diff options
Diffstat (limited to 'fs/select.c')
| -rw-r--r-- | fs/select.c | 32 |
1 files changed, 22 insertions, 10 deletions
diff --git a/fs/select.c b/fs/select.c index a5c213930..0b3718309 100644 --- a/fs/select.c +++ b/fs/select.c @@ -24,6 +24,21 @@ #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; + struct poll_table_entry entries[0]; +}; + +#define POLL_TABLE_FULL(table) \ + ((unsigned long)(table->entry+1) > PAGE_SIZE + (unsigned long)(table)) + /* * Ok, Peter made a complicated, but straightforward multiple_wait() function. * I have rewritten this, taking some shortcuts: This code may not be easy to @@ -44,13 +59,12 @@ void poll_freewait(poll_table* pt) struct poll_table_entry * entry; struct poll_table_page *old; - entry = p->entry + p->nr; - while (p->nr > 0) { - p->nr--; + entry = p->entry; + do { entry--; remove_wait_queue(entry->wait_address,&entry->wait); fput(entry->filp); - } + } while (entry > p->entries); old = p; p = p->next; free_page((unsigned long) old); @@ -61,7 +75,7 @@ void __pollwait(struct file * filp, wait_queue_head_t * wait_address, poll_table { struct poll_table_page *table = p->table; - if (!table || table->nr >= __MAX_POLL_TABLE_ENTRIES) { + if (!table || POLL_TABLE_FULL(table)) { struct poll_table_page *new_table; new_table = (struct poll_table_page *) __get_free_page(GFP_KERNEL); @@ -70,8 +84,7 @@ void __pollwait(struct file * filp, wait_queue_head_t * wait_address, poll_table __set_current_state(TASK_RUNNING); return; } - new_table->nr = 0; - new_table->entry = (struct poll_table_entry *)(new_table + 1); + new_table->entry = new_table->entries; new_table->next = table; p->table = new_table; table = new_table; @@ -79,9 +92,8 @@ void __pollwait(struct file * filp, wait_queue_head_t * wait_address, poll_table /* Add a new entry */ { - struct poll_table_entry * entry; - entry = table->entry + table->nr; - table->nr++; + struct poll_table_entry * entry = table->entry; + table->entry = entry+1; get_file(filp); entry->filp = filp; entry->wait_address = wait_address; |