diff options
| author | Alexey Kardashevskiy | 2021-02-16 14:33:06 +1100 |
|---|---|---|
| committer | Michael Ellerman | 2021-04-23 01:38:04 +1000 |
| commit | 7f1fa82d79947dfabb4046e1d787da9db2bc1c20 (patch) | |
| tree | c5b4c0c664a80359ec39102d2efdab3b6ca581bc /arch | |
| parent | 0db11461677aa5105b9ebbd939aee0ceb77a988b (diff) | |
powerpc/iommu: Allocate it_map by vmalloc
The IOMMU table uses the it_map bitmap to keep track of allocated DMA
pages. This has always been a contiguous array allocated at either
the boot time or when a passed through device is returned to the host OS.
The it_map memory is allocated by alloc_pages() which allocates
contiguous physical memory.
Such allocation method occasionally creates a problem when there is
no big chunk of memory available (no free memory or too fragmented).
On powernv/ioda2 the default DMA window requires 16MB for it_map.
This replaces alloc_pages_node() with vzalloc_node() which allocates
contiguous block but in virtual memory. This should reduce changes of
failure but should not cause other behavioral changes as it_map is only
used by the kernel's DMA hooks/api when MMU is on.
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210216033307.69863-2-aik@ozlabs.ru
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/powerpc/kernel/iommu.c | 15 |
1 files changed, 3 insertions, 12 deletions
diff --git a/arch/powerpc/kernel/iommu.c b/arch/powerpc/kernel/iommu.c index 216871414434..91d0ba7559a6 100644 --- a/arch/powerpc/kernel/iommu.c +++ b/arch/powerpc/kernel/iommu.c @@ -718,7 +718,6 @@ struct iommu_table *iommu_init_table(struct iommu_table *tbl, int nid, { unsigned long sz; static int welcomed = 0; - struct page *page; unsigned int i; struct iommu_pool *p; @@ -727,11 +726,9 @@ struct iommu_table *iommu_init_table(struct iommu_table *tbl, int nid, /* number of bytes needed for the bitmap */ sz = BITS_TO_LONGS(tbl->it_size) * sizeof(unsigned long); - page = alloc_pages_node(nid, GFP_KERNEL, get_order(sz)); - if (!page) + tbl->it_map = vzalloc_node(sz, nid); + if (!tbl->it_map) panic("iommu_init_table: Can't allocate %ld bytes\n", sz); - tbl->it_map = page_address(page); - memset(tbl->it_map, 0, sz); iommu_table_reserve_pages(tbl, res_start, res_end); @@ -773,8 +770,6 @@ struct iommu_table *iommu_init_table(struct iommu_table *tbl, int nid, static void iommu_table_free(struct kref *kref) { - unsigned long bitmap_sz; - unsigned int order; struct iommu_table *tbl; tbl = container_of(kref, struct iommu_table, it_kref); @@ -795,12 +790,8 @@ static void iommu_table_free(struct kref *kref) if (!bitmap_empty(tbl->it_map, tbl->it_size)) pr_warn("%s: Unexpected TCEs\n", __func__); - /* calculate bitmap size in bytes */ - bitmap_sz = BITS_TO_LONGS(tbl->it_size) * sizeof(unsigned long); - /* free bitmap */ - order = get_order(bitmap_sz); - free_pages((unsigned long) tbl->it_map, order); + vfree(tbl->it_map); /* free table */ kfree(tbl); |