| 1 | #include <u.h> |
| 2 | #include <libc.h> |
| 3 | #include <ureg.h> |
| 4 | #include "dat.h" |
| 5 | #include "fns.h" |
| 6 | #include "linux.h" |
| 7 | |
| 8 | enum { |
| 9 | Index, |
| 10 | Type, |
| 11 | Flags, |
| 12 | DPL, |
| 13 | Base, |
| 14 | Limit, |
| 15 | Nfields, |
| 16 | }; |
| 17 | |
| 18 | static int |
| 19 | descempty(struct linux_user_desc *info) |
| 20 | { |
| 21 | return info->base_addr==0 && info->limit==0 && |
| 22 | info->contents==0 && info->read_exec_only==1 && |
| 23 | info->seg_32bit==0 && info->limit_in_pages==0 && |
| 24 | info->seg_not_present==1 && info->useable==0; |
| 25 | } |
| 26 | |
| 27 | int sys_set_thread_area(void *pinfo) |
| 28 | { |
| 29 | struct linux_user_desc *info = pinfo; |
| 30 | char buf[1024]; |
| 31 | char *p, *e, *f[Nfields]; |
| 32 | int n, fd, idx, err; |
| 33 | |
| 34 | trace("sys_set_thread_area(%p)", pinfo); |
| 35 | |
| 36 | err = -ENOSYS; |
| 37 | if((fd = open("/dev/gdt", ORDWR)) < 0) |
| 38 | goto out; |
| 39 | |
| 40 | idx = info->entry_number; |
| 41 | if(idx == -1){ |
| 42 | err = -ESRCH; |
| 43 | if((n = read(fd, buf, sizeof(buf)-1)) <= 0) |
| 44 | goto out; |
| 45 | buf[n] = 0; |
| 46 | p = buf; |
| 47 | while(e = strchr(p, '\n')){ |
| 48 | *e = 0; |
| 49 | if(getfields(p, f, nelem(f), 1, " ") != nelem(f)) |
| 50 | goto out; |
| 51 | idx = strtoul(f[Index], nil, 16); |
| 52 | if(idx >= 8*sizeof(current->tlsmask)) |
| 53 | break; |
| 54 | if((current->tlsmask & (1<<idx)) == 0) |
| 55 | goto found; |
| 56 | p = e+1; |
| 57 | } |
| 58 | goto out; |
| 59 | } |
| 60 | |
| 61 | found: |
| 62 | err = -EINVAL; |
| 63 | if(idx < 0 || idx >= 8*sizeof(current->tlsmask)) |
| 64 | goto out; |
| 65 | |
| 66 | buf[0] = 0; |
| 67 | if(!info->seg_not_present) |
| 68 | strcat(buf, "P"); |
| 69 | if(info->limit_in_pages) |
| 70 | strcat(buf, "G"); |
| 71 | if(info->useable) |
| 72 | strcat(buf, "U"); |
| 73 | if(info->contents & 2){ |
| 74 | /* code segment */ |
| 75 | if(info->contents & 1) |
| 76 | strcat(buf, "C"); |
| 77 | if(info->seg_32bit) |
| 78 | strcat(buf, "D"); |
| 79 | if(!info->read_exec_only) |
| 80 | strcat(buf, "R"); |
| 81 | if(buf[0] == 0) |
| 82 | strcat(buf, "-"); |
| 83 | |
| 84 | if(fprint(fd, "%x code %s 3 %lux %lux\n", |
| 85 | idx, buf, (ulong)info->base_addr, (ulong)info->limit) < 0) |
| 86 | goto out; |
| 87 | } else { |
| 88 | /* data segment */ |
| 89 | if(info->contents & 1) |
| 90 | strcat(buf, "E"); |
| 91 | if(info->seg_32bit) |
| 92 | strcat(buf, "B"); |
| 93 | if(!info->read_exec_only) |
| 94 | strcat(buf, "W"); |
| 95 | if(buf[0] == 0) |
| 96 | strcat(buf, "-"); |
| 97 | |
| 98 | if(fprint(fd, "%x data %s 3 %lux %lux\n", |
| 99 | idx, buf, (ulong)info->base_addr, (ulong)info->limit) < 0) |
| 100 | goto out; |
| 101 | } |
| 102 | |
| 103 | err = 0; |
| 104 | info->entry_number = idx; |
| 105 | if(!descempty(info)){ |
| 106 | current->tlsmask |= 1<<idx; |
| 107 | } else { |
| 108 | current->tlsmask &= ~(1<<idx); |
| 109 | } |
| 110 | |
| 111 | out: |
| 112 | if(fd >= 0) |
| 113 | close(fd); |
| 114 | return err; |
