#define ROUND_UP(x,y) (((x)+(y)-1)/(y))
#define DEFAULT_POLLMASK (POLLIN | POLLOUT | POLLRDNORM | POLLWRNORM)
+struct poll_table_entry {
+ struct file * filp;
+ wait_queue_t wait;
+ wait_queue_head_t * wait_address;
+};
+
struct poll_table_page {
struct poll_table_page * next;
struct poll_table_entry * entry;
init_poll_funcptr(&pwq->pt, __pollwait);
pwq->error = 0;
pwq->table = NULL;
- pwq->inline_index = 0;
}
EXPORT_SYMBOL(poll_initwait);
-static void free_poll_entry(struct poll_table_entry *entry)
-{
- remove_wait_queue(entry->wait_address,&entry->wait);
- fput(entry->filp);
-}
-
void poll_freewait(struct poll_wqueues *pwq)
{
struct poll_table_page * p = pwq->table;
- int i;
- for (i = 0; i < pwq->inline_index; i++)
- free_poll_entry(pwq->inline_entries + i);
while (p) {
struct poll_table_entry * entry;
struct poll_table_page *old;
entry = p->entry;
do {
entry--;
- free_poll_entry(entry);
+ remove_wait_queue(entry->wait_address,&entry->wait);
+ fput(entry->filp);
} while (entry > p->entries);
old = p;
p = p->next;
EXPORT_SYMBOL(poll_freewait);
-static struct poll_table_entry *poll_get_entry(poll_table *_p)
+static void __pollwait(struct file *filp, wait_queue_head_t *wait_address,
+ poll_table *_p)
{
struct poll_wqueues *p = container_of(_p, struct poll_wqueues, pt);
struct poll_table_page *table = p->table;
- if (p->inline_index < N_INLINE_POLL_ENTRIES)
- return p->inline_entries + p->inline_index++;
-
if (!table || POLL_TABLE_FULL(table)) {
struct poll_table_page *new_table;
if (!new_table) {
p->error = -ENOMEM;
__set_current_state(TASK_RUNNING);
- return NULL;
+ return;
}
new_table->entry = new_table->entries;
new_table->next = table;
table = new_table;
}
- return table->entry++;
-}
-
-/* Add a new entry */
-static void __pollwait(struct file *filp, wait_queue_head_t *wait_address,
- poll_table *p)
-{
- struct poll_table_entry *entry = poll_get_entry(p);
- if (!entry)
- return;
- get_file(filp);
- entry->filp = filp;
- entry->wait_address = wait_address;
- init_waitqueue_entry(&entry->wait, current);
- add_wait_queue(wait_address,&entry->wait);
+ /* Add a new entry */
+ {
+ struct poll_table_entry * entry = table->entry;
+ table->entry = entry+1;
+ get_file(filp);
+ entry->filp = filp;
+ entry->wait_address = wait_address;
+ init_waitqueue_entry(&entry->wait, current);
+ add_wait_queue(wait_address,&entry->wait);
+ }
}
#define FDS_IN(fds, n) (fds->in + n)
for (i = 0; i < n; ++rinp, ++routp, ++rexp) {
unsigned long in, out, ex, all_bits, bit = 1, mask, j;
unsigned long res_in = 0, res_out = 0, res_ex = 0;
- const struct file_operations *f_op = NULL;
+ struct file_operations *f_op = NULL;
struct file *file = NULL;
in = *inp++; out = *outp++; ex = *exp++;
}
for (j = 0; j < __NFDBITS; ++j, ++i, bit <<= 1) {
- int fput_needed;
if (i >= n)
break;
if (!(bit & all_bits))
continue;
- file = fget_light(i, &fput_needed);
+ file = fget(i);
if (file) {
f_op = file->f_op;
mask = DEFAULT_POLLMASK;
if (f_op && f_op->poll)
mask = (*f_op->poll)(file, retval ? NULL : wait);
- fput_light(file, fput_needed);
+ fput(file);
if ((mask & POLLIN_SET) && (in & bit)) {
res_in |= bit;
retval++;
return retval;
}
+static void *select_bits_alloc(int size)
+{
+ return kmalloc(6 * size, GFP_KERNEL);
+}
+
+static void select_bits_free(void *bits, int size)
+{
+ kfree(bits);
+}
+
/*
* We can actually return ERESTARTSYS instead of EINTR, but I'd
* like to be certain this leads to no problems. So I return
fd_set __user *exp, s64 *timeout)
{
fd_set_bits fds;
- void *bits;
- int ret, max_fdset;
- unsigned int size;
+ char *bits;
+ int ret, size, max_fdset;
struct fdtable *fdt;
- /* Allocate small arguments on the stack to save memory and be faster */
- long stack_fds[SELECT_STACK_ALLOC/sizeof(long)];
ret = -EINVAL;
if (n < 0)
* since we used fdset we need to allocate memory in units of
* long-words.
