diff options
Diffstat (limited to 'fs/aio.c')
| -rw-r--r-- | fs/aio.c | 38 |
1 files changed, 18 insertions, 20 deletions
@@ -39,6 +39,8 @@ #include <asm/kmap_types.h> #include <asm/uaccess.h> +#include "internal.h" + #define AIO_RING_MAGIC 0xa10a10a1 #define AIO_RING_COMPAT_FEATURES 1 #define AIO_RING_INCOMPAT_FEATURES 0 @@ -141,9 +143,6 @@ static void aio_free_ring(struct kioctx *ctx) for (i = 0; i < ctx->nr_pages; i++) put_page(ctx->ring_pages[i]); - if (ctx->mmap_size) - vm_munmap(ctx->mmap_base, ctx->mmap_size); - if (ctx->ring_pages && ctx->ring_pages != ctx->internal_pages) kfree(ctx->ring_pages); } @@ -322,11 +321,6 @@ static void free_ioctx(struct kioctx *ctx) aio_free_ring(ctx); - spin_lock(&aio_nr_lock); - BUG_ON(aio_nr - ctx->max_reqs > aio_nr); - aio_nr -= ctx->max_reqs; - spin_unlock(&aio_nr_lock); - pr_debug("freeing %p\n", ctx); /* @@ -435,17 +429,24 @@ static void kill_ioctx(struct kioctx *ctx) { if (!atomic_xchg(&ctx->dead, 1)) { hlist_del_rcu(&ctx->list); - /* Between hlist_del_rcu() and dropping the initial ref */ - synchronize_rcu(); /* - * We can't punt to workqueue here because put_ioctx() -> - * free_ioctx() will unmap the ringbuffer, and that has to be - * done in the original process's context. kill_ioctx_rcu/work() - * exist for exit_aio(), as in that path free_ioctx() won't do - * the unmap. + * It'd be more correct to do this in free_ioctx(), after all + * the outstanding kiocbs have finished - but by then io_destroy + * has already returned, so io_setup() could potentially return + * -EAGAIN with no ioctxs actually in use (as far as userspace + * could tell). */ - kill_ioctx_work(&ctx->rcu_work); + spin_lock(&aio_nr_lock); + BUG_ON(aio_nr - ctx->max_reqs > aio_nr); + aio_nr -= ctx->max_reqs; + spin_unlock(&aio_nr_lock); + + if (ctx->mmap_size) + vm_munmap(ctx->mmap_base, ctx->mmap_size); + + /* Between hlist_del_rcu() and dropping the initial ref */ + call_rcu(&ctx->rcu_head, kill_ioctx_rcu); } } @@ -495,10 +496,7 @@ void exit_aio(struct mm_struct *mm) */ ctx->mmap_size = 0; - if (!atomic_xchg(&ctx->dead, 1)) { - hlist_del_rcu(&ctx->list); - call_rcu(&ctx->rcu_head, kill_ioctx_rcu); - } + kill_ioctx(ctx); } } |