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 2008 Sun Microsystems, Inc. All rights reserved. 24 * Use is subject to license terms. 25 */ 26 27 28 /* 29 * A simple wrapper around the balloon kernel thread to allow userland 30 * programs access to the balloon status. 31 */ 32 33 #include <sys/types.h> 34 #include <sys/file.h> 35 #include <sys/errno.h> 36 #include <sys/open.h> 37 #include <sys/cred.h> 38 #include <sys/conf.h> 39 #include <sys/stat.h> 40 #include <sys/modctl.h> 41 #include <sys/ddi.h> 42 #include <sys/sunddi.h> 43 #include <sys/hypervisor.h> 44 #include <sys/sysmacros.h> 45 #include <sys/balloon_impl.h> 46 47 static dev_info_t *balloon_devi; 48 49 /*ARGSUSED*/ 50 static int 51 balloon_getinfo(dev_info_t *devi, ddi_info_cmd_t cmd, void *arg, void **result) 52 { 53 if (getminor((dev_t)arg) != BALLOON_MINOR) 54 return (DDI_FAILURE); 55 56 switch (cmd) { 57 case DDI_INFO_DEVT2DEVINFO: 58 *result = balloon_devi; 59 break; 60 case DDI_INFO_DEVT2INSTANCE: 61 *result = 0; 62 break; 63 default: 64 return (DDI_FAILURE); 65 } 66 67 return (DDI_SUCCESS); 68 } 69 70 static int 71 balloon_attach(dev_info_t *devi, ddi_attach_cmd_t cmd) 72 { 73 if (cmd != DDI_ATTACH) 74 return (DDI_FAILURE); 75 76 if (ddi_create_minor_node(devi, ddi_get_name(devi), S_IFCHR, 77 ddi_get_instance(devi), DDI_PSEUDO, 0) != DDI_SUCCESS) 78 return (DDI_FAILURE); 79 80 balloon_devi = devi; 81 ddi_report_dev(devi); 82 return (DDI_SUCCESS); 83 } 84 85 static int 86 balloon_detach(dev_info_t *devi, ddi_detach_cmd_t cmd) 87 { 88 if (cmd != DDI_DETACH) 89 return (DDI_FAILURE); 90 ddi_remove_minor_node(devi, NULL); 91 balloon_devi = NULL; 92 return (DDI_SUCCESS); 93 } 94 95 /*ARGSUSED1*/ 96 static int 97 balloon_open(dev_t *dev, int flag, int otyp, cred_t *cr) 98 { 99 return (getminor(*dev) == BALLOON_MINOR ? 0 : ENXIO); 100 } 101 102 /* 103 * When asked for one of the balloon values, we simply query the balloon thread. 104 */ 105 /*ARGSUSED*/ 106 static int 107 balloon_ioctl(dev_t dev, int cmd, intptr_t arg, int mode, cred_t *cr, 108 int *rval_p) 109 { 110 int rval = 0; 111 size_t value; 112 113 switch (cmd) { 114 case BLN_IOCTL_CURRENT: 115 case BLN_IOCTL_TARGET: 116 case BLN_IOCTL_LOW: 117 case BLN_IOCTL_HIGH: 118 case BLN_IOCTL_LIMIT: 119 value = balloon_values(cmd); 120 if (ddi_copyout((void *)&value, (void *)arg, sizeof (value), 121 mode)) 122 return (EFAULT); 123 break; 124 default: 125 rval = EINVAL; 126 break; 127 } 128 return (rval); 129 } 130 131 static struct cb_ops balloon_cb_ops = { 132 balloon_open, 133 nulldev, /* close */ 134 nodev, /* strategy */ 135 nodev, /* print */ 136 nodev, /* dump */ 137 nodev, /* read */ 138 nodev, /* write */ 139 balloon_ioctl, /* ioctl */ 140 nodev, /* devmap */ 141 nodev, /* mmap */ 142 nodev, /* segmap */ 143 nochpoll, /* poll */ 144 ddi_prop_op, 145 NULL, 146 D_64BIT | D_MP, 147 CB_REV, 148 NULL, 149 NULL 150 }; 151 152 static struct dev_ops balloon_dv_ops = { 153 DEVO_REV, 154 0, 155 balloon_getinfo, 156 nulldev, /* identify */ 157 nulldev, /* probe */ 158 balloon_attach, 159 balloon_detach, 160 nodev, /* reset */ 161 &balloon_cb_ops, 162 NULL, /* struct bus_ops */ 163 NULL, /* power */ 164 ddi_quiesce_not_needed, /* quiesce */ 165 }; 166 167 static struct modldrv modldrv = { 168 &mod_driverops, 169 "balloon driver", 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