Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
aio: don't bother with unmapping when aio_free_ring() is coming from exit_aio()
... since exit_mmap() is coming and it will munmap() everything anyway.
In all other cases aio_free_ring() has ctx->mm == current->mm; moreover,
all other callers of vm_munmap() have mm == current->mm, so this will
allow us to get rid of mm argument of vm_munmap().
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
+14
-1
+14
-1
fs/aio.c
+14
-1
fs/aio.c
···
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for (i=0; i<info->nr_pages; i++)
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put_page(info->ring_pages[i]);
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-
if (info->mmap_size)
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+
if (info->mmap_size) {
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BUG_ON(ctx->mm != current->mm);
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vm_munmap(ctx->mm, info->mmap_base, info->mmap_size);
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+
}
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if (info->ring_pages && info->ring_pages != info->internal_pages)
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kfree(info->ring_pages);
···
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"exit_aio:ioctx still alive: %d %d %d\n",
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atomic_read(&ctx->users), ctx->dead,
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ctx->reqs_active);
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+
/*
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* We don't need to bother with munmap() here -
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* exit_mmap(mm) is coming and it'll unmap everything.
392
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* Since aio_free_ring() uses non-zero ->mmap_size
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+
* as indicator that it needs to unmap the area,
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+
* just set it to 0; aio_free_ring() is the only
395
+
* place that uses ->mmap_size, so it's safe.
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+
* That way we get all munmap done to current->mm -
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+
* all other callers have ctx->mm == current->mm.
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+
*/
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+
ctx->ring_info.mmap_size = 0;
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put_ioctx(ctx);
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}
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}