Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * This file contains the procedures for the handling of select and poll |
| 3 | * |
| 4 | * Created for Linux based loosely upon Mathius Lattner's minix |
| 5 | * patches by Peter MacDonald. Heavily edited by Linus. |
| 6 | * |
| 7 | * 4 February 1994 |
| 8 | * COFF/ELF binary emulation. If the process has the STICKY_TIMEOUTS |
| 9 | * flag set in its personality we do *not* modify the given timeout |
| 10 | * parameter to reflect time remaining. |
| 11 | * |
| 12 | * 24 January 2000 |
| 13 | * Changed sys_poll()/do_poll() to use PAGE_SIZE chunk-based allocation |
| 14 | * of fds to overcome nfds < 16390 descriptors limit (Tigran Aivazian). |
| 15 | */ |
| 16 | |
Milind Arun Choudhary | 022a169 | 2007-05-08 00:29:02 -0700 | [diff] [blame] | 17 | #include <linux/kernel.h> |
Alexey Dobriyan | a99bbaf | 2009-10-04 16:11:37 +0400 | [diff] [blame] | 18 | #include <linux/sched.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 19 | #include <linux/syscalls.h> |
Paul Gortmaker | 630d9c4 | 2011-11-16 23:57:37 -0500 | [diff] [blame] | 20 | #include <linux/export.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 21 | #include <linux/slab.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 22 | #include <linux/poll.h> |
| 23 | #include <linux/personality.h> /* for STICKY_TIMEOUTS */ |
| 24 | #include <linux/file.h> |
Al Viro | 9f3acc3 | 2008-04-24 07:44:08 -0400 | [diff] [blame] | 25 | #include <linux/fdtable.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 26 | #include <linux/fs.h> |
Dipankar Sarma | b835996 | 2005-09-09 13:04:14 -0700 | [diff] [blame] | 27 | #include <linux/rcupdate.h> |
Arjan van de Ven | 8ff3e8e | 2008-08-31 08:26:40 -0700 | [diff] [blame] | 28 | #include <linux/hrtimer.h> |
Clark Williams | 8bd75c7 | 2013-02-07 09:47:07 -0600 | [diff] [blame] | 29 | #include <linux/sched/rt.h> |
Eliezer Tamir | 2d48d67 | 2013-06-24 10:28:03 +0300 | [diff] [blame] | 30 | #include <net/ll_poll.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 31 | |
| 32 | #include <asm/uaccess.h> |
| 33 | |
Arjan van de Ven | 90d6e24 | 2008-09-01 15:55:35 -0700 | [diff] [blame] | 34 | |
| 35 | /* |
| 36 | * Estimate expected accuracy in ns from a timeval. |
| 37 | * |
| 38 | * After quite a bit of churning around, we've settled on |
| 39 | * a simple thing of taking 0.1% of the timeout as the |
| 40 | * slack, with a cap of 100 msec. |
| 41 | * "nice" tasks get a 0.5% slack instead. |
| 42 | * |
| 43 | * Consider this comment an open invitation to come up with even |
| 44 | * better solutions.. |
| 45 | */ |
| 46 | |
Guillaume Knispel | 5ae87e7 | 2009-09-22 16:43:30 -0700 | [diff] [blame] | 47 | #define MAX_SLACK (100 * NSEC_PER_MSEC) |
| 48 | |
Arjan van de Ven | 96d2ab4 | 2008-09-07 16:08:55 -0700 | [diff] [blame] | 49 | static long __estimate_accuracy(struct timespec *tv) |
Arjan van de Ven | 90d6e24 | 2008-09-01 15:55:35 -0700 | [diff] [blame] | 50 | { |
Arjan van de Ven | 96d2ab4 | 2008-09-07 16:08:55 -0700 | [diff] [blame] | 51 | long slack; |
Arjan van de Ven | 90d6e24 | 2008-09-01 15:55:35 -0700 | [diff] [blame] | 52 | int divfactor = 1000; |
| 53 | |
Guillaume Knispel | 5ae87e7 | 2009-09-22 16:43:30 -0700 | [diff] [blame] | 54 | if (tv->tv_sec < 0) |
| 55 | return 0; |
| 56 | |
Arjan van de Ven | 4ce105d | 2008-09-07 15:31:39 -0700 | [diff] [blame] | 57 | if (task_nice(current) > 0) |
Arjan van de Ven | 90d6e24 | 2008-09-01 15:55:35 -0700 | [diff] [blame] | 58 | divfactor = divfactor / 5; |
| 59 | |
Guillaume Knispel | 5ae87e7 | 2009-09-22 16:43:30 -0700 | [diff] [blame] | 60 | if (tv->tv_sec > MAX_SLACK / (NSEC_PER_SEC/divfactor)) |
| 61 | return MAX_SLACK; |
| 62 | |
Arjan van de Ven | 90d6e24 | 2008-09-01 15:55:35 -0700 | [diff] [blame] | 63 | slack = tv->tv_nsec / divfactor; |
| 64 | slack += tv->tv_sec * (NSEC_PER_SEC/divfactor); |
| 65 | |
Guillaume Knispel | 5ae87e7 | 2009-09-22 16:43:30 -0700 | [diff] [blame] | 66 | if (slack > MAX_SLACK) |
| 67 | return MAX_SLACK; |
Arjan van de Ven | 96d2ab4 | 2008-09-07 16:08:55 -0700 | [diff] [blame] | 68 | |
Arjan van de Ven | 90d6e24 | 2008-09-01 15:55:35 -0700 | [diff] [blame] | 69 | return slack; |
| 70 | } |
| 71 | |
Shawn Bohrer | 95aac7b | 2010-10-27 15:34:54 -0700 | [diff] [blame] | 72 | long select_estimate_accuracy(struct timespec *tv) |
Arjan van de Ven | 90d6e24 | 2008-09-01 15:55:35 -0700 | [diff] [blame] | 73 | { |
| 74 | unsigned long ret; |
| 75 | struct timespec now; |
| 76 | |
| 77 | /* |
| 78 | * Realtime tasks get a slack of 0 for obvious reasons. |
| 79 | */ |
| 80 | |
Arjan van de Ven | 4ce105d | 2008-09-07 15:31:39 -0700 | [diff] [blame] | 81 | if (rt_task(current)) |
Arjan van de Ven | 90d6e24 | 2008-09-01 15:55:35 -0700 | [diff] [blame] | 82 | return 0; |
| 83 | |
| 84 | ktime_get_ts(&now); |
| 85 | now = timespec_sub(*tv, now); |
| 86 | ret = __estimate_accuracy(&now); |
| 87 | if (ret < current->timer_slack_ns) |
| 88 | return current->timer_slack_ns; |
| 89 | return ret; |
| 90 | } |
| 91 | |
| 92 | |
| 93 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 94 | struct poll_table_page { |
| 95 | struct poll_table_page * next; |
| 96 | struct poll_table_entry * entry; |
| 97 | struct poll_table_entry entries[0]; |
| 98 | }; |
| 99 | |
| 100 | #define POLL_TABLE_FULL(table) \ |
| 101 | ((unsigned long)((table)->entry+1) > PAGE_SIZE + (unsigned long)(table)) |
| 102 | |
| 103 | /* |
| 104 | * Ok, Peter made a complicated, but straightforward multiple_wait() function. |
| 105 | * I have rewritten this, taking some shortcuts: This code may not be easy to |
| 106 | * follow, but it should be free of race-conditions, and it's practical. If you |
| 107 | * understand what I'm doing here, then you understand how the linux |
| 108 | * sleep/wakeup mechanism works. |
| 109 | * |
| 110 | * Two very simple procedures, poll_wait() and poll_freewait() make all the |
| 111 | * work. poll_wait() is an inline-function defined in <linux/poll.h>, |
| 112 | * as all select/poll functions have to call it to add an entry to the |
| 113 | * poll table. |
| 114 | */ |
Adrian Bunk | 75c96f8 | 2005-05-05 16:16:09 -0700 | [diff] [blame] | 115 | static void __pollwait(struct file *filp, wait_queue_head_t *wait_address, |
| 116 | poll_table *p); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 117 | |
| 118 | void poll_initwait(struct poll_wqueues *pwq) |
| 119 | { |
| 120 | init_poll_funcptr(&pwq->pt, __pollwait); |
Tejun Heo | 5f820f6 | 2009-01-06 14:40:59 -0800 | [diff] [blame] | 121 | pwq->polling_task = current; |
Guillaume Knispel | b2add73 | 2009-08-15 19:30:24 +0200 | [diff] [blame] | 122 | pwq->triggered = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 123 | pwq->error = 0; |
| 124 | pwq->table = NULL; |
Andi Kleen | 70674f9 | 2006-03-28 01:56:33 -0800 | [diff] [blame] | 125 | pwq->inline_index = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 126 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 127 | EXPORT_SYMBOL(poll_initwait); |
| 128 | |
Andi Kleen | 70674f9 | 2006-03-28 01:56:33 -0800 | [diff] [blame] | 129 | static void free_poll_entry(struct poll_table_entry *entry) |
