mm/cma: don't treat bad input arguments for cma_alloc() as its failure

Invalid cma_alloc() input scenarios - including excess allocation request
should neither be counted as CMA_ALLOC_FAIL nor 'cma->nr_pages_failed' be
updated when applicable with CONFIG_CMA_SYSFS. This also drops 'out' jump
label which has become redundant.

Link: https://lkml.kernel.org/r/20240201023714.3871061-1-anshuman.khandual@arm.com
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Kalesh Singh <kaleshsingh@google.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

diff --git a/mm/cma.c b/mm/cma.c
index e12cf41..b672093 100644 (file)
--- a/mm/cma.c
+++ b/mm/cma.c
@@ -441,13 +441,13 @@ struct page *cma_alloc(struct cma *cma, unsigned long count,
        trace_cma_alloc_start(name, count, align);
 
        if (!cma || !cma->count || !cma->bitmap)
-               goto out;
+               return page;
 
        pr_debug("%s(cma %p, name: %s, count %lu, align %d)\n", __func__,
                (void *)cma, cma->name, count, align);
 
        if (!count)
-               goto out;
+               return page;
 
        mask = cma_bitmap_aligned_mask(cma, align);
        offset = cma_bitmap_aligned_offset(cma, align);
@@ -455,7 +455,7 @@ struct page *cma_alloc(struct cma *cma, unsigned long count,
        bitmap_count = cma_bitmap_pages_to_bits(cma, count);
 
        if (bitmap_count > bitmap_maxno)
-               goto out;
+               return page;
 
        for (;;) {
                spin_lock_irq(&cma->lock);
@@ -514,15 +514,13 @@ struct page *cma_alloc(struct cma *cma, unsigned long count,
        }
 
        pr_debug("%s(): returned %p\n", __func__, page);
-out:
        trace_cma_alloc_finish(name, pfn, page, count, align, ret);
        if (page) {
                count_vm_event(CMA_ALLOC_SUCCESS);
                cma_sysfs_account_success_pages(cma, count);
        } else {
                count_vm_event(CMA_ALLOC_FAIL);
-               if (cma)
-                       cma_sysfs_account_fail_pages(cma, count);
+               cma_sysfs_account_fail_pages(cma, count);
        }
 
        return page;