| 115 | } |
| 116 | |
| 117 | int sys_get_thread_area(void *pinfo) |
| 118 | { |
| 119 | struct linux_user_desc *info = pinfo; |
| 120 | int err, n, fd, idx; |
| 121 | char buf[1024]; |
| 122 | char *p, *e, *f[Nfields]; |
| 123 | |
| 124 | trace("sys_get_thread_area(%p)", pinfo); |
| 125 | |
| 126 | err = -ENOSYS; |
| 127 | if((fd = open("/dev/gdt", OREAD)) < 0) |
| 128 | goto out; |
| 129 | |
| 130 | err = -EINVAL; |
| 131 | if((n = read(fd, buf, sizeof(buf)-1)) <= 0) |
| 132 | goto out; |
| 133 | buf[n] = 0; |
| 134 | p = buf; |
| 135 | while(e = strchr(p, '\n')){ |
| 136 | *e = 0; |
| 137 | if(getfields(p, f, nelem(f), 1, " ") != nelem(f)) |
| 138 | goto out; |
| 139 | idx = strtoul(f[Index], nil, 16); |
| 140 | if(idx >= 8*sizeof(current->tlsmask)) |
| 141 | break; |
| 142 | if(idx == info->entry_number) |
| 143 | goto found; |
| 144 | p = e+1; |
| 145 | } |
| 146 | goto out; |
| 147 | |
| 148 | found: |
| 149 | info->contents = 0; |
| 150 | if(strcmp(f[Type], "code") == 0) |
| 151 | info->contents |= 2; |
| 152 | info->seg_not_present = 1; |
| 153 | info->limit_in_pages = 0; |
| 154 | info->seg_32bit = 0; |
| 155 | info->read_exec_only = 1; |
| 156 | info->useable = 0; |
| 157 | for(p = f[Flags]; *p; p++){ |
| 158 | switch(*p){ |
| 159 | case 'P': |
| 160 | info->seg_not_present = 0; |
| 161 | break; |
| 162 | case 'G': |
| 163 | info->limit_in_pages = 1; |
| 164 | break; |
| 165 | case 'B': |
| 166 | case 'D': |
| 167 | info->seg_32bit = 1; |
| 168 | break; |
| 169 | case 'W': |
| 170 | case 'R': |
| 171 | info->read_exec_only = 0; |
| 172 | break; |
| 173 | case 'U': |
| 174 | info->useable = 1; |
| 175 | break; |
| 176 | case 'E': |
| 177 | case 'C': |
| 178 | info->contents |= 1; |
| 179 | break; |
| 180 | } |
| 181 | } |
| 182 | |
| 183 | info->base_addr = strtoul(f[Base], nil, 16); |
| 184 | info->limit = strtoul(f[Limit], nil, 16); |
| 185 | |
| 186 | err = 0; |
| 187 | |
| 188 | out: |
| 189 | if(fd >= 0) |
| 190 | close(fd); |
| 191 | return err; |
| 192 | } |
| 193 | |
| 194 | static void |
| 195 | cleardesc(struct linux_user_desc *info) |
| 196 | { |
| 197 | info->base_addr=0; |
| 198 | info->limit=0; |
| 199 | info->contents=0; |
| 200 | info->read_exec_only=1; |
| 201 | info->seg_32bit=0; |
| 202 | info->limit_in_pages=0; |
| 203 | info->seg_not_present=1; |
| 204 | info->useable=0; |
| 205 | } |
| 206 | |
| 207 | void inittls(void) |
| 208 | { |
| 209 | struct linux_user_desc info; |
| 210 | int i; |
| 211 | |
| 212 | for(i=0; i<8*sizeof(current->tlsmask); i++){ |
| 213 | if((current->tlsmask & (1 << i)) == 0) |
| 214 | continue; |
| 215 | cleardesc(&info); |
| 216 | info.entry_number = i; |
| 217 | sys_set_thread_area(&info); |
| 218 | } |
| 219 | current->tlsmask = 0; |
| 220 | } |
| 221 | |
| 222 | void clonetls(Uproc *new) |
| 223 | { |
| 224 | new->tlsmask = current->tlsmask; |
| 225 | } |
| 226 | |
| 227 | int sys_modify_ldt(int func, void *data, int count) |
| 228 | { |
| 229 | trace("sys_modify_ldt(%d, %p, %x)", func, data, count); |
| 230 | |
| 231 | return -ENOSYS; |
| 232 | } |