| 130 | { |
WANG Cong | ccf6780 | 2007-05-09 07:10:02 +0200 | [diff] [blame] | 131 | remove_wait_queue(entry->wait_address, &entry->wait); |
Andi Kleen | 70674f9 | 2006-03-28 01:56:33 -0800 | [diff] [blame] | 132 | fput(entry->filp); |
| 133 | } |
| 134 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 135 | void poll_freewait(struct poll_wqueues *pwq) |
| 136 | { |
| 137 | struct poll_table_page * p = pwq->table; |
Andi Kleen | 70674f9 | 2006-03-28 01:56:33 -0800 | [diff] [blame] | 138 | int i; |
| 139 | for (i = 0; i < pwq->inline_index; i++) |
| 140 | free_poll_entry(pwq->inline_entries + i); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 141 | while (p) { |
| 142 | struct poll_table_entry * entry; |
| 143 | struct poll_table_page *old; |
| 144 | |
| 145 | entry = p->entry; |
| 146 | do { |
| 147 | entry--; |
Andi Kleen | 70674f9 | 2006-03-28 01:56:33 -0800 | [diff] [blame] | 148 | free_poll_entry(entry); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 149 | } while (entry > p->entries); |
| 150 | old = p; |
| 151 | p = p->next; |
| 152 | free_page((unsigned long) old); |
| 153 | } |
| 154 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 155 | EXPORT_SYMBOL(poll_freewait); |
| 156 | |
Tejun Heo | 5f820f6 | 2009-01-06 14:40:59 -0800 | [diff] [blame] | 157 | static struct poll_table_entry *poll_get_entry(struct poll_wqueues *p) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 158 | { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 159 | struct poll_table_page *table = p->table; |
| 160 | |
Andi Kleen | 70674f9 | 2006-03-28 01:56:33 -0800 | [diff] [blame] | 161 | if (p->inline_index < N_INLINE_POLL_ENTRIES) |
| 162 | return p->inline_entries + p->inline_index++; |
| 163 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 164 | if (!table || POLL_TABLE_FULL(table)) { |
| 165 | struct poll_table_page *new_table; |
| 166 | |
| 167 | new_table = (struct poll_table_page *) __get_free_page(GFP_KERNEL); |
| 168 | if (!new_table) { |
| 169 | p->error = -ENOMEM; |
Andi Kleen | 70674f9 | 2006-03-28 01:56:33 -0800 | [diff] [blame] | 170 | return NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 171 | } |
| 172 | new_table->entry = new_table->entries; |
| 173 | new_table->next = table; |
| 174 | p->table = new_table; |
| 175 | table = new_table; |
| 176 | } |
| 177 | |
Andi Kleen | 70674f9 | 2006-03-28 01:56:33 -0800 | [diff] [blame] | 178 | return table->entry++; |
| 179 | } |
| 180 | |
Eric Dumazet | 4938d7e | 2009-06-16 15:33:36 -0700 | [diff] [blame] | 181 | static int __pollwake(wait_queue_t *wait, unsigned mode, int sync, void *key) |
Tejun Heo | 5f820f6 | 2009-01-06 14:40:59 -0800 | [diff] [blame] | 182 | { |
| 183 | struct poll_wqueues *pwq = wait->private; |
| 184 | DECLARE_WAITQUEUE(dummy_wait, pwq->polling_task); |
| 185 | |
| 186 | /* |
| 187 | * Although this function is called under waitqueue lock, LOCK |
| 188 | * doesn't imply write barrier and the users expect write |
| 189 | * barrier semantics on wakeup functions. The following |
| 190 | * smp_wmb() is equivalent to smp_wmb() in try_to_wake_up() |
| 191 | * and is paired with set_mb() in poll_schedule_timeout. |
| 192 | */ |
| 193 | smp_wmb(); |
| 194 | pwq->triggered = 1; |
| 195 | |
| 196 | /* |
| 197 | * Perform the default wake up operation using a dummy |
| 198 | * waitqueue. |
| 199 | * |
| 200 | * TODO: This is hacky but there currently is no interface to |
| 201 | * pass in @sync. @sync is scheduled to be removed and once |
| 202 | * that happens, wake_up_process() can be used directly. |
| 203 | */ |
| 204 | return default_wake_function(&dummy_wait, mode, sync, key); |
| 205 | } |
| 206 | |
Eric Dumazet | 4938d7e | 2009-06-16 15:33:36 -0700 | [diff] [blame] | 207 | static int pollwake(wait_queue_t *wait, unsigned mode, int sync, void *key) |
| 208 | { |
| 209 | struct poll_table_entry *entry; |
| 210 | |
| 211 | entry = container_of(wait, struct poll_table_entry, wait); |
| 212 | if (key && !((unsigned long)key & entry->key)) |
| 213 | return 0; |
| 214 | return __pollwake(wait, mode, sync, key); |
| 215 | } |
| 216 | |
Andi Kleen | 70674f9 | 2006-03-28 01:56:33 -0800 | [diff] [blame] | 217 | /* Add a new entry */ |
| 218 | static void __pollwait(struct file *filp, wait_queue_head_t *wait_address, |
| 219 | poll_table *p) |
| 220 | { |
Tejun Heo | 5f820f6 | 2009-01-06 14:40:59 -0800 | [diff] [blame] | 221 | struct poll_wqueues *pwq = container_of(p, struct poll_wqueues, pt); |
| 222 | struct poll_table_entry *entry = poll_get_entry(pwq); |
Andi Kleen | 70674f9 | 2006-03-28 01:56:33 -0800 | [diff] [blame] | 223 | if (!entry) |
| 224 | return; |
Al Viro | cb0942b | 2012-08-27 14:48:26 -0400 | [diff] [blame] | 225 | entry->filp = get_file(filp); |
Andi Kleen | 70674f9 | 2006-03-28 01:56:33 -0800 | [diff] [blame] | 226 | entry->wait_address = wait_address; |
Hans Verkuil | 626cf23 | 2012-03-23 15:02:27 -0700 | [diff] [blame] | 227 | entry->key = p->_key; |
Tejun Heo | 5f820f6 | 2009-01-06 14:40:59 -0800 | [diff] [blame] | 228 | init_waitqueue_func_entry(&entry->wait, pollwake); |
| 229 | entry->wait.private = pwq; |
WANG Cong | ccf6780 | 2007-05-09 07:10:02 +0200 | [diff] [blame] | 230 | add_wait_queue(wait_address, &entry->wait); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 231 | } |
| 232 | |
Tejun Heo | 5f820f6 | 2009-01-06 14:40:59 -0800 | [diff] [blame] | 233 | int poll_schedule_timeout(struct poll_wqueues *pwq, int state, |
| 234 | ktime_t *expires, unsigned long slack) |
| 235 | { |
| 236 | int rc = -EINTR; |
| 237 | |
| 238 | set_current_state(state); |
| 239 | if (!pwq->triggered) |
| 240 | rc = schedule_hrtimeout_range(expires, slack, HRTIMER_MODE_ABS); |
| 241 | __set_current_state(TASK_RUNNING); |
| 242 | |
| 243 | /* |
| 244 | * Prepare for the next iteration. |
| 245 | * |
| 246 | * The following set_mb() serves two purposes. First, it's |
| 247 | * the counterpart rmb of the wmb in pollwake() such that data |
| 248 | * written before wake up is always visible after wake up. |
| 249 | * Second, the full barrier guarantees that triggered clearing |
| 250 | * doesn't pass event check of the next iteration. Note that |
| 251 | * this problem doesn't exist for the first iteration as |
| 252 | * add_wait_queue() has full barrier semantics. |
| 253 | */ |
| 254 | set_mb(pwq->triggered, 0); |
| 255 | |
| 256 | return rc; |
| 257 | } |
| 258 | EXPORT_SYMBOL(poll_schedule_timeout); |
| 259 | |
Thomas Gleixner | b773ad4 | 2008-08-31 08:16:57 -0700 | [diff] [blame] | 260 | /** |
| 261 | * poll_select_set_timeout - helper function to setup the timeout value |
| 262 | * @to: pointer to timespec variable for the final timeout |
| 263 | * @sec: seconds (from user space) |
| 264 | * @nsec: nanoseconds (from user space) |
| 265 | * |
| 266 | * Note, we do not use a timespec for the user space value here, That |
| 267 | * way we can use the function for timeval and compat interfaces as well. |
| 268 | * |
| 269 | * Returns -EINVAL if sec/nsec are not normalized. Otherwise 0. |
| 270 | */ |
| 271 | int poll_select_set_timeout(struct timespec *to, long sec, long nsec) |
