* of fds to overcome nfds < 16390 descriptors limit (Tigran Aivazian).
*/
+#include <linux/kernel.h>
#include <linux/syscalls.h>
#include <linux/module.h>
#include <linux/slab.h>
-#include <linux/smp_lock.h>
#include <linux/poll.h>
#include <linux/personality.h> /* for STICKY_TIMEOUTS */
#include <linux/file.h>
#include <asm/uaccess.h>
-#define ROUND_UP(x,y) (((x)+(y)-1)/(y))
-#define DEFAULT_POLLMASK (POLLIN | POLLOUT | POLLRDNORM | POLLWRNORM)
-
struct poll_table_page {
struct poll_table_page * next;
struct poll_table_entry * entry;
static void free_poll_entry(struct poll_table_entry *entry)
{
- remove_wait_queue(entry->wait_address,&entry->wait);
+ remove_wait_queue(entry->wait_address, &entry->wait);
fput(entry->filp);
}
entry->filp = filp;
entry->wait_address = wait_address;
init_waitqueue_entry(&entry->wait, current);
- add_wait_queue(wait_address,&entry->wait);
+ add_wait_queue(wait_address, &entry->wait);
}
#define FDS_IN(fds, n) (fds->in + n)
{
fd_set_bits fds;
void *bits;
- int ret, max_fdset;
+ int ret, max_fds;
unsigned int size;
struct fdtable *fdt;
/* Allocate small arguments on the stack to save memory and be faster */
if (n < 0)
goto out_nofds;
- /* max_fdset can increase, so grab it once to avoid race */
+ /* max_fds can increase, so grab it once to avoid race */
rcu_read_lock();
fdt = files_fdtable(current->files);
- max_fdset = fdt->max_fdset;
+ max_fds = fdt->max_fds;
rcu_read_unlock();
- if (n > max_fdset)
- n = max_fdset;
+ if (n > max_fds)
+ n = max_fds;
/*
* We need 6 bitmaps (in/out/ex for both incoming and outgoing),
if ((u64)tv.tv_sec >= (u64)MAX_INT64_SECONDS)
timeout = -1; /* infinite */
else {
- timeout = ROUND_UP(tv.tv_usec, USEC_PER_SEC/HZ);
+ timeout = DIV_ROUND_UP(tv.tv_usec, USEC_PER_SEC/HZ);
timeout += tv.tv_sec * HZ;
}
}
if ((u64)ts.tv_sec >= (u64)MAX_INT64_SECONDS)
timeout = -1; /* infinite */
else {
- timeout = ROUND_UP(ts.tv_nsec, NSEC_PER_SEC/HZ);
+ timeout = DIV_ROUND_UP(ts.tv_nsec, NSEC_PER_SEC/HZ);
timeout += ts.tv_sec * HZ;
}
}
/* Optimise the no-wait case */
if (!(*timeout))
pt = NULL;
-
+
for (;;) {
struct poll_list *walk;
long __timeout;
* a poll_table to them on the next loop iteration.
*/
pt = NULL;
- if (count || !*timeout || signal_pending(current))
- break;
- count = wait->error;
- if (count)
+ if (!count) {
+ count = wait->error;
+ if (signal_pending(current))
+ count = -EINTR;
+ }
+ if (count || !*timeout)
break;
if (*timeout < 0) {
int do_sys_poll(struct pollfd __user *ufds, unsigned int nfds, s64 *timeout)
{
struct poll_wqueues table;
- int fdcount, err;
- unsigned int i;
- struct poll_list *head;
- struct poll_list *walk;
- struct fdtable *fdt;
- int max_fdset;
+ int err = -EFAULT, fdcount, len, size;
/* Allocate small arguments on the stack to save memory and be
faster - use long to make sure the buffer is aligned properly
on 64 bit archs to avoid unaligned access */
long stack_pps[POLL_STACK_ALLOC/sizeof(long)];
- struct poll_list *stack_pp = NULL;
+ struct poll_list *const head = (struct poll_list *)stack_pps;
+ struct poll_list *walk = head;
+ unsigned long todo = nfds;
- /* Do a sanity check on nfds ... */
- rcu_read_lock();
- fdt = files_fdtable(current->files);
- max_fdset = fdt->max_fdset;
- rcu_read_unlock();
- if (nfds > max_fdset && nfds > OPEN_MAX)
+ if (nfds > current->signal->rlim[RLIMIT_NOFILE].rlim_cur)
return -EINVAL;
- poll_initwait(&table);
+ len = min_t(unsigned int, nfds, N_STACK_PPS);
+ for (;;) {
+ walk->next = NULL;
+ walk->len = len;
+ if (!len)
+ break;
- head = NULL;
- walk = NULL;
- i = nfds;
- err = -ENOMEM;
