock, flags); |
Hank Janssen | 3e7ee49 | 2009-07-13 16:02:34 -0700 | [diff] [blame] | 449 | |
| 450 | return -1; |
| 451 | } |
| 452 | |
Bill Pemberton | 454f18a | 2009-07-27 16:47:24 -0400 | [diff] [blame] | 453 | /* Convert to byte offset */ |
K. Y. Srinivasan | 2b8a912 | 2011-05-10 07:55:29 -0700 | [diff] [blame] | 454 | next_read_location = hv_get_next_read_location(Inring_info); |
Hank Janssen | 3e7ee49 | 2009-07-13 16:02:34 -0700 | [diff] [blame] | 455 | |
K. Y. Srinivasan | 2b8a912 | 2011-05-10 07:55:29 -0700 | [diff] [blame] | 456 | next_read_location = hv_copyfrom_ringbuffer(Inring_info, |
C. Bartlett | 4408f53 | 2010-02-03 15:34:27 +0000 | [diff] [blame] | 457 | Buffer, |
Haiyang Zhang | fc8c72e | 2010-11-08 14:04:46 -0800 | [diff] [blame] | 458 | buflen, |
| 459 | next_read_location); |
Hank Janssen | 3e7ee49 | 2009-07-13 16:02:34 -0700 | [diff] [blame] | 460 | |
Haiyang Zhang | fc8c72e | 2010-11-08 14:04:46 -0800 | [diff] [blame] | 461 | spin_unlock_irqrestore(&Inring_info->ring_lock, flags); |
Hank Janssen | 3e7ee49 | 2009-07-13 16:02:34 -0700 | [diff] [blame] | 462 | |
| 463 | return 0; |
| 464 | } |
| 465 | |
| 466 | |
K. Y. Srinivasan | b2a5a58 | 2011-05-10 07:55:30 -0700 | [diff] [blame] | 467 | /* |
| 468 | * |
| 469 | * hv_ringbuffer_read() |
| 470 | * |
| 471 | * Read and advance the read index |
| 472 | * |
| 473 | */ |
K. Y. Srinivasan | 38397c8 | 2011-05-10 07:55:25 -0700 | [diff] [blame] | 474 | int hv_ringbuffer_read(struct hv_ring_buffer_info *inring_info, void *buffer, |
Haiyang Zhang | fc8c72e | 2010-11-08 14:04:46 -0800 | [diff] [blame] | 475 | u32 buflen, u32 offset) |
Hank Janssen | 3e7ee49 | 2009-07-13 16:02:34 -0700 | [diff] [blame] | 476 | { |
Haiyang Zhang | fc8c72e | 2010-11-08 14:04:46 -0800 | [diff] [blame] | 477 | u32 bytes_avail_towrite; |
| 478 | u32 bytes_avail_toread; |
| 479 | u32 next_read_location = 0; |
| 480 | u64 prev_indices = 0; |
Greg Kroah-Hartman | a98f96e | 2009-07-15 14:55:14 -0700 | [diff] [blame] | 481 | unsigned long flags; |
Hank Janssen | 3e7ee49 | 2009-07-13 16:02:34 -0700 | [diff] [blame] | 482 | |
Haiyang Zhang | fc8c72e | 2010-11-08 14:04:46 -0800 | [diff] [blame] | 483 | if (buflen <= 0) |
Bill Pemberton | a16e148 | 2010-05-05 15:27:50 -0400 | [diff] [blame] | 484 | return -EINVAL; |
Hank Janssen | 3e7ee49 | 2009-07-13 16:02:34 -0700 | [diff] [blame] | 485 | |
Haiyang Zhang | fc8c72e | 2010-11-08 14:04:46 -0800 | [diff] [blame] | 486 | spin_lock_irqsave(&inring_info->ring_lock, flags); |
Hank Janssen | 3e7ee49 | 2009-07-13 16:02:34 -0700 | [diff] [blame] | 487 | |
K. Y. Srinivasan | 2b8a912 | 2011-05-10 07:55:29 -0700 | [diff] [blame] | 488 | hv_get_ringbuffer_availbytes(inring_info, |
Haiyang Zhang | fc8c72e | 2010-11-08 14:04:46 -0800 | [diff] [blame] | 489 | &bytes_avail_toread, |
| 490 | &bytes_avail_towrite); |