| 272 | { |
| 273 | struct timespec ts = {.tv_sec = sec, .tv_nsec = nsec}; |
| 274 | |
| 275 | if (!timespec_valid(&ts)) |
| 276 | return -EINVAL; |
| 277 | |
| 278 | /* Optimize for the zero timeout value here */ |
| 279 | if (!sec && !nsec) { |
| 280 | to->tv_sec = to->tv_nsec = 0; |
| 281 | } else { |
| 282 | ktime_get_ts(to); |
| 283 | *to = timespec_add_safe(*to, ts); |
| 284 | } |
| 285 | return 0; |
| 286 | } |
| 287 | |
| 288 | static int poll_select_copy_remaining(struct timespec *end_time, void __user *p, |
| 289 | int timeval, int ret) |
| 290 | { |
| 291 | struct timespec rts; |
| 292 | struct timeval rtv; |
| 293 | |
| 294 | if (!p) |
| 295 | return ret; |
| 296 | |
| 297 | if (current->personality & STICKY_TIMEOUTS) |
| 298 | goto sticky; |
| 299 | |
| 300 | /* No update for zero timeout */ |
| 301 | if (!end_time->tv_sec && !end_time->tv_nsec) |
| 302 | return ret; |
| 303 | |
| 304 | ktime_get_ts(&rts); |
| 305 | rts = timespec_sub(*end_time, rts); |
| 306 | if (rts.tv_sec < 0) |
| 307 | rts.tv_sec = rts.tv_nsec = 0; |
| 308 | |
| 309 | if (timeval) { |
Vasiliy Kulikov | 65329bf | 2011-01-12 17:00:00 -0800 | [diff] [blame] | 310 | if (sizeof(rtv) > sizeof(rtv.tv_sec) + sizeof(rtv.tv_usec)) |
| 311 | memset(&rtv, 0, sizeof(rtv)); |
Thomas Gleixner | b773ad4 | 2008-08-31 08:16:57 -0700 | [diff] [blame] | 312 | rtv.tv_sec = rts.tv_sec; |
| 313 | rtv.tv_usec = rts.tv_nsec / NSEC_PER_USEC; |
| 314 | |
| 315 | if (!copy_to_user(p, &rtv, sizeof(rtv))) |
| 316 | return ret; |
| 317 | |
| 318 | } else if (!copy_to_user(p, &rts, sizeof(rts))) |
| 319 | return ret; |
| 320 | |
| 321 | /* |
| 322 | * If an application puts its timeval in read-only memory, we |
| 323 | * don't want the Linux-specific update to the timeval to |
| 324 | * cause a fault after the select has completed |
| 325 | * successfully. However, because we're not updating the |
| 326 | * timeval, we can't restart the system call. |
| 327 | */ |
| 328 | |
| 329 | sticky: |
| 330 | if (ret == -ERESTARTNOHAND) |
| 331 | ret = -EINTR; |
| 332 | return ret; |
| 333 | } |
| 334 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 335 | #define FDS_IN(fds, n) (fds->in + n) |
| 336 | #define FDS_OUT(fds, n) (fds->out + n) |
| 337 | #define FDS_EX(fds, n) (fds->ex + n) |
| 338 | |
| 339 | #define BITS(fds, n) (*FDS_IN(fds, n)|*FDS_OUT(fds, n)|*FDS_EX(fds, n)) |
| 340 | |
| 341 | static int max_select_fd(unsigned long n, fd_set_bits *fds) |
| 342 | { |
| 343 | unsigned long *open_fds; |
| 344 | unsigned long set; |
| 345 | int max; |
Dipankar Sarma | badf166 | 2005-09-09 13:04:10 -0700 | [diff] [blame] | 346 | struct fdtable *fdt; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 347 | |
| 348 | /* handle last in-complete long-word first */ |
Josh Boyer | 8ded2bb | 2012-07-25 10:40:34 -0400 | [diff] [blame] | 349 | set = ~(~0UL << (n & (BITS_PER_LONG-1))); |
| 350 | n /= BITS_PER_LONG; |
Dipankar Sarma | badf166 | 2005-09-09 13:04:10 -0700 | [diff] [blame] | 351 | fdt = files_fdtable(current->files); |
David Howells | 1fd36ad | 2012-02-16 17:49:54 +0000 | [diff] [blame] | 352 | open_fds = fdt->open_fds + n; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 353 | max = 0; |
| 354 | if (set) { |
| 355 | set &= BITS(fds, n); |
| 356 | if (set) { |
| 357 | if (!(set & ~*open_fds)) |
| 358 | goto get_max; |
| 359 | return -EBADF; |
| 360 | } |
| 361 | } |
| 362 | while (n) { |
| 363 | open_fds--; |
| 364 | n--; |
| 365 | set = BITS(fds, n); |
| 366 | if (!set) |
| 367 | continue; |
| 368 | if (set & ~*open_fds) |
| 369 | return -EBADF; |
| 370 | if (max) |
| 371 | continue; |
| 372 | get_max: |
| 373 | do { |
| 374 | max++; |
| 375 | set >>= 1; |
| 376 | } while (set); |
Josh Boyer | 8ded2bb | 2012-07-25 10:40:34 -0400 | [diff] [blame] | 377 | max += n * BITS_PER_LONG; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 378 | } |
| 379 | |
| 380 | return max; |
| 381 | } |
| 382 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 383 | #define POLLIN_SET (POLLRDNORM | POLLRDBAND | POLLIN | POLLHUP | POLLERR) |
| 384 | #define POLLOUT_SET (POLLWRBAND | POLLWRNORM | POLLOUT | POLLERR) |
| 385 | #define POLLEX_SET (POLLPRI) |
| 386 | |
Eric Dumazet | 4938d7e | 2009-06-16 15:33:36 -0700 | [diff] [blame] | 387 | static inline void wait_key_set(poll_table *wait, unsigned long in, |
Eliezer Tamir | 2d48d67 | 2013-06-24 10:28:03 +0300 | [diff] [blame] | 388 | unsigned long out, unsigned long bit, |
| 389 | unsigned int ll_flag) |
Eric Dumazet | 4938d7e | 2009-06-16 15:33:36 -0700 | [diff] [blame] | 390 | { |
Eliezer Tamir | 2d48d67 | 2013-06-24 10:28:03 +0300 | [diff] [blame] | 391 | wait->_key = POLLEX_SET | ll_flag; |
Hans Verkuil | 626cf23 | 2012-03-23 15:02:27 -0700 | [diff] [blame] | 392 | if (in & bit) |
| 393 | wait->_key |= POLLIN_SET; |
| 394 | if (out & bit) |
| 395 | wait->_key |= POLLOUT_SET; |
Eric Dumazet | 4938d7e | 2009-06-16 15:33:36 -0700 | [diff] [blame] | 396 | } |
| 397 | |
Arjan van de Ven | 8ff3e8e | 2008-08-31 08:26:40 -0700 | [diff] [blame] | 398 | int do_select(int n, fd_set_bits *fds, struct timespec *end_time) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 399 | { |
Arjan van de Ven | 8ff3e8e | 2008-08-31 08:26:40 -0700 | [diff] [blame] | 400 | ktime_t expire, *to = NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 401 | struct poll_wqueues table; |
| 402 | poll_table *wait; |
Arjan van de Ven | 8ff3e8e | 2008-08-31 08:26:40 -0700 | [diff] [blame] | 403 | int retval, i, timed_out = 0; |
Arjan van de Ven | 90d6e24 | 2008-09-01 15:55:35 -0700 | [diff] [blame] | 404 | unsigned long slack = 0; |
Eliezer Tamir | cbf5500 | 2013-07-08 16:20:34 +0300 | [diff] [blame^] | 405 | unsigned int busy_flag = net_busy_loop_on() ? POLL_BUSY_LOOP : 0; |
| 406 | u64 busy_start = busy_loop_start_time(busy_flag); |
| 407 | u64 busy_end = busy_loop_end_time(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 408 | |
Dipankar Sarma | b835996 | 2005-09-09 13:04:14 -0700 | [diff] [blame] | 409 | rcu_read_lock(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 410 | retval = max_select_fd(n, fds); |
Dipankar Sarma | b835996 | 2005-09-09 13:04:14 -0700 | [diff] [blame] | 411 | rcu_read_unlock(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 412 | |
| 413 | if (retval < 0) |
| 414 | return retval; |
| 415 | n = retval; |
| 416 | |
| 417 | poll_initwait(&table); |
| 418 | wait = &table.pt; |
Arjan van de Ven | 8ff3e8e | 2008-08-31 08:26:40 -0700 | [diff] [blame] | 419 | if (end_time && !end_time->tv_sec && !end_time->tv_nsec) { |
Hans Verkuil | 626cf23 | 2012-03-23 15:02:27 -0700 | [diff] [blame] | 420 | wait->_qproc = NULL; |
Arjan van de Ven | 8ff3e8e | 2008-08-31 08:26:40 -0700 | [diff] [blame] | 421 | timed_out = 1; |
| 422 | } |
| 423 | |
Arjan van de Ven | 96d2ab4 | 2008-09-07 16:08:55 -0700 | [diff] [blame] | 424 | if (end_time && !timed_out) |
Andrew Morton | 231f3d3 | 2010-10-27 15:34:53 -0700 | [diff] [blame] | 425 | slack = select_estimate_accuracy(end_time); |
Arjan van de Ven | 90d6e24 | 2008-09-01 15:55:35 -0700 | [diff] [blame] | 426 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 427 | retval = 0; |
