From 1e240e8d4a7d92232b6214e02a0a4197a53afd6c Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Wed, 26 Jun 2019 14:27:08 +0200 Subject: memremap: move dev_pagemap callbacks into a separate structure The dev_pagemap is a growing too many callbacks. Move them into a separate ops structure so that they are not duplicated for multiple instances, and an attacker can't easily overwrite them. Signed-off-by: Christoph Hellwig Reviewed-by: Logan Gunthorpe Reviewed-by: Jason Gunthorpe Reviewed-by: Dan Williams Tested-by: Dan Williams Signed-off-by: Jason Gunthorpe --- drivers/nvdimm/pmem.c | 19 +++++++++++-------- 1 file changed, 11 insertions(+), 8 deletions(-) (limited to 'drivers/nvdimm') diff --git a/drivers/nvdimm/pmem.c b/drivers/nvdimm/pmem.c index 24d7fe7c74ed..c2449af2b388 100644 --- a/drivers/nvdimm/pmem.c +++ b/drivers/nvdimm/pmem.c @@ -303,7 +303,7 @@ static const struct attribute_group *pmem_attribute_groups[] = { NULL, }; -static void __pmem_release_queue(struct percpu_ref *ref) +static void pmem_pagemap_cleanup(struct percpu_ref *ref) { struct request_queue *q; @@ -313,10 +313,10 @@ static void __pmem_release_queue(struct percpu_ref *ref) static void pmem_release_queue(void *ref) { - __pmem_release_queue(ref); + pmem_pagemap_cleanup(ref); } -static void pmem_freeze_queue(struct percpu_ref *ref) +static void pmem_pagemap_kill(struct percpu_ref *ref) { struct request_queue *q; @@ -339,19 +339,24 @@ static void pmem_release_pgmap_ops(void *__pgmap) dev_pagemap_put_ops(); } -static void fsdax_pagefree(struct page *page, void *data) +static void pmem_pagemap_page_free(struct page *page, void *data) { wake_up_var(&page->_refcount); } +static const struct dev_pagemap_ops fsdax_pagemap_ops = { + .page_free = pmem_pagemap_page_free, + .kill = pmem_pagemap_kill, + .cleanup = pmem_pagemap_cleanup, +}; + static int setup_pagemap_fsdax(struct device *dev, struct dev_pagemap *pgmap) { dev_pagemap_get_ops(); if (devm_add_action_or_reset(dev, pmem_release_pgmap_ops, pgmap)) return -ENOMEM; pgmap->type = MEMORY_DEVICE_FS_DAX; - pgmap->page_free = fsdax_pagefree; - + pgmap->ops = &fsdax_pagemap_ops; return 0; } @@ -409,8 +414,6 @@ static int pmem_attach_disk(struct device *dev, pmem->pfn_flags = PFN_DEV; pmem->pgmap.ref = &q->q_usage_counter; - pmem->pgmap.kill = pmem_freeze_queue; - pmem->pgmap.cleanup = __pmem_release_queue; if (is_nd_pfn(dev)) { if (setup_pagemap_fsdax(dev, &pmem->pgmap)) return -ENOMEM; -- cgit v1.2.3-59-g8ed1b