1/* 2 * hvcserver.c 3 * Copyright (C) 2004 Ryan S Arnold, IBM Corporation 4 * 5 * PPC64 virtual I/O console server support. 6 * 7 * This program is free software; you can redistribute it and/or modify 8 * it under the terms of the GNU General Public License as published by 9 * the Free Software Foundation; either version 2 of the License, or 10 * (at your option) any later version. 11 * 12 * This program is distributed in the hope that it will be useful, 13 * but WITHOUT ANY WARRANTY; without even the implied warranty of 14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 15 * GNU General Public License for more details. 16 * 17 * You should have received a copy of the GNU General Public License 18 * along with this program; if not, write to the Free Software 19 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 20 */ 21 22#include <linux/kernel.h> 23#include <linux/list.h> 24#include <linux/module.h> 25#include <linux/slab.h> 26 27#include <asm/hvcall.h> 28#include <asm/hvcserver.h> 29#include <asm/io.h> 30 31#define HVCS_ARCH_VERSION "1.0.0" 32 33MODULE_AUTHOR("Ryan S. Arnold <rsa@us.ibm.com>"); 34MODULE_DESCRIPTION("IBM hvcs ppc64 API"); 35MODULE_LICENSE("GPL"); 36MODULE_VERSION(HVCS_ARCH_VERSION); 37 38/* 39 * Convert arch specific return codes into relevant errnos. The hvcs 40 * functions aren't performance sensitive, so this conversion isn't an 41 * issue. 42 */ 43static int hvcs_convert(long to_convert) 44{ 45 switch (to_convert) { 46 case H_SUCCESS: 47 return 0; 48 case H_PARAMETER: 49 return -EINVAL; 50 case H_HARDWARE: 51 return -EIO; 52 case H_BUSY: 53 case H_LONG_BUSY_ORDER_1_MSEC: 54 case H_LONG_BUSY_ORDER_10_MSEC: 55 case H_LONG_BUSY_ORDER_100_MSEC: 56 case H_LONG_BUSY_ORDER_1_SEC: 57 case H_LONG_BUSY_ORDER_10_SEC: 58 case H_LONG_BUSY_ORDER_100_SEC: 59 return -EBUSY; 60 case H_FUNCTION: /* fall through */ 61 default: 62 return -EPERM; 63 } 64} 65 66/** 67 * hvcs_free_partner_info - free pi allocated by hvcs_get_partner_info 68 * @head: list_head pointer for an allocated list of partner info structs to 69 * free. 70 * 71 * This function is used to free the partner info list that was returned by 72 * calling hvcs_get_partner_info(). 73 */ 74int hvcs_free_partner_info(struct list_head *head) 75{ 76 struct hvcs_partner_info *pi; 77 struct list_head *element; 78 79 if (!head) 80 return -EINVAL; 81 82 while (!list_empty(head)) { 83 element = head->next; 84 pi = list_entry(element, struct hvcs_partner_info, node); 85 list_del(element); 86 kfree(pi); 87 } 88 89 return 0; 90} 91EXPORT_SYMBOL(hvcs_free_partner_info); 92 93/* Helper function for hvcs_get_partner_info */ 94static int hvcs_next_partner(uint32_t unit_address, 95 unsigned long last_p_partition_ID, 96 unsigned long last_p_unit_address, unsigned long *pi_buff) 97 98{ 99 long retval; 100 retval = plpar_hcall_norets(H_VTERM_PARTNER_INFO, unit_address, 101 last_p_partition_ID, 102 last_p_unit_address, virt_to_phys(pi_buff)); 103 return hvcs_convert(retval); 104} 105 106/** 107 * hvcs_get_partner_info - Get all of the partner info for a vty-server adapter 108 * @unit_address: The unit_address of the vty-server adapter for which this 109 * function is fetching partner info. 110 * @head: An initialized list_head pointer to an empty list to use to return the 111 * list of partner info fetched from the hypervisor to the caller. 112 * @pi_buff: A page sized buffer pre-allocated prior to calling this function 113 * that is to be used to be used by firmware as an iterator to keep track 114 * of the partner info retrieval. 115 * 116 * This function returns non-zero on success, or if there is no partner info. 117 * 118 * The pi_buff is pre-allocated prior to calling this function because this 119 * function may be called with a spin_lock held and kmalloc of a page is not 120 * recommended as GFP_ATOMIC. 121 * 122 * The first long of this buffer is used to store a partner unit address. The 123 * second long is used to store a partner partition ID and starting at 124 * pi_buff[2] is the 79 character Converged Location Code (diff size than the 125 * unsigned longs, hence the casting mumbo jumbo you see later). 