| 428 | for (;;) { |
| 429 | unsigned long *rinp, *routp, *rexp, *inp, *outp, *exp; |
Eliezer Tamir | cbf5500 | 2013-07-08 16:20:34 +0300 | [diff] [blame^] | 430 | bool can_busy_loop = false; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 431 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 432 | inp = fds->in; outp = fds->out; exp = fds->ex; |
| 433 | rinp = fds->res_in; routp = fds->res_out; rexp = fds->res_ex; |
| 434 | |
| 435 | for (i = 0; i < n; ++rinp, ++routp, ++rexp) { |
| 436 | unsigned long in, out, ex, all_bits, bit = 1, mask, j; |
| 437 | unsigned long res_in = 0, res_out = 0, res_ex = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 438 | |
| 439 | in = *inp++; out = *outp++; ex = *exp++; |
| 440 | all_bits = in | out | ex; |
| 441 | if (all_bits == 0) { |
Josh Boyer | 8ded2bb | 2012-07-25 10:40:34 -0400 | [diff] [blame] | 442 | i += BITS_PER_LONG; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 443 | continue; |
| 444 | } |
| 445 | |
Josh Boyer | 8ded2bb | 2012-07-25 10:40:34 -0400 | [diff] [blame] | 446 | for (j = 0; j < BITS_PER_LONG; ++j, ++i, bit <<= 1) { |
Al Viro | 2903ff0 | 2012-08-28 12:52:22 -0400 | [diff] [blame] | 447 | struct fd f; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 448 | if (i >= n) |
| 449 | break; |
| 450 | if (!(bit & all_bits)) |
| 451 | continue; |
Al Viro | 2903ff0 | 2012-08-28 12:52:22 -0400 | [diff] [blame] | 452 | f = fdget(i); |
| 453 | if (f.file) { |
| 454 | const struct file_operations *f_op; |
| 455 | f_op = f.file->f_op; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 456 | mask = DEFAULT_POLLMASK; |
Eric Dumazet | 4938d7e | 2009-06-16 15:33:36 -0700 | [diff] [blame] | 457 | if (f_op && f_op->poll) { |
Eliezer Tamir | 2d48d67 | 2013-06-24 10:28:03 +0300 | [diff] [blame] | 458 | wait_key_set(wait, in, out, |
Eliezer Tamir | cbf5500 | 2013-07-08 16:20:34 +0300 | [diff] [blame^] | 459 | bit, busy_flag); |
Al Viro | 2903ff0 | 2012-08-28 12:52:22 -0400 | [diff] [blame] | 460 | mask = (*f_op->poll)(f.file, wait); |
Eric Dumazet | 4938d7e | 2009-06-16 15:33:36 -0700 | [diff] [blame] | 461 | } |
Al Viro | 2903ff0 | 2012-08-28 12:52:22 -0400 | [diff] [blame] | 462 | fdput(f); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 463 | if ((mask & POLLIN_SET) && (in & bit)) { |
| 464 | res_in |= bit; |
| 465 | retval++; |
Hans Verkuil | 626cf23 | 2012-03-23 15:02:27 -0700 | [diff] [blame] | 466 | wait->_qproc = NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 467 | } |
| 468 | if ((mask & POLLOUT_SET) && (out & bit)) { |
| 469 | res_out |= bit; |
| 470 | retval++; |
Hans Verkuil | 626cf23 | 2012-03-23 15:02:27 -0700 | [diff] [blame] | 471 | wait->_qproc = NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 472 | } |
| 473 | if ((mask & POLLEX_SET) && (ex & bit)) { |
| 474 | res_ex |= bit; |
| 475 | retval++; |
Hans Verkuil | 626cf23 | 2012-03-23 15:02:27 -0700 | [diff] [blame] | 476 | wait->_qproc = NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 477 | } |
Eliezer Tamir | 2d48d67 | 2013-06-24 10:28:03 +0300 | [diff] [blame] | 478 | /* got something, stop busy polling */ |
Eliezer Tamir | cbf5500 | 2013-07-08 16:20:34 +0300 | [diff] [blame^] | 479 | if (retval) { |
| 480 | can_busy_loop = false; |
| 481 | busy_flag = 0; |
| 482 | |
| 483 | /* |
| 484 | * only remember a returned |
| 485 | * POLL_BUSY_LOOP if we asked for it |
| 486 | */ |
| 487 | } else if (busy_flag & mask) |
| 488 | can_busy_loop = true; |
| 489 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 490 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 491 | } |
| 492 | if (res_in) |
| 493 | *rinp = res_in; |
| 494 | if (res_out) |
| 495 | *routp = res_out; |
| 496 | if (res_ex) |
| 497 | *rexp = res_ex; |
Linus Torvalds | 55d8538 | 2008-06-22 12:23:15 -0700 | [diff] [blame] | 498 | cond_resched(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 499 | } |
Hans Verkuil | 626cf23 | 2012-03-23 15:02:27 -0700 | [diff] [blame] | 500 | wait->_qproc = NULL; |
Arjan van de Ven | 8ff3e8e | 2008-08-31 08:26:40 -0700 | [diff] [blame] | 501 | if (retval || timed_out || signal_pending(current)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 502 | break; |
Pavel Machek | f526448 | 2008-04-21 22:15:06 +0000 | [diff] [blame] | 503 | if (table.error) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 504 | retval = table.error; |
| 505 | break; |
| 506 | } |
David Woodhouse | 9f72949 | 2006-01-18 17:44:05 -0800 | [diff] [blame] | 507 | |
Eliezer Tamir | cbf5500 | 2013-07-08 16:20:34 +0300 | [diff] [blame^] | 508 | /* only if found POLL_BUSY_LOOP sockets && not out of time */ |
| 509 | if (!need_resched() && can_busy_loop && |
| 510 | busy_loop_range(busy_start, busy_end)) |
Eliezer Tamir | 2d48d67 | 2013-06-24 10:28:03 +0300 | [diff] [blame] | 511 | continue; |
| 512 | |
Arjan van de Ven | 8ff3e8e | 2008-08-31 08:26:40 -0700 | [diff] [blame] | 513 | /* |
| 514 | * If this is the first loop and we have a timeout |
| 515 | * given, then we convert to ktime_t and set the to |
| 516 | * pointer to the expiry value. |
| 517 | */ |
| 518 | if (end_time && !to) { |
| 519 | expire = timespec_to_ktime(*end_time); |
| 520 | to = &expire; |
David Woodhouse | 9f72949 | 2006-01-18 17:44:05 -0800 | [diff] [blame] | 521 | } |
Arjan van de Ven | 8ff3e8e | 2008-08-31 08:26:40 -0700 | [diff] [blame] | 522 | |
Tejun Heo | 5f820f6 | 2009-01-06 14:40:59 -0800 | [diff] [blame] | 523 | if (!poll_schedule_timeout(&table, TASK_INTERRUPTIBLE, |
| 524 | to, slack)) |
Arjan van de Ven | 8ff3e8e | 2008-08-31 08:26:40 -0700 | [diff] [blame] | 525 | timed_out = 1; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 526 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 527 | |
| 528 | poll_freewait(&table); |
| 529 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 530 | return retval; |
| 531 | } |
| 532 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 533 | /* |
| 534 | * We can actually return ERESTARTSYS instead of EINTR, but I'd |
| 535 | * like to be certain this leads to no problems. So I return |
| 536 | * EINTR just for safety. |
| 537 | * |
| 538 | * Update: ERESTARTSYS breaks at least the xview clock binary, so |
| 539 | * I'm trying ERESTARTNOHAND which restart only when you want to. |
| 540 | */ |
Al Viro | a2dcb44 | 2008-04-23 14:05:15 -0400 | [diff] [blame] | 541 | int core_sys_select(int n, fd_set __user *inp, fd_set __user *outp, |
Arjan van de Ven | 8ff3e8e | 2008-08-31 08:26:40 -0700 | [diff] [blame] | 542 | fd_set __user *exp, struct timespec *end_time) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 543 | { |
| 544 | fd_set_bits fds; |
Andrew Morton | 29ff2db | 2006-04-10 22:52:46 -0700 | [diff] [blame] | 545 | void *bits; |
Vadim Lobanov | bbea9f6 | 2006-12-10 02:21:12 -0800 | [diff] [blame] | 546 | int ret, max_fds; |
Mitchell Blank Jr | b04eb6a | 2006-04-10 22:54:08 -0700 | [diff] [blame] | 547 | unsigned int size; |
Dipankar Sarma | badf166 | 2005-09-09 13:04:10 -0700 | [diff] [blame] | 548 | struct fdtable *fdt; |
Andi Kleen | 70674f9 | 2006-03-28 01:56:33 -0800 | [diff] [blame] | 549 | /* Allocate small arguments on the stack to save memory and be faster */ |
