1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 * or http://www.opensolaris.org/os/licensing. 10 * See the License for the specific language governing permissions 11 * and limitations under the License. 12 * 13 * When distributing Covered Code, include this CDDL HEADER in each 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 * If applicable, add the following below this CDDL HEADER, with the 16 * fields enclosed by brackets "[]" replaced with your own identifying 17 * information: Portions Copyright [yyyy] [name of copyright owner] 18 * 19 * CDDL HEADER END 20 */ 21 22 /* 23 * Copyright 2007 Sun Microsystems, Inc. All rights reserved. 24 * Use is subject to license terms. 25 */ 26 27 #pragma ident "%Z%%M% %I% %E% SMI" 28 29 /* 30 * A simple wrapper around the balloon kernel thread to allow userland 31 * programs access to the balloon status. 32 */ 33 34 #include <sys/types.h> 35 #include <sys/file.h> 36 #include <sys/errno.h> 37 #include <sys/open.h> 38 #include <sys/cred.h> 39 #include <sys/conf.h> 40 #include <sys/stat.h> 41 #include <sys/modctl.h> 42 #include <sys/ddi.h> 43 #include <sys/sunddi.h> 44 #include <sys/hypervisor.h> 45 #include <sys/sysmacros.h> 46 #include <sys/balloon_impl.h> 47 48 static dev_info_t *balloon_devi; 49 50 /*ARGSUSED*/ 51 static int 52 balloon_getinfo(dev_info_t *devi, ddi_info_cmd_t cmd, void *arg, void **result) 53 { 54 if (getminor((dev_t)arg) != BALLOON_MINOR) 55 return (DDI_FAILURE); 56 57 switch (cmd) { 58 case DDI_INFO_DEVT2DEVINFO: 59 *result = balloon_devi; 60 break; 61 case DDI_INFO_DEVT2INSTANCE: 62 *result = 0; 63 break; 64 default: 65 return (DDI_FAILURE); 66 } 67 68 return (DDI_SUCCESS); 69 } 70 71 static int 72 balloon_attach(dev_info_t *devi, ddi_attach_cmd_t cmd) 73 { 74 if (cmd != DDI_ATTACH) 75 return (DDI_FAILURE); 76 77 if (ddi_create_minor_node(devi, ddi_get_name(devi), S_IFCHR, 78 ddi_get_instance(devi), DDI_PSEUDO, 0) != DDI_SUCCESS) 79 return (DDI_FAILURE); 80 81 balloon_devi = devi; 82 ddi_report_dev(devi); 83 return (DDI_SUCCESS); 84 } 85 86 static int 87 balloon_detach(dev_info_t *devi, ddi_detach_cmd_t cmd) 88 { 89 if (cmd != DDI_DETACH) 90 return (DDI_FAILURE); 91 ddi_remove_minor_node(devi, NULL); 92 balloon_devi = NULL; 93 return (DDI_SUCCESS); 94 } 95 96 /*ARGSUSED1*/ 97 static int 98 balloon_open(dev_t *dev, int flag, int otyp, cred_t *cr) 99 { 100 return (getminor(*dev) == BALLOON_MINOR ? 0 : ENXIO); 101 } 102 103 /* 104 * When asked for one of the balloon values, we simply query the balloon thread. 105 */ 106 /*ARGSUSED*/ 107 static int 108 balloon_ioctl(dev_t dev, int cmd, intptr_t arg, int mode, cred_t *cr, 109 int *rval_p) 110 { 111 int rval = 0; 112 size_t value; 113 114 switch (cmd) { 115 case BLN_IOCTL_CURRENT: 116 case BLN_IOCTL_TARGET: 117 case BLN_IOCTL_LOW: 118 case BLN_IOCTL_HIGH: 119 case BLN_IOCTL_LIMIT: 120 value = balloon_values(cmd); 121 if (ddi_copyout((void *)&value, (void *)arg, sizeof (value), 122 mode)) 123 return (EFAULT); 124 break; 125 default: 126 rval = EINVAL; 127 break; 128 } 129 return (rval); 130 } 131 132 static struct cb_ops balloon_cb_ops = { 133 balloon_open, 134 nulldev, /* close */ 135 nodev, /* strategy */ 136 nodev, /* print */ 137 nodev, /* dump */ 138 nodev, /* read */ 139 nodev, /* write */ 140 balloon_ioctl, /* ioctl */ 141 nodev, /* devmap */ 142 nodev, /* mmap */ 143 nodev, /* segmap */ 144 nochpoll, /* poll */ 145 ddi_prop_op, 146 NULL, 147 D_64BIT | D_MP, 148 CB_REV, 149 NULL, 150 NULL 151 }; 152 153 static struct dev_ops balloon_dv_ops = { 154 DEVO_REV, 155 0, 156 balloon_getinfo, 157 nulldev, /* identify */ 158 nulldev, /* probe */ 159 balloon_attach, 160 balloon_detach, 161 nodev, /* reset */ 162 &balloon_cb_ops, 163 NULL, /* struct bus_ops */ 164 NULL /* power */ 165 }; 166 167 static struct modldrv modldrv = { 168 &mod_driverops, 169 "balloon driver 1.1", 170 &balloon_dv_ops 171 }; 172 173 static struct modlinkage modl = { 174 MODREV_1, 175 { 176 (void *)&modldrv, 177 NULL /* null termination */ 178 } 179 }; 180 181 int 182 _init(void) 183 { 184 return (mod_install(&modl)); 185 } 186 187 int 188 _fini(void) 189 { 190 return (mod_remove(&modl)); 191 } 192 193 int 194 _info(struct modinfo *modinfo) 195 { 196 return (mod_info(&modl, modinfo)); 197 } 198