- while(i!=0) {
- struct poll_list *pp;
- int num, size;
- if (stack_pp == NULL)
- num = N_STACK_PPS;
- else
- num = POLLFD_PER_PAGE;
- if (num > i)
- num = i;
- size = sizeof(struct poll_list) + sizeof(struct pollfd)*num;
- if (!stack_pp)
- stack_pp = pp = (struct poll_list *)stack_pps;
- else {
- pp = kmalloc(size, GFP_KERNEL);
- if (!pp)
- goto out_fds;
- }
- pp->next=NULL;
- pp->len = num;
- if (head == NULL)
- head = pp;
- else
- walk->next = pp;
+ if (copy_from_user(walk->entries, ufds + nfds-todo,
+ sizeof(struct pollfd) * walk->len))
+ goto out_fds;
- walk = pp;
- if (copy_from_user(pp->entries, ufds + nfds-i,
- sizeof(struct pollfd)*num)) {
- err = -EFAULT;
+ todo -= walk->len;
+ if (!todo)
+ break;
+
+ len = min(todo, POLLFD_PER_PAGE);
+ size = sizeof(struct poll_list) + sizeof(struct pollfd) * len;
+ walk = walk->next = kmalloc(size, GFP_KERNEL);
+ if (!walk) {
+ err = -ENOMEM;
goto out_fds;
}
- i -= pp->len;
}
+ poll_initwait(&table);
fdcount = do_poll(nfds, head, &table, timeout);
+ poll_freewait(&table);
- /* OK, now copy the revents fields back to user space. */
- walk = head;
- err = -EFAULT;
- while(walk != NULL) {
+ for (walk = head; walk; walk = walk->next) {
struct pollfd *fds = walk->entries;
int j;
- for (j=0; j < walk->len; j++, ufds++) {
- if(__put_user(fds[j].revents, &ufds->revents))
+ for (j = 0; j < walk->len; j++, ufds++)
+ if (__put_user(fds[j].revents, &ufds->revents))
goto out_fds;
- }
- walk = walk->next;
}
+
err = fdcount;
- if (!fdcount && signal_pending(current))
- err = -EINTR;
out_fds:
- walk = head;
- while(walk!=NULL) {
- struct poll_list *pp = walk->next;
- if (walk != stack_pp)
- kfree(walk);
- walk = pp;
+ walk = head->next;
+ while (walk) {
+ struct poll_list *pos = walk;
+ walk = walk->next;
+ kfree(pos);
}
- poll_freewait(&table);
+
return err;
}
+static long do_restart_poll(struct restart_block *restart_block)
+{
+ struct pollfd __user *ufds = (struct pollfd __user*)restart_block->arg0;
+ int nfds = restart_block->arg1;
+ s64 timeout = ((s64)restart_block->arg3<<32) | (s64)restart_block->arg2;
+ int ret;
+
+ ret = do_sys_poll(ufds, nfds, &timeout);
+ if (ret == -EINTR) {
+ restart_block->fn = do_restart_poll;
+ restart_block->arg2 = timeout & 0xFFFFFFFF;
+ restart_block->arg3 = (u64)timeout >> 32;
+ ret = -ERESTART_RESTARTBLOCK;
+ }
+ return ret;
+}
+
asmlinkage long sys_poll(struct pollfd __user *ufds, unsigned int nfds,
long timeout_msecs)
{
- s64 timeout_jiffies = 0;
+ s64 timeout_jiffies;
+ int ret;
- if (timeout_msecs) {
+ if (timeout_msecs > 0) {
#if HZ > 1000
/* We can only overflow if HZ > 1000 */
if (timeout_msecs / 1000 > (s64)0x7fffffffffffffffULL / (s64)HZ)
else
#endif
timeout_jiffies = msecs_to_jiffies(timeout_msecs);
+ } else {
+ /* Infinite (< 0) or no (0) timeout */
+ timeout_jiffies = timeout_msecs;
}
- return do_sys_poll(ufds, nfds, &timeout_jiffies);
+ ret = do_sys_poll(ufds, nfds, &timeout_jiffies);
+ if (ret == -EINTR) {
+ struct restart_block *restart_block;
+ restart_block = ¤t_thread_info()->restart_block;
+ restart_block->fn = do_restart_poll;
+ restart_block->arg0 = (unsigned long)ufds;
+ restart_block->arg1 = nfds;
+ restart_block->arg2 = timeout_jiffies & 0xFFFFFFFF;
+ restart_block->arg3 = (u64)timeout_jiffies >> 32;
+ ret = -ERESTART_RESTARTBLOCK;
+ }
+ return ret;
}
#ifdef TIF_RESTORE_SIGMASK
if ((u64)ts.tv_sec >= (u64)MAX_INT64_SECONDS)
timeout = -1; /* infinite */
else {
- timeout = ROUND_UP(ts.tv_nsec, NSEC_PER_SEC/HZ);
+ timeout = DIV_ROUND_UP(ts.tv_nsec, NSEC_PER_SEC/HZ);
timeout += ts.tv_sec * HZ;
}
}