Jes Sorensen | 30c14e4 | 2006-03-31 11:18:57 -0500 | [diff] [blame] | 550 | long stack_fds[SELECT_STACK_ALLOC/sizeof(long)]; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 551 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 552 | ret = -EINVAL; |
| 553 | if (n < 0) |
| 554 | goto out_nofds; |
| 555 | |
Vadim Lobanov | bbea9f6 | 2006-12-10 02:21:12 -0800 | [diff] [blame] | 556 | /* max_fds can increase, so grab it once to avoid race */ |
Dipankar Sarma | b835996 | 2005-09-09 13:04:14 -0700 | [diff] [blame] | 557 | rcu_read_lock(); |
Dipankar Sarma | badf166 | 2005-09-09 13:04:10 -0700 | [diff] [blame] | 558 | fdt = files_fdtable(current->files); |
Vadim Lobanov | bbea9f6 | 2006-12-10 02:21:12 -0800 | [diff] [blame] | 559 | max_fds = fdt->max_fds; |
Dipankar Sarma | b835996 | 2005-09-09 13:04:14 -0700 | [diff] [blame] | 560 | rcu_read_unlock(); |
Vadim Lobanov | bbea9f6 | 2006-12-10 02:21:12 -0800 | [diff] [blame] | 561 | if (n > max_fds) |
| 562 | n = max_fds; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 563 | |
| 564 | /* |
| 565 | * We need 6 bitmaps (in/out/ex for both incoming and outgoing), |
| 566 | * since we used fdset we need to allocate memory in units of |
| 567 | * long-words. |
| 568 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 569 | size = FDS_BYTES(n); |
Mitchell Blank Jr | b04eb6a | 2006-04-10 22:54:08 -0700 | [diff] [blame] | 570 | bits = stack_fds; |
| 571 | if (size > sizeof(stack_fds) / 6) { |
| 572 | /* Not enough space in on-stack array; must use kmalloc */ |
| 573 | ret = -ENOMEM; |
Andi Kleen | 70674f9 | 2006-03-28 01:56:33 -0800 | [diff] [blame] | 574 | bits = kmalloc(6 * size, GFP_KERNEL); |
Mitchell Blank Jr | b04eb6a | 2006-04-10 22:54:08 -0700 | [diff] [blame] | 575 | if (!bits) |
| 576 | goto out_nofds; |
| 577 | } |
Andrew Morton | 29ff2db | 2006-04-10 22:52:46 -0700 | [diff] [blame] | 578 | fds.in = bits; |
| 579 | fds.out = bits + size; |
| 580 | fds.ex = bits + 2*size; |
| 581 | fds.res_in = bits + 3*size; |
| 582 | fds.res_out = bits + 4*size; |
| 583 | fds.res_ex = bits + 5*size; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 584 | |
| 585 | if ((ret = get_fd_set(n, inp, fds.in)) || |
| 586 | (ret = get_fd_set(n, outp, fds.out)) || |
| 587 | (ret = get_fd_set(n, exp, fds.ex))) |
| 588 | goto out; |
| 589 | zero_fd_set(n, fds.res_in); |
| 590 | zero_fd_set(n, fds.res_out); |
| 591 | zero_fd_set(n, fds.res_ex); |
| 592 | |
Arjan van de Ven | 8ff3e8e | 2008-08-31 08:26:40 -0700 | [diff] [blame] | 593 | ret = do_select(n, &fds, end_time); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 594 | |
| 595 | if (ret < 0) |
| 596 | goto out; |
| 597 | if (!ret) { |
| 598 | ret = -ERESTARTNOHAND; |
| 599 | if (signal_pending(current)) |
| 600 | goto out; |
| 601 | ret = 0; |
| 602 | } |
| 603 | |
| 604 | if (set_fd_set(n, inp, fds.res_in) || |
| 605 | set_fd_set(n, outp, fds.res_out) || |
| 606 | set_fd_set(n, exp, fds.res_ex)) |
| 607 | ret = -EFAULT; |
| 608 | |
| 609 | out: |
Andi Kleen | 70674f9 | 2006-03-28 01:56:33 -0800 | [diff] [blame] | 610 | if (bits != stack_fds) |
| 611 | kfree(bits); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 612 | out_nofds: |
| 613 | return ret; |
| 614 | } |
| 615 | |
Heiko Carstens | 5a8a82b | 2009-01-14 14:14:25 +0100 | [diff] [blame] | 616 | SYSCALL_DEFINE5(select, int, n, fd_set __user *, inp, fd_set __user *, outp, |
| 617 | fd_set __user *, exp, struct timeval __user *, tvp) |
David Woodhouse | 9f72949 | 2006-01-18 17:44:05 -0800 | [diff] [blame] | 618 | { |
Arjan van de Ven | 8ff3e8e | 2008-08-31 08:26:40 -0700 | [diff] [blame] | 619 | struct timespec end_time, *to = NULL; |
David Woodhouse | 9f72949 | 2006-01-18 17:44:05 -0800 | [diff] [blame] | 620 | struct timeval tv; |
| 621 | int ret; |
| 622 | |
| 623 | if (tvp) { |
| 624 | if (copy_from_user(&tv, tvp, sizeof(tv))) |
| 625 | return -EFAULT; |
| 626 | |
Arjan van de Ven | 8ff3e8e | 2008-08-31 08:26:40 -0700 | [diff] [blame] | 627 | to = &end_time; |
Arjan van de Ven | 4d36a9e | 2008-10-25 12:41:41 -0700 | [diff] [blame] | 628 | if (poll_select_set_timeout(to, |
| 629 | tv.tv_sec + (tv.tv_usec / USEC_PER_SEC), |
| 630 | (tv.tv_usec % USEC_PER_SEC) * NSEC_PER_USEC)) |
David Woodhouse | 9f72949 | 2006-01-18 17:44:05 -0800 | [diff] [blame] | 631 | return -EINVAL; |
David Woodhouse | 9f72949 | 2006-01-18 17:44:05 -0800 | [diff] [blame] | 632 | } |
| 633 | |
Arjan van de Ven | 8ff3e8e | 2008-08-31 08:26:40 -0700 | [diff] [blame] | 634 | ret = core_sys_select(n, inp, outp, exp, to); |
| 635 | ret = poll_select_copy_remaining(&end_time, tvp, 1, ret); |
David Woodhouse | 9f72949 | 2006-01-18 17:44:05 -0800 | [diff] [blame] | 636 | |
| 637 | return ret; |
| 638 | } |
| 639 | |
Heiko Carstens | c9da9f2 | 2009-01-14 14:13:57 +0100 | [diff] [blame] | 640 | static long do_pselect(int n, fd_set __user *inp, fd_set __user *outp, |
| 641 | fd_set __user *exp, struct timespec __user *tsp, |
| 642 | const sigset_t __user *sigmask, size_t sigsetsize) |
David Woodhouse | 9f72949 | 2006-01-18 17:44:05 -0800 | [diff] [blame] | 643 | { |
David Woodhouse | 9f72949 | 2006-01-18 17:44:05 -0800 | [diff] [blame] | 644 | sigset_t ksigmask, sigsaved; |
Arjan van de Ven | 8ff3e8e | 2008-08-31 08:26:40 -0700 | [diff] [blame] | 645 | struct timespec ts, end_time, *to = NULL; |
David Woodhouse | 9f72949 | 2006-01-18 17:44:05 -0800 | [diff] [blame] | 646 | int ret; |
| 647 | |
| 648 | if (tsp) { |
| 649 | if (copy_from_user(&ts, tsp, sizeof(ts))) |
| 650 | return -EFAULT; |
| 651 | |
Arjan van de Ven | 8ff3e8e | 2008-08-31 08:26:40 -0700 | [diff] [blame] | 652 | to = &end_time; |
| 653 | if (poll_select_set_timeout(to, ts.tv_sec, ts.tv_nsec)) |
David Woodhouse | 9f72949 | 2006-01-18 17:44:05 -0800 | [diff] [blame] | 654 | return -EINVAL; |
David Woodhouse | 9f72949 | 2006-01-18 17:44:05 -0800 | [diff] [blame] | 655 | } |
| 656 | |
| 657 | if (sigmask) { |
| 658 | /* XXX: Don't preclude handling different sized sigset_t's. */ |
| 659 | if (sigsetsize != sizeof(sigset_t)) |
| 660 | return -EINVAL; |
| 661 | if (copy_from_user(&ksigmask, sigmask, sizeof(ksigmask))) |
| 662 | return -EFAULT; |
| 663 | |
| 664 | sigdelsetmask(&ksigmask, sigmask(SIGKILL)|sigmask(SIGSTOP)); |
| 665 | sigprocmask(SIG_SETMASK, &ksigmask, &sigsaved); |
| 666 | } |
| 667 | |
Bernd Schmidt | 6256851 | 2009-01-13 22:14:48 +0100 | [diff] [blame] | 668 | ret = core_sys_select(n, inp, outp, exp, to); |
Arjan van de Ven | 8ff3e8e | 2008-08-31 08:26:40 -0700 | [diff] [blame] | 669 | ret = poll_select_copy_remaining(&end_time, tsp, 0, ret); |
David Woodhouse | 9f72949 | 2006-01-18 17:44:05 -0800 | [diff] [blame] | 670 | |
| 671 | if (ret == -ERESTARTNOHAND) { |
| 672 | /* |
| 673 | * Don't restore the signal mask yet. Let do_signal() deliver |
| 674 | * the signal on the way back to userspace, before the signal |
| 675 | * mask is restored. |
| 676 | */ |
| 677 | if (sigmask) { |
| 678 | memcpy(¤t->saved_sigmask, &sigsaved, |
| 679 | sizeof(sigsaved)); |
Roland McGrath | 4e4c22c | 2008-04-30 00:53:06 -0700 | [diff] [blame] | 680 | set_restore_sigmask(); |