Hank Janssen | 3e7ee49 | 2009-07-13 16:02:34 -0700 | [diff] [blame] | 491 | |
Bill Pemberton | 454f18a | 2009-07-27 16:47:24 -0400 | [diff] [blame] | 492 | /* Make sure there is something to read */ |
Haiyang Zhang | fc8c72e | 2010-11-08 14:04:46 -0800 | [diff] [blame] | 493 | if (bytes_avail_toread < buflen) { |
Haiyang Zhang | fc8c72e | 2010-11-08 14:04:46 -0800 | [diff] [blame] | 494 | spin_unlock_irqrestore(&inring_info->ring_lock, flags); |
Hank Janssen | 3e7ee49 | 2009-07-13 16:02:34 -0700 | [diff] [blame] | 495 | |
| 496 | return -1; |
| 497 | } |
| 498 | |
Haiyang Zhang | 1ac5864 | 2010-11-08 14:04:47 -0800 | [diff] [blame] | 499 | next_read_location = |
K. Y. Srinivasan | 2b8a912 | 2011-05-10 07:55:29 -0700 | [diff] [blame] | 500 | hv_get_next_readlocation_withoffset(inring_info, offset); |
Hank Janssen | 3e7ee49 | 2009-07-13 16:02:34 -0700 | [diff] [blame] | 501 | |
K. Y. Srinivasan | 2b8a912 | 2011-05-10 07:55:29 -0700 | [diff] [blame] | 502 | next_read_location = hv_copyfrom_ringbuffer(inring_info, |
Haiyang Zhang | fc8c72e | 2010-11-08 14:04:46 -0800 | [diff] [blame] | 503 | buffer, |
| 504 | buflen, |
| 505 | next_read_location); |
Hank Janssen | 3e7ee49 | 2009-07-13 16:02:34 -0700 | [diff] [blame] | 506 | |
K. Y. Srinivasan | 2b8a912 | 2011-05-10 07:55:29 -0700 | [diff] [blame] | 507 | next_read_location = hv_copyfrom_ringbuffer(inring_info, |
Haiyang Zhang | fc8c72e | 2010-11-08 14:04:46 -0800 | [diff] [blame] | 508 | &prev_indices, |
C. Bartlett | 4408f53 | 2010-02-03 15:34:27 +0000 | [diff] [blame] | 509 | sizeof(u64), |
Haiyang Zhang | fc8c72e | 2010-11-08 14:04:46 -0800 | [diff] [blame] | 510 | next_read_location); |
Hank Janssen | 3e7ee49 | 2009-07-13 16:02:34 -0700 | [diff] [blame] | 511 | |
Bill Pemberton | 454f18a | 2009-07-27 16:47:24 -0400 | [diff] [blame] | 512 | /* Make sure all reads are done before we update the read index since */ |
C. Bartlett | 4408f53 | 2010-02-03 15:34:27 +0000 | [diff] [blame] | 513 | /* the writer may start writing to the read area once the read index */ |
| 514 | /*is updated */ |
Greg Kroah-Hartman | 28b6ca9 | 2009-07-16 12:34:20 -0700 | [diff] [blame] | 515 | mb(); |
Hank Janssen | 3e7ee49 | 2009-07-13 16:02:34 -0700 | [diff] [blame] | 516 | |
Bill Pemberton | 454f18a | 2009-07-27 16:47:24 -0400 | [diff] [blame] | 517 | /* Update the read index */ |
K. Y. Srinivasan | 2b8a912 | 2011-05-10 07:55:29 -0700 | [diff] [blame] | 518 | hv_set_next_read_location(inring_info, next_read_location); |
Hank Janssen | 3e7ee49 | 2009-07-13 16:02:34 -0700 | [diff] [blame] | 519 | |
Haiyang Zhang | fc8c72e | 2010-11-08 14:04:46 -0800 | [diff] [blame] | 520 | spin_unlock_irqrestore(&inring_info->ring_lock, flags); |
Hank Janssen | 3e7ee49 | 2009-07-13 16:02:34 -0700 | [diff] [blame] | 521 | |
| 522 | return 0; |
| 523 | } |