X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=fs%2Fselect.c;h=1815a57d225585122c22dd0a357dbdced59e1c40;hb=987b0145d94eecf292d8b301228356f44611ab7c;hp=8cd6dc31fbb657d34fcf40ad4e6376ec90028947;hpb=f7ed79d23a47594e7834d66a8f14449796d4f3e6;p=linux-2.6.git diff --git a/fs/select.c b/fs/select.c index 8cd6dc31f..1815a57d2 100644 --- a/fs/select.c +++ b/fs/select.c @@ -23,13 +23,18 @@ #include #include #include -#include #include #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; @@ -59,24 +64,13 @@ void poll_initwait(struct poll_wqueues *pwq) 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) -{ - if (remove_wait_queue(entry->wait_address,&entry->wait) < 0) - print_symbol("bad poll-entry for %s", (unsigned long) entry->filp->f_op->poll); - 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; @@ -84,7 +78,8 @@ void poll_freewait(struct poll_wqueues *pwq) 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; @@ -94,14 +89,12 @@ void poll_freewait(struct poll_wqueues *pwq) 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; @@ -109,7 +102,7 @@ static struct poll_table_entry *poll_get_entry(poll_table *_p) if (!new_table) { p->error = -ENOMEM; __set_current_state(TASK_RUNNING); - return NULL; + return; } new_table->entry = new_table->entries; new_table->next = table; @@ -117,21 +110,16 @@ static struct poll_table_entry *poll_get_entry(poll_table *_p) 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) @@ -222,7 +210,7 @@ int do_select(int n, fd_set_bits *fds, s64 *timeout) 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++; @@ -233,18 +221,17 @@ int do_select(int n, fd_set_bits *fds, s64 *timeout) } 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++; @@ -297,6 +284,16 @@ int do_select(int n, fd_set_bits *fds, s64 *timeout) 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 @@ -312,12 +309,9 @@ static int core_sys_select(int n, fd_set __user *inp, fd_set __user *outp, 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) @@ -336,21 +330,17 @@ static int core_sys_select(int n, fd_set __user *inp, fd_set __user *outp, * 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)) || @@ -377,8 +367,7 @@ static int core_sys_select(int n, fd_set __user *inp, fd_set __user *outp, ret = -EFAULT; out: - if (bits != stack_fds) - kfree(bits); + select_bits_free(bits, size); out_nofds: return ret; } @@ -562,15 +551,14 @@ static void do_pollfd(unsigned int num, struct pollfd * fdpage, fdp = fdpage+i; fd = fdp->fd; if (fd >= 0) { - int fput_needed; - struct file * file = fget_light(fd, &fput_needed); + 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_light(file, fput_needed); + fput(file); } if (mask) { *pwait = NULL; @@ -631,9 +619,6 @@ static int do_poll(unsigned int nfds, struct poll_list *list, 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; @@ -643,11 +628,6 @@ int do_sys_poll(struct pollfd __user *ufds, unsigned int nfds, s64 *timeout) 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(); @@ -665,23 +645,14 @@ int do_sys_poll(struct pollfd __user *ufds, unsigned int nfds, s64 *timeout) 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 @@ -689,7 +660,7 @@ int do_sys_poll(struct pollfd __user *ufds, unsigned int nfds, s64 *timeout) 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; } @@ -718,8 +689,7 @@ 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);