David Woodhouse | 9f72949 | 2006-01-18 17:44:05 -0800 | [diff] [blame] | 681 | } |
| 682 | } else if (sigmask) |
| 683 | sigprocmask(SIG_SETMASK, &sigsaved, NULL); |
| 684 | |
| 685 | return ret; |
| 686 | } |
| 687 | |
| 688 | /* |
| 689 | * Most architectures can't handle 7-argument syscalls. So we provide a |
| 690 | * 6-argument version where the sixth argument is a pointer to a structure |
| 691 | * which has a pointer to the sigset_t itself followed by a size_t containing |
| 692 | * the sigset size. |
| 693 | */ |
Heiko Carstens | d4e8204 | 2009-01-14 14:14:34 +0100 | [diff] [blame] | 694 | SYSCALL_DEFINE6(pselect6, int, n, fd_set __user *, inp, fd_set __user *, outp, |
| 695 | fd_set __user *, exp, struct timespec __user *, tsp, |
| 696 | void __user *, sig) |
David Woodhouse | 9f72949 | 2006-01-18 17:44:05 -0800 | [diff] [blame] | 697 | { |
| 698 | size_t sigsetsize = 0; |
| 699 | sigset_t __user *up = NULL; |
| 700 | |
| 701 | if (sig) { |
| 702 | if (!access_ok(VERIFY_READ, sig, sizeof(void *)+sizeof(size_t)) |
Al Viro | e110ab9 | 2006-02-01 05:26:09 -0500 | [diff] [blame] | 703 | || __get_user(up, (sigset_t __user * __user *)sig) |
David Woodhouse | 9f72949 | 2006-01-18 17:44:05 -0800 | [diff] [blame] | 704 | || __get_user(sigsetsize, |
Al Viro | e110ab9 | 2006-02-01 05:26:09 -0500 | [diff] [blame] | 705 | (size_t __user *)(sig+sizeof(void *)))) |
David Woodhouse | 9f72949 | 2006-01-18 17:44:05 -0800 | [diff] [blame] | 706 | return -EFAULT; |
| 707 | } |
| 708 | |
Heiko Carstens | c9da9f2 | 2009-01-14 14:13:57 +0100 | [diff] [blame] | 709 | return do_pselect(n, inp, outp, exp, tsp, up, sigsetsize); |
David Woodhouse | 9f72949 | 2006-01-18 17:44:05 -0800 | [diff] [blame] | 710 | } |
David Woodhouse | 9f72949 | 2006-01-18 17:44:05 -0800 | [diff] [blame] | 711 | |
Christoph Hellwig | 5d0e528 | 2010-03-10 15:21:13 -0800 | [diff] [blame] | 712 | #ifdef __ARCH_WANT_SYS_OLD_SELECT |
| 713 | struct sel_arg_struct { |
| 714 | unsigned long n; |
| 715 | fd_set __user *inp, *outp, *exp; |
| 716 | struct timeval __user *tvp; |
| 717 | }; |
| 718 | |
| 719 | SYSCALL_DEFINE1(old_select, struct sel_arg_struct __user *, arg) |
| 720 | { |
| 721 | struct sel_arg_struct a; |
| 722 | |
| 723 | if (copy_from_user(&a, arg, sizeof(a))) |
| 724 | return -EFAULT; |
| 725 | return sys_select(a.n, a.inp, a.outp, a.exp, a.tvp); |
| 726 | } |
| 727 | #endif |
| 728 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 729 | struct poll_list { |
| 730 | struct poll_list *next; |
| 731 | int len; |
| 732 | struct pollfd entries[0]; |
| 733 | }; |
| 734 | |
| 735 | #define POLLFD_PER_PAGE ((PAGE_SIZE-sizeof(struct poll_list)) / sizeof(struct pollfd)) |
| 736 | |
Vadim Lobanov | 4a4b69f | 2006-06-23 02:05:16 -0700 | [diff] [blame] | 737 | /* |
| 738 | * Fish for pollable events on the pollfd->fd file descriptor. We're only |
| 739 | * interested in events matching the pollfd->events mask, and the result |
| 740 | * matching that mask is both recorded in pollfd->revents and returned. The |
| 741 | * pwait poll_table will be used by the fd-provided poll handler for waiting, |
Hans Verkuil | 626cf23 | 2012-03-23 15:02:27 -0700 | [diff] [blame] | 742 | * if pwait->_qproc is non-NULL. |
Vadim Lobanov | 4a4b69f | 2006-06-23 02:05:16 -0700 | [diff] [blame] | 743 | */ |
Eliezer Tamir | 2d48d67 | 2013-06-24 10:28:03 +0300 | [diff] [blame] | 744 | static inline unsigned int do_pollfd(struct pollfd *pollfd, poll_table *pwait, |
Eliezer Tamir | cbf5500 | 2013-07-08 16:20:34 +0300 | [diff] [blame^] | 745 | bool *can_busy_poll, |
| 746 | unsigned int busy_flag) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 747 | { |
Vadim Lobanov | 4a4b69f | 2006-06-23 02:05:16 -0700 | [diff] [blame] | 748 | unsigned int mask; |
| 749 | int fd; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 750 | |
Vadim Lobanov | 4a4b69f | 2006-06-23 02:05:16 -0700 | [diff] [blame] | 751 | mask = 0; |
| 752 | fd = pollfd->fd; |
| 753 | if (fd >= 0) { |
Al Viro | 2903ff0 | 2012-08-28 12:52:22 -0400 | [diff] [blame] | 754 | struct fd f = fdget(fd); |
Vadim Lobanov | 4a4b69f | 2006-06-23 02:05:16 -0700 | [diff] [blame] | 755 | mask = POLLNVAL; |
Al Viro | 2903ff0 | 2012-08-28 12:52:22 -0400 | [diff] [blame] | 756 | if (f.file) { |
Vadim Lobanov | 4a4b69f | 2006-06-23 02:05:16 -0700 | [diff] [blame] | 757 | mask = DEFAULT_POLLMASK; |
Al Viro | 2903ff0 | 2012-08-28 12:52:22 -0400 | [diff] [blame] | 758 | if (f.file->f_op && f.file->f_op->poll) { |
Hans Verkuil | 626cf23 | 2012-03-23 15:02:27 -0700 | [diff] [blame] | 759 | pwait->_key = pollfd->events|POLLERR|POLLHUP; |
Eliezer Tamir | cbf5500 | 2013-07-08 16:20:34 +0300 | [diff] [blame^] | 760 | pwait->_key |= busy_flag; |
Al Viro | 2903ff0 | 2012-08-28 12:52:22 -0400 | [diff] [blame] | 761 | mask = f.file->f_op->poll(f.file, pwait); |
Eliezer Tamir | cbf5500 | 2013-07-08 16:20:34 +0300 | [diff] [blame^] | 762 | if (mask & busy_flag) |
| 763 | *can_busy_poll = true; |
Eric Dumazet | 4938d7e | 2009-06-16 15:33:36 -0700 | [diff] [blame] | 764 | } |
Vadim Lobanov | 4a4b69f | 2006-06-23 02:05:16 -0700 | [diff] [blame] | 765 | /* Mask out unneeded events. */ |
| 766 | mask &= pollfd->events | POLLERR | POLLHUP; |
Al Viro | 2903ff0 | 2012-08-28 12:52:22 -0400 | [diff] [blame] | 767 | fdput(f); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 768 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 769 | } |
Vadim Lobanov | 4a4b69f | 2006-06-23 02:05:16 -0700 | [diff] [blame] | 770 | pollfd->revents = mask; |
| 771 | |
| 772 | return mask; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 773 | } |
| 774 | |
| 775 | static int do_poll(unsigned int nfds, struct poll_list *list, |
Arjan van de Ven | 8ff3e8e | 2008-08-31 08:26:40 -0700 | [diff] [blame] | 776 | struct poll_wqueues *wait, struct timespec *end_time) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 777 | { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 778 | poll_table* pt = &wait->pt; |
Arjan van de Ven | 8ff3e8e | 2008-08-31 08:26:40 -0700 | [diff] [blame] | 779 | ktime_t expire, *to = NULL; |
| 780 | int timed_out = 0, count = 0; |
Arjan van de Ven | 90d6e24 | 2008-09-01 15:55:35 -0700 | [diff] [blame] | 781 | unsigned long slack = 0; |
Eliezer Tamir | cbf5500 | 2013-07-08 16:20:34 +0300 | [diff] [blame^] | 782 | unsigned int busy_flag = net_busy_loop_on() ? POLL_BUSY_LOOP : 0; |
| 783 | u64 busy_start = busy_loop_start_time(busy_flag); |
| 784 | u64 busy_end = busy_loop_end_time(); |
| 785 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 786 | |
David Woodhouse | 9f72949 | 2006-01-18 17:44:05 -0800 | [diff] [blame] | 787 | /* Optimise the no-wait case */ |
Arjan van de Ven | 8ff3e8e | 2008-08-31 08:26:40 -0700 | [diff] [blame] | 788 | if (end_time && !end_time->tv_sec && !end_time->tv_nsec) { |
Hans Verkuil | 626cf23 | 2012-03-23 15:02:27 -0700 | [diff] [blame] | 789 | pt->_qproc = NULL; |
Arjan van de Ven | 8ff3e8e | 2008-08-31 08:26:40 -0700 | [diff] [blame] | 790 | timed_out = 1; |
| 791 | } |
Oleg Nesterov | 9bf084f | 2007-10-16 23:26:18 -0700 | [diff] [blame] | 792 | |