*/
+ ret = -ENOMEM;
size = FDS_BYTES(n);
- bits = stack_fds;
- if (size > sizeof(stack_fds) / 6) {
- /* Not enough space in on-stack array; must use kmalloc */
- ret = -ENOMEM;
- bits = kmalloc(6 * size, GFP_KERNEL);
- if (!bits)
- goto out_nofds;
- }
- fds.in = bits;
- fds.out = bits + size;
- fds.ex = bits + 2*size;
- fds.res_in = bits + 3*size;
- fds.res_out = bits + 4*size;
- fds.res_ex = bits + 5*size;
+ bits = select_bits_alloc(size);
+ if (!bits)
+ goto out_nofds;
+ fds.in = (unsigned long *) bits;
+ fds.out = (unsigned long *) (bits + size);
+ fds.ex = (unsigned long *) (bits + 2*size);
+ fds.res_in = (unsigned long *) (bits + 3*size);
+ fds.res_out = (unsigned long *) (bits + 4*size);
+ fds.res_ex = (unsigned long *) (bits + 5*size);
if ((ret = get_fd_set(n, inp, fds.in)) ||
(ret = get_fd_set(n, outp, fds.out)) ||
ret = -EFAULT;
out:
- if (bits != stack_fds)
- kfree(bits);
+ select_bits_free(bits, size);
out_nofds:
return ret;
}
#define POLLFD_PER_PAGE ((PAGE_SIZE-sizeof(struct poll_list)) / sizeof(struct pollfd))
-/*
- * Fish for pollable events on the pollfd->fd file descriptor. We're only
- * interested in events matching the pollfd->events mask, and the result
- * matching that mask is both recorded in pollfd->revents and returned. The
- * pwait poll_table will be used by the fd-provided poll handler for waiting,
- * if non-NULL.
- */
-static inline unsigned int do_pollfd(struct pollfd *pollfd, poll_table *pwait)
+static void do_pollfd(unsigned int num, struct pollfd * fdpage,
+ poll_table ** pwait, int *count)
{
- unsigned int mask;
- int fd;
-
- mask = 0;
- fd = pollfd->fd;
- if (fd >= 0) {
- int fput_needed;
- struct file * file;
-
- file = fget_light(fd, &fput_needed);
- mask = POLLNVAL;
- if (file != NULL) {
- mask = DEFAULT_POLLMASK;
- if (file->f_op && file->f_op->poll)
- mask = file->f_op->poll(file, pwait);
- /* Mask out unneeded events. */
- mask &= pollfd->events | POLLERR | POLLHUP;
- fput_light(file, fput_needed);
+ int i;
+
+ for (i = 0; i < num; i++) {
+ int fd;
+ unsigned int mask;
+ struct pollfd *fdp;
+
+ mask = 0;
+ fdp = fdpage+i;
+ fd = fdp->fd;
+ if (fd >= 0) {
+ struct file * file = fget(fd);
+ mask = POLLNVAL;
+ if (file != NULL) {
+ mask = DEFAULT_POLLMASK;
+ if (file->f_op && file->f_op->poll)
+ mask = file->f_op->poll(file, *pwait);
+ mask &= fdp->events | POLLERR | POLLHUP;
+ fput(file);
+ }
+ if (mask) {
+ *pwait = NULL;
+ (*count)++;
+ }
}
+ fdp->revents = mask;
}
- pollfd->revents = mask;
-
- return mask;
}
static int do_poll(unsigned int nfds, struct poll_list *list,
long __timeout;
set_current_state(TASK_INTERRUPTIBLE);
- for (walk = list; walk != NULL; walk = walk->next) {
- struct pollfd * pfd, * pfd_end;
-
- pfd = walk->entries;
- pfd_end = pfd + walk->len;
- for (; pfd != pfd_end; pfd++) {
- /*
- * Fish for events. If we found one, record it
- * and kill the poll_table, so we don't
- * needlessly register any other waiters after
- * this. They'll get immediately deregistered
- * when we break out and return.
- */
- if (do_pollfd(pfd, pt)) {
- count++;
- pt = NULL;
- }
- }
+ walk = list;
+ while(walk != NULL) {
+ do_pollfd( walk->len, walk->entries, &pt, &count);
+ walk = walk->next;
}
- /*
- * All waiters have already been registered, so don't provide
- * a poll_table to them on the next loop iteration.
- */
pt = NULL;
if (count || !*timeout || signal_pending(current))
break;
return count;
}
-#define N_STACK_PPS ((sizeof(stack_pps) - sizeof(struct poll_list)) / \
- sizeof(struct pollfd))
-
int do_sys_poll(struct pollfd __user *ufds, unsigned int nfds, s64 *timeout)
{
struct poll_wqueues table;
struct poll_list *walk;
struct fdtable *fdt;
int max_fdset;
- /* 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;
/* Do a sanity check on nfds ... */
rcu_read_lock();
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 = kmalloc(sizeof(struct poll_list)+
+ sizeof(struct pollfd)*
+ (i>POLLFD_PER_PAGE?POLLFD_PER_PAGE:i),
+ GFP_KERNEL);
+ if(pp==NULL)
+ goto out_fds;
pp->next=NULL;
- pp->len = num;
+ pp->len = (i>POLLFD_PER_PAGE?POLLFD_PER_PAGE:i);
if (head == NULL)
head = pp;
else
walk = pp;
if (copy_from_user(pp->entries, ufds + nfds-i,
- sizeof(struct pollfd)*num)) {
+ sizeof(struct pollfd)*pp->len)) {
err = -EFAULT;
goto out_fds;
}
walk = head;
while(walk!=NULL) {
struct poll_list *pp = walk->next;
- if (walk != stack_pp)
- kfree(walk);
+ kfree(walk);
walk = pp;
}
poll_freewait(&table);
asmlinkage long sys_poll(struct pollfd __user *ufds, unsigned int nfds,
long timeout_msecs)
{
- s64 timeout_jiffies;
+ s64 timeout_jiffies = 0;
- if (timeout_msecs > 0) {
+ if (timeout_msecs) {
#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);
git://git.onelab.eu / linux-2.6.git / blobdiff