126 * 127 * Invocation of this function should always be followed by an invocation of 128 * hvcs_free_partner_info() using a pointer to the SAME list head instance 129 * that was passed as a parameter to this function. 130 */ 131int hvcs_get_partner_info(uint32_t unit_address, struct list_head *head, 132 unsigned long *pi_buff) 133{ 134 /* 135 * Dealt with as longs because of the hcall interface even though the 136 * values are uint32_t. 137 */ 138 unsigned long last_p_partition_ID; 139 unsigned long last_p_unit_address; 140 struct hvcs_partner_info *next_partner_info = NULL; 141 int more = 1; 142 int retval; 143 144 memset(pi_buff, 0x00, PAGE_SIZE); 145 /* invalid parameters */ 146 if (!head || !pi_buff) 147 return -EINVAL; 148 149 last_p_partition_ID = last_p_unit_address = ~0UL; 150 INIT_LIST_HEAD(head); 151 152 do { 153 retval = hvcs_next_partner(unit_address, last_p_partition_ID, 154 last_p_unit_address, pi_buff); 155 if (retval) { 156 /* 157 * Don't indicate that we've failed if we have 158 * any list elements. 159 */ 160 if (!list_empty(head)) 161 return 0; 162 return retval; 163 } 164 165 last_p_partition_ID = pi_buff[0]; 166 last_p_unit_address = pi_buff[1]; 167 168 /* This indicates that there are no further partners */ 169 if (last_p_partition_ID == ~0UL 170 && last_p_unit_address == ~0UL) 171 break; 172 173 /* This is a very small struct and will be freed soon in 174 * hvcs_free_partner_info(). */ 175 next_partner_info = kmalloc(sizeof(struct hvcs_partner_info), 176 GFP_ATOMIC); 177 178 if (!next_partner_info) { 179 printk(KERN_WARNING "HVCONSOLE: kmalloc() failed to" 180 " allocate partner info struct.\n"); 181 hvcs_free_partner_info(head); 182 return -ENOMEM; 183 } 184 185 next_partner_info->unit_address 186 = (unsigned int)last_p_unit_address; 187 next_partner_info->partition_ID 188 = (unsigned int)last_p_partition_ID; 189 190 /* copy the Null-term char too */ 191 strncpy(&next_partner_info->location_code[0], 192 (char *)&pi_buff[2], 193 strlen((char *)&pi_buff[2]) + 1); 194 195 list_add_tail(&(next_partner_info->node), head); 196 next_partner_info = NULL; 197 198 } while (more); 199 200 return 0; 201} 202EXPORT_SYMBOL(hvcs_get_partner_info); 203 204/** 205 * hvcs_register_connection - establish a connection between this vty-server and 206 * a vty. 207 * @unit_address: The unit address of the vty-server adapter that is to be 208 * establish a connection. 209 * @p_partition_ID: The partition ID of the vty adapter that is to be connected. 210 * @p_unit_address: The unit address of the vty adapter to which the vty-server 211 * is to be connected. 212 * 213 * If this function is called once and -EINVAL is returned it may 214 * indicate that the partner info needs to be refreshed for the 215 * target unit address at which point the caller must invoke 216 * hvcs_get_partner_info() and then call this function again. If, 217 * for a second time, -EINVAL is returned then it indicates that 218 * there is probably already a partner connection registered to a 219 * different vty-server adapter. It is also possible that a second 220 * -EINVAL may indicate that one of the parms is not valid, for 221 * instance if the link was removed between the vty-server adapter 222 * and the vty adapter that you are trying to open. Don't shoot the 223 * messenger. Firmware implemented it this way. 224 */ 225int hvcs_register_connection( uint32_t unit_address, 226 uint32_t p_partition_ID, uint32_t p_unit_address) 227{ 228 long retval; 229 retval = plpar_hcall_norets(H_REGISTER_VTERM, unit_address, 230 p_partition_ID, p_unit_address); 231 return hvcs_convert(retval); 232} 233EXPORT_SYMBOL(hvcs_register_connection); 234 235/** 236 * hvcs_free_connection - free the connection between a vty-server and vty 237 * @unit_address: The unit address of the vty-server that is to have its 238 * connection severed. 239 * 240 * This function is used to free the partner connection between a vty-server 241 * adapter and a vty adapter. 242 * 243 * If -EBUSY is returned continue to call this function until 0 is returned. 244 */ 245int hvcs_free_connection(uint32_t unit_address) 246{ 247 long retval; 248 retval = plpar_hcall_norets(H_FREE_VTERM, unit_address); 249 return hvcs_convert(retval); 250} 251EXPORT_SYMBOL(hvcs_free_connection); 252