Arjan van de Ven | 96d2ab4 | 2008-09-07 16:08:55 -0700 | [diff] [blame] | 793 | if (end_time && !timed_out) |
Andrew Morton | 231f3d3 | 2010-10-27 15:34:53 -0700 | [diff] [blame] | 794 | slack = select_estimate_accuracy(end_time); |
Arjan van de Ven | 90d6e24 | 2008-09-01 15:55:35 -0700 | [diff] [blame] | 795 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 796 | for (;;) { |
| 797 | struct poll_list *walk; |
Eliezer Tamir | cbf5500 | 2013-07-08 16:20:34 +0300 | [diff] [blame^] | 798 | bool can_busy_loop = false; |
David Woodhouse | 9f72949 | 2006-01-18 17:44:05 -0800 | [diff] [blame] | 799 | |
Vadim Lobanov | 4a4b69f | 2006-06-23 02:05:16 -0700 | [diff] [blame] | 800 | for (walk = list; walk != NULL; walk = walk->next) { |
| 801 | struct pollfd * pfd, * pfd_end; |
| 802 | |
| 803 | pfd = walk->entries; |
| 804 | pfd_end = pfd + walk->len; |
| 805 | for (; pfd != pfd_end; pfd++) { |
| 806 | /* |
| 807 | * Fish for events. If we found one, record it |
Hans Verkuil | 626cf23 | 2012-03-23 15:02:27 -0700 | [diff] [blame] | 808 | * and kill poll_table->_qproc, so we don't |
Vadim Lobanov | 4a4b69f | 2006-06-23 02:05:16 -0700 | [diff] [blame] | 809 | * needlessly register any other waiters after |
| 810 | * this. They'll get immediately deregistered |
| 811 | * when we break out and return. |
| 812 | */ |
Eliezer Tamir | cbf5500 | 2013-07-08 16:20:34 +0300 | [diff] [blame^] | 813 | if (do_pollfd(pfd, pt, &can_busy_loop, |
| 814 | busy_flag)) { |
Vadim Lobanov | 4a4b69f | 2006-06-23 02:05:16 -0700 | [diff] [blame] | 815 | count++; |
Hans Verkuil | 626cf23 | 2012-03-23 15:02:27 -0700 | [diff] [blame] | 816 | pt->_qproc = NULL; |
Eliezer Tamir | cbf5500 | 2013-07-08 16:20:34 +0300 | [diff] [blame^] | 817 | /* found something, stop busy polling */ |
| 818 | busy_flag = 0; |
| 819 | can_busy_loop = false; |
Vadim Lobanov | 4a4b69f | 2006-06-23 02:05:16 -0700 | [diff] [blame] | 820 | } |
| 821 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 822 | } |
Vadim Lobanov | 4a4b69f | 2006-06-23 02:05:16 -0700 | [diff] [blame] | 823 | /* |
| 824 | * All waiters have already been registered, so don't provide |
Hans Verkuil | 626cf23 | 2012-03-23 15:02:27 -0700 | [diff] [blame] | 825 | * a poll_table->_qproc to them on the next loop iteration. |
Vadim Lobanov | 4a4b69f | 2006-06-23 02:05:16 -0700 | [diff] [blame] | 826 | */ |
Hans Verkuil | 626cf23 | 2012-03-23 15:02:27 -0700 | [diff] [blame] | 827 | pt->_qproc = NULL; |
Oleg Nesterov | 9bf084f | 2007-10-16 23:26:18 -0700 | [diff] [blame] | 828 | if (!count) { |
| 829 | count = wait->error; |
| 830 | if (signal_pending(current)) |
| 831 | count = -EINTR; |
| 832 | } |
Arjan van de Ven | 8ff3e8e | 2008-08-31 08:26:40 -0700 | [diff] [blame] | 833 | if (count || timed_out) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 834 | break; |
David Woodhouse | 9f72949 | 2006-01-18 17:44:05 -0800 | [diff] [blame] | 835 | |
Eliezer Tamir | cbf5500 | 2013-07-08 16:20:34 +0300 | [diff] [blame^] | 836 | /* only if found POLL_BUSY_LOOP sockets && not out of time */ |
| 837 | if (!need_resched() && can_busy_loop && |
| 838 | busy_loop_range(busy_start, busy_end)) |
Eliezer Tamir | 2d48d67 | 2013-06-24 10:28:03 +0300 | [diff] [blame] | 839 | continue; |
Eliezer Tamir | 91e2fd33 | 2013-06-28 15:59:35 +0300 | [diff] [blame] | 840 | |
Arjan van de Ven | 8ff3e8e | 2008-08-31 08:26:40 -0700 | [diff] [blame] | 841 | /* |
| 842 | * If this is the first loop and we have a timeout |
| 843 | * given, then we convert to ktime_t and set the to |
| 844 | * pointer to the expiry value. |
| 845 | */ |
| 846 | if (end_time && !to) { |
| 847 | expire = timespec_to_ktime(*end_time); |
| 848 | to = &expire; |
David Woodhouse | 9f72949 | 2006-01-18 17:44:05 -0800 | [diff] [blame] | 849 | } |
| 850 | |
Tejun Heo | 5f820f6 | 2009-01-06 14:40:59 -0800 | [diff] [blame] | 851 | if (!poll_schedule_timeout(wait, TASK_INTERRUPTIBLE, to, slack)) |
Arjan van de Ven | 8ff3e8e | 2008-08-31 08:26:40 -0700 | [diff] [blame] | 852 | timed_out = 1; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 853 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 854 | return count; |
| 855 | } |
| 856 | |
Andi Kleen | 70674f9 | 2006-03-28 01:56:33 -0800 | [diff] [blame] | 857 | #define N_STACK_PPS ((sizeof(stack_pps) - sizeof(struct poll_list)) / \ |
| 858 | sizeof(struct pollfd)) |
| 859 | |
Arjan van de Ven | 8ff3e8e | 2008-08-31 08:26:40 -0700 | [diff] [blame] | 860 | int do_sys_poll(struct pollfd __user *ufds, unsigned int nfds, |
| 861 | struct timespec *end_time) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 862 | { |
| 863 | struct poll_wqueues table; |
Oleg Nesterov | 252e572 | 2007-10-16 23:26:17 -0700 | [diff] [blame] | 864 | int err = -EFAULT, fdcount, len, size; |
Jes Sorensen | 30c14e4 | 2006-03-31 11:18:57 -0500 | [diff] [blame] | 865 | /* Allocate small arguments on the stack to save memory and be |
| 866 | faster - use long to make sure the buffer is aligned properly |
| 867 | on 64 bit archs to avoid unaligned access */ |
| 868 | long stack_pps[POLL_STACK_ALLOC/sizeof(long)]; |
Oleg Nesterov | 252e572 | 2007-10-16 23:26:17 -0700 | [diff] [blame] | 869 | struct poll_list *const head = (struct poll_list *)stack_pps; |
| 870 | struct poll_list *walk = head; |
| 871 | unsigned long todo = nfds; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 872 | |
Jiri Slaby | d554ed89 | 2010-03-05 13:42:42 -0800 | [diff] [blame] | 873 | if (nfds > rlimit(RLIMIT_NOFILE)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 874 | return -EINVAL; |
| 875 | |
Oleg Nesterov | 252e572 | 2007-10-16 23:26:17 -0700 | [diff] [blame] | 876 | len = min_t(unsigned int, nfds, N_STACK_PPS); |
| 877 | for (;;) { |
| 878 | walk->next = NULL; |
| 879 | walk->len = len; |
| 880 | if (!len) |
| 881 | break; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 882 | |
Oleg Nesterov | 252e572 | 2007-10-16 23:26:17 -0700 | [diff] [blame] | 883 | if (copy_from_user(walk->entries, ufds + nfds-todo, |
| 884 | sizeof(struct pollfd) * walk->len)) |
| 885 | goto out_fds; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 886 | |
Oleg Nesterov | 252e572 | 2007-10-16 23:26:17 -0700 | [diff] [blame] | 887 | todo -= walk->len; |
| 888 | if (!todo) |
| 889 | break; |
| 890 | |
| 891 | len = min(todo, POLLFD_PER_PAGE); |
| 892 | size = sizeof(struct poll_list) + sizeof(struct pollfd) * len; |
| 893 | walk = walk->next = kmalloc(size, GFP_KERNEL); |
| 894 | if (!walk) { |
| 895 | err = -ENOMEM; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 896 | goto out_fds; |
| 897 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 898 | } |
David Woodhouse | 9f72949 | 2006-01-18 17:44:05 -0800 | [diff] [blame] | 899 | |
Oleg Nesterov | 252e572 | 2007-10-16 23:26:17 -0700 | [diff] [blame] | 900 | poll_initwait(&table); |
Arjan van de Ven | 8ff3e8e | 2008-08-31 08:26:40 -0700 | [diff] [blame] | 901 | fdcount = do_poll(nfds, head, &table, end_time); |
Oleg Nesterov | 252e572 | 2007-10-16 23:26:17 -0700 | [diff] [blame] | 902 | poll_freewait(&table); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 903 | |
