kmem_cache_free(files_cachep, fdt->free_files);
return;
}
- if (fdt->max_fdset <= __FD_SETSIZE && fdt->max_fds <= NR_OPEN_DEFAULT) {
+ if (fdt->max_fdset <= EMBEDDED_FD_SET_SIZE &&
+ fdt->max_fds <= NR_OPEN_DEFAULT) {
/*
* The fdtable was embedded
*/
void free_fdtable(struct fdtable *fdt)
{
- if (fdt->free_files || fdt->max_fdset > __FD_SETSIZE ||
- fdt->max_fds > NR_OPEN_DEFAULT)
+ if (fdt->free_files ||
+ fdt->max_fdset > EMBEDDED_FD_SET_SIZE ||
+ fdt->max_fds > NR_OPEN_DEFAULT)
call_rcu(&fdt->rcu, free_fdtable_rcu);
}
(nfdt->max_fds - fdt->max_fds) *
sizeof(struct file *));
}
- nfdt->next_fd = fdt->next_fd;
}
/*
void free_fdset(fd_set *array, int num)
{
- int size = num / 8;
-
- if (num <= __FD_SETSIZE) /* Don't free an embedded fdset */
+ if (num <= EMBEDDED_FD_SET_SIZE) /* Don't free an embedded fdset */
return;
- else if (size <= PAGE_SIZE)
+ else if (num <= 8 * PAGE_SIZE)
kfree(array);
else
vfree(array);
fd_set *new_openset = NULL, *new_execset = NULL;
struct file **new_fds;
- fdt = kmalloc(sizeof(*fdt), GFP_KERNEL);
+ fdt = kzalloc(sizeof(*fdt), GFP_KERNEL);
if (!fdt)
goto out;
- memset(fdt, 0, sizeof(*fdt));
- nfds = __FD_SETSIZE;
- /* Expand to the max in easy steps */
- do {
- if (nfds < (PAGE_SIZE * 8))
- nfds = PAGE_SIZE * 8;
- else {
- nfds = nfds * 2;
- if (nfds > NR_OPEN)
- nfds = NR_OPEN;
- }
- } while (nfds <= nr);
+ nfds = max_t(int, 8 * L1_CACHE_BYTES, roundup_pow_of_two(nr + 1));
+ if (nfds > NR_OPEN)
+ nfds = NR_OPEN;
new_openset = alloc_fdset(nfds);
new_execset = alloc_fdset(nfds);
} while (nfds <= nr);
new_fds = alloc_fd_array(nfds);
if (!new_fds)
- goto out;
+ goto out2;
fdt->fd = new_fds;
fdt->max_fds = nfds;
fdt->free_files = NULL;
return fdt;
+out2:
+ nfds = fdt->max_fdset;
out:
- if (new_openset)
- free_fdset(new_openset, nfds);
- if (new_execset)
- free_fdset(new_execset, nfds);
+ free_fdset(new_openset, nfds);
+ free_fdset(new_execset, nfds);
kfree(fdt);
return NULL;
}
/*
- * Expands the file descriptor table - it will allocate a new fdtable and
- * both fd array and fdset. It is expected to be called with the
- * files_lock held.
+ * Expand the file descriptor table.
+ * This function will allocate a new fdtable and both fd array and fdset, of
+ * the given size.
+ * Return <0 error code on error; 1 on successful completion.
+ * The files->file_lock should be held on entry, and will be held on exit.
*/
static int expand_fdtable(struct files_struct *files, int nr)
__releases(files->file_lock)
__acquires(files->file_lock)
{
- int error = 0;
- struct fdtable *fdt;
- struct fdtable *nfdt = NULL;
+ struct fdtable *new_fdt, *cur_fdt;
spin_unlock(&files->file_lock);
- nfdt = alloc_fdtable(nr);
- if (!nfdt) {
- error = -ENOMEM;
- spin_lock(&files->file_lock);
- goto out;
- }
-
+ new_fdt = alloc_fdtable(nr);
spin_lock(&files->file_lock);
- fdt = files_fdtable(files);
+ if (!new_fdt)
+ return -ENOMEM;
/*
- * Check again since another task may have expanded the
- * fd table while we dropped the lock
+ * Check again since another task may have expanded the fd table while
+ * we dropped the lock
*/
- if (nr >= fdt->max_fds || nr >= fdt->max_fdset) {
- copy_fdtable(nfdt, fdt);
+ cur_fdt = files_fdtable(files);
+ if (nr >= cur_fdt->max_fds || nr >= cur_fdt->max_fdset) {
+ /* Continue as planned */
+ copy_fdtable(new_fdt, cur_fdt);
+ rcu_assign_pointer(files->fdt, new_fdt);
+ free_fdtable(cur_fdt);
} else {
- /* Somebody expanded while we dropped file_lock */
- spin_unlock(&files->file_lock);
- __free_fdtable(nfdt);
- spin_lock(&files->file_lock);
- goto out;
+ /* Somebody else expanded, so undo our attempt */
+ __free_fdtable(new_fdt);
}
- rcu_assign_pointer(files->fdt, nfdt);
- free_fdtable(fdt);
-out:
- return error;
+ return 1;
}
/*
* Expand files.
- * Return <0 on error; 0 nothing done; 1 files expanded, we may have blocked.
- * Should be called with the files->file_lock spinlock held for write.
+ * This function will expand the file structures, if the requested size exceeds
+ * the current capacity and there is room for expansion.
+ * Return <0 error code on error; 0 when nothing done; 1 when files were
+ * expanded and execution may have blocked.
+ * The files->file_lock should be held on entry, and will be held on exit.
*/
int expand_files(struct files_struct *files, int nr)
{
- int err, expand = 0;
struct fdtable *fdt;
fdt = files_fdtable(files);
- if (nr >= fdt->max_fdset || nr >= fdt->max_fds) {
- if (fdt->max_fdset >= NR_OPEN ||
- fdt->max_fds >= NR_OPEN || nr >= NR_OPEN) {
- err = -EMFILE;
- goto out;
- }
- expand = 1;
- if ((err = expand_fdtable(files, nr)))
- goto out;
- }
- err = expand;
-out:
- return err;
+ /* Do we need to expand? */
+ if (nr < fdt->max_fdset && nr < fdt->max_fds)
+ return 0;
+ /* Can we expand? */
+ if (fdt->max_fdset >= NR_OPEN || fdt->max_fds >= NR_OPEN ||
+ nr >= NR_OPEN)
+ return -EMFILE;
+
+ /* All good, so we try */
+ return expand_fdtable(files, nr);
}
static void __devinit fdtable_defer_list_init(int cpu)
void __init files_defer_init(void)
{
int i;
- for_each_cpu(i)
+ for_each_possible_cpu(i)
fdtable_defer_list_init(i);
}
git.openpandora.org / pandora-kernel.git / blobdiff