The patch titled Subject: mm: cma: release trigger has been added to the -mm tree. Its filename is mm-cma-release-trigger.patch This patch should soon appear at http://ozlabs.org/~akpm/mmots/broken-out/mm-cma-release-trigger.patch and later at http://ozlabs.org/~akpm/mmotm/broken-out/mm-cma-release-trigger.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/SubmitChecklist when testing your code *** The -mm tree is included into linux-next and is updated there every 3-4 working days ------------------------------------------------------ From: Sasha Levin <sasha.levin@xxxxxxxxxx> Subject: mm: cma: release trigger Provides a userspace interface to trigger a CMA release. Usage: echo [pages] > free This would provide testing/fuzzing access to the CMA release paths. Signed-off-by: Sasha Levin <sasha.levin@xxxxxxxxxx> Acked-by: Joonsoo Kim <iamjoonsoo.kim@xxxxxxx> Cc: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx> Cc: Laura Abbott <lauraa@xxxxxxxxxxxxxx> Cc: Konrad Rzeszutek Wilk <konrad.wilk@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/cma_debug.c | 57 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 57 insertions(+) diff -puN mm/cma_debug.c~mm-cma-release-trigger mm/cma_debug.c --- a/mm/cma_debug.c~mm-cma-release-trigger +++ a/mm/cma_debug.c @@ -39,6 +39,60 @@ static void cma_add_to_cma_mem_list(stru spin_unlock(&cma->mem_head_lock); } +static struct cma_mem *cma_get_entry_from_list(struct cma *cma) +{ + struct cma_mem *mem = NULL; + + spin_lock(&cma->mem_head_lock); + if (!hlist_empty(&cma->mem_head)) { + mem = hlist_entry(cma->mem_head.first, struct cma_mem, node); + hlist_del_init(&mem->node); + } + spin_unlock(&cma->mem_head_lock); + + return mem; +} + +static int cma_free_mem(struct cma *cma, int count) +{ + struct cma_mem *mem = NULL; + + while (count) { + mem = cma_get_entry_from_list(cma); + if (mem == NULL) + return 0; + + if (mem->n <= count) { + cma_release(cma, mem->p, mem->n); + count -= mem->n; + kfree(mem); + } else if (cma->order_per_bit == 0) { + cma_release(cma, mem->p, count); + mem->p += count; + mem->n -= count; + count = 0; + cma_add_to_cma_mem_list(cma, mem); + } else { + pr_debug("cma: cannot release partial block when order_per_bit != 0\n"); + cma_add_to_cma_mem_list(cma, mem); + break; + } + } + + return 0; + +} + +static int cma_free_write(void *data, u64 val) +{ + int pages = val; + struct cma *cma = data; + + return cma_free_mem(cma, pages); +} + +DEFINE_SIMPLE_ATTRIBUTE(cma_free_fops, NULL, cma_free_write, "%llu\n"); + static int cma_alloc_mem(struct cma *cma, int count) { struct cma_mem *mem; @@ -85,6 +139,9 @@ static void cma_debugfs_add_one(struct c debugfs_create_file("alloc", S_IWUSR, cma_debugfs_root, cma, &cma_alloc_fops); + debugfs_create_file("free", S_IWUSR, cma_debugfs_root, cma, + &cma_free_fops); + debugfs_create_file("base_pfn", S_IRUGO, tmp, &cma->base_pfn, &cma_debugfs_fops); debugfs_create_file("count", S_IRUGO, tmp, _ Patches currently in -mm which might be from sasha.levin@xxxxxxxxxx are origin.patch mm-cma-debugfs-interface.patch mm-cma-allocation-trigger.patch mm-cma-release-trigger.patch mm-cma-allocation-trigger-fix.patch linux-next.patch do_shared_fault-check-that-mmap_sem-is-held.patch -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html