Oleg Nesterov | 252e572 | 2007-10-16 23:26:17 -0700 | [diff] [blame] | 904 | for (walk = head; walk; walk = walk->next) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 905 | struct pollfd *fds = walk->entries; |
| 906 | int j; |
| 907 | |
Oleg Nesterov | 252e572 | 2007-10-16 23:26:17 -0700 | [diff] [blame] | 908 | for (j = 0; j < walk->len; j++, ufds++) |
| 909 | if (__put_user(fds[j].revents, &ufds->revents)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 910 | goto out_fds; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 911 | } |
Oleg Nesterov | 252e572 | 2007-10-16 23:26:17 -0700 | [diff] [blame] | 912 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 913 | err = fdcount; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 914 | out_fds: |
Oleg Nesterov | 252e572 | 2007-10-16 23:26:17 -0700 | [diff] [blame] | 915 | walk = head->next; |
| 916 | while (walk) { |
| 917 | struct poll_list *pos = walk; |
| 918 | walk = walk->next; |
| 919 | kfree(pos); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 920 | } |
Oleg Nesterov | 252e572 | 2007-10-16 23:26:17 -0700 | [diff] [blame] | 921 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 922 | return err; |
| 923 | } |
David Woodhouse | 9f72949 | 2006-01-18 17:44:05 -0800 | [diff] [blame] | 924 | |
Chris Wright | 3075d9d | 2007-10-16 23:27:18 -0700 | [diff] [blame] | 925 | static long do_restart_poll(struct restart_block *restart_block) |
| 926 | { |
Arjan van de Ven | 8ff3e8e | 2008-08-31 08:26:40 -0700 | [diff] [blame] | 927 | struct pollfd __user *ufds = restart_block->poll.ufds; |
| 928 | int nfds = restart_block->poll.nfds; |
| 929 | struct timespec *to = NULL, end_time; |
Chris Wright | 3075d9d | 2007-10-16 23:27:18 -0700 | [diff] [blame] | 930 | int ret; |
| 931 | |
Arjan van de Ven | 8ff3e8e | 2008-08-31 08:26:40 -0700 | [diff] [blame] | 932 | if (restart_block->poll.has_timeout) { |
| 933 | end_time.tv_sec = restart_block->poll.tv_sec; |
| 934 | end_time.tv_nsec = restart_block->poll.tv_nsec; |
| 935 | to = &end_time; |
| 936 | } |
| 937 | |
| 938 | ret = do_sys_poll(ufds, nfds, to); |
| 939 | |
Chris Wright | 3075d9d | 2007-10-16 23:27:18 -0700 | [diff] [blame] | 940 | if (ret == -EINTR) { |
| 941 | restart_block->fn = do_restart_poll; |
Chris Wright | 3075d9d | 2007-10-16 23:27:18 -0700 | [diff] [blame] | 942 | ret = -ERESTART_RESTARTBLOCK; |
| 943 | } |
| 944 | return ret; |
| 945 | } |
| 946 | |
Heiko Carstens | 5a8a82b | 2009-01-14 14:14:25 +0100 | [diff] [blame] | 947 | SYSCALL_DEFINE3(poll, struct pollfd __user *, ufds, unsigned int, nfds, |
Linus Torvalds | faf3090 | 2012-02-21 17:24:20 -0800 | [diff] [blame] | 948 | int, timeout_msecs) |
David Woodhouse | 9f72949 | 2006-01-18 17:44:05 -0800 | [diff] [blame] | 949 | { |
Arjan van de Ven | 8ff3e8e | 2008-08-31 08:26:40 -0700 | [diff] [blame] | 950 | struct timespec end_time, *to = NULL; |
Chris Wright | 3075d9d | 2007-10-16 23:27:18 -0700 | [diff] [blame] | 951 | int ret; |
David Woodhouse | 9f72949 | 2006-01-18 17:44:05 -0800 | [diff] [blame] | 952 | |
Arjan van de Ven | 8ff3e8e | 2008-08-31 08:26:40 -0700 | [diff] [blame] | 953 | if (timeout_msecs >= 0) { |
| 954 | to = &end_time; |
| 955 | poll_select_set_timeout(to, timeout_msecs / MSEC_PER_SEC, |
| 956 | NSEC_PER_MSEC * (timeout_msecs % MSEC_PER_SEC)); |
David Woodhouse | 9f72949 | 2006-01-18 17:44:05 -0800 | [diff] [blame] | 957 | } |
| 958 | |
Arjan van de Ven | 8ff3e8e | 2008-08-31 08:26:40 -0700 | [diff] [blame] | 959 | ret = do_sys_poll(ufds, nfds, to); |
| 960 | |
Chris Wright | 3075d9d | 2007-10-16 23:27:18 -0700 | [diff] [blame] | 961 | if (ret == -EINTR) { |
| 962 | struct restart_block *restart_block; |
Arjan van de Ven | 8ff3e8e | 2008-08-31 08:26:40 -0700 | [diff] [blame] | 963 | |
Chris Wright | 3075d9d | 2007-10-16 23:27:18 -0700 | [diff] [blame] | 964 | restart_block = ¤t_thread_info()->restart_block; |
| 965 | restart_block->fn = do_restart_poll; |
Arjan van de Ven | 8ff3e8e | 2008-08-31 08:26:40 -0700 | [diff] [blame] | 966 | restart_block->poll.ufds = ufds; |
| 967 | restart_block->poll.nfds = nfds; |
| 968 | |
| 969 | if (timeout_msecs >= 0) { |
| 970 | restart_block->poll.tv_sec = end_time.tv_sec; |
| 971 | restart_block->poll.tv_nsec = end_time.tv_nsec; |
| 972 | restart_block->poll.has_timeout = 1; |
| 973 | } else |
| 974 | restart_block->poll.has_timeout = 0; |
| 975 | |
Chris Wright | 3075d9d | 2007-10-16 23:27:18 -0700 | [diff] [blame] | 976 | ret = -ERESTART_RESTARTBLOCK; |
| 977 | } |
| 978 | return ret; |
David Woodhouse | 9f72949 | 2006-01-18 17:44:05 -0800 | [diff] [blame] | 979 | } |
| 980 | |
Heiko Carstens | d4e8204 | 2009-01-14 14:14:34 +0100 | [diff] [blame] | 981 | SYSCALL_DEFINE5(ppoll, struct pollfd __user *, ufds, unsigned int, nfds, |
| 982 | struct timespec __user *, tsp, const sigset_t __user *, sigmask, |
| 983 | size_t, sigsetsize) |
David Woodhouse | 9f72949 | 2006-01-18 17:44:05 -0800 | [diff] [blame] | 984 | { |
| 985 | sigset_t ksigmask, sigsaved; |
Arjan van de Ven | 8ff3e8e | 2008-08-31 08:26:40 -0700 | [diff] [blame] | 986 | struct timespec ts, end_time, *to = NULL; |
David Woodhouse | 9f72949 | 2006-01-18 17:44:05 -0800 | [diff] [blame] | 987 | int ret; |
| 988 | |
| 989 | if (tsp) { |
| 990 | if (copy_from_user(&ts, tsp, sizeof(ts))) |
| 991 | return -EFAULT; |
| 992 | |
Arjan van de Ven | 8ff3e8e | 2008-08-31 08:26:40 -0700 | [diff] [blame] | 993 | to = &end_time; |
| 994 | if (poll_select_set_timeout(to, ts.tv_sec, ts.tv_nsec)) |
| 995 | return -EINVAL; |
David Woodhouse | 9f72949 | 2006-01-18 17:44:05 -0800 | [diff] [blame] | 996 | } |
| 997 | |
| 998 | if (sigmask) { |
| 999 | /* XXX: Don't preclude handling different sized sigset_t's. */ |
| 1000 | if (sigsetsize != sizeof(sigset_t)) |
| 1001 | return -EINVAL; |
| 1002 | if (copy_from_user(&ksigmask, sigmask, sizeof(ksigmask))) |
| 1003 | return -EFAULT; |
| 1004 | |
| 1005 | sigdelsetmask(&ksigmask, sigmask(SIGKILL)|sigmask(SIGSTOP)); |
| 1006 | sigprocmask(SIG_SETMASK, &ksigmask, &sigsaved); |
| 1007 | } |
| 1008 | |
Arjan van de Ven | 8ff3e8e | 2008-08-31 08:26:40 -0700 | [diff] [blame] | 1009 | ret = do_sys_poll(ufds, nfds, to); |
David Woodhouse | 9f72949 | 2006-01-18 17:44:05 -0800 | [diff] [blame] | 1010 | |
| 1011 | /* We can restart this syscall, usually */ |
| 1012 | if (ret == -EINTR) { |
| 1013 | /* |
| 1014 | * Don't restore the signal mask yet. Let do_signal() deliver |
| 1015 | * the signal on the way back to userspace, before the signal |
| 1016 | * mask is restored. |
| 1017 | */ |
| 1018 | if (sigmask) { |
| 1019 | memcpy(¤t->saved_sigmask, &sigsaved, |
| 1020 | sizeof(sigsaved)); |
Roland McGrath | 4e4c22c | 2008-04-30 00:53:06 -0700 | [diff] [blame] | 1021 | set_restore_sigmask(); |
David Woodhouse | 9f72949 | 2006-01-18 17:44:05 -0800 | [diff] [blame] | 1022 | } |
| 1023 | ret = -ERESTARTNOHAND; |
| 1024 | } else if (sigmask) |
| 1025 | sigprocmask(SIG_SETMASK, &sigsaved, NULL); |
| 1026 | |
Arjan van de Ven | 8ff3e8e | 2008-08-31 08:26:40 -0700 | [diff] [blame] | 1027 | ret = poll_select_copy_remaining(&end_time, tsp, 0, ret); |
David Woodhouse | 9f72949 | 2006-01-18 17:44:05 -0800 | [diff] [blame] | 1028 | |
| 1029 | return ret; |
| 1030 | } |