swiotlb: Convert swiotlb_force from int to enum

Convert the flag swiotlb_force from an int to an enum, to prepare for
the advent of more possible values.

Suggested-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>

diff --git a/arch/arm64/mm/dma-mapping.c b/arch/arm64/mm/dma-mapping.c
index 3f74d0d98de63322b15b387cb967009db17079ff..02265a589ef50d52fac7e7b43f436cefd4ecfd6d 100644 (file)
--- a/arch/arm64/mm/dma-mapping.c
+++ b/arch/arm64/mm/dma-mapping.c
@@ -524,7 +524,8 @@ EXPORT_SYMBOL(dummy_dma_ops);
 
 static int __init arm64_dma_init(void)
 {
-       if (swiotlb_force || max_pfn > (arm64_dma_phys_limit >> PAGE_SHIFT))
+       if (swiotlb_force == SWIOTLB_FORCE ||
+           max_pfn > (arm64_dma_phys_limit >> PAGE_SHIFT))
                swiotlb = 1;
 
        return atomic_pool_init();

diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c
index 212c4d1e2f26df7f291270fb461abac912ce7161..716d1226ba6925babc28bc6c14dc175e739c7f57 100644 (file)
--- a/arch/arm64/mm/init.c
+++ b/arch/arm64/mm/init.c
@@ -401,7 +401,8 @@ static void __init free_unused_memmap(void)
  */
 void __init mem_init(void)
 {
-       if (swiotlb_force || max_pfn > (arm64_dma_phys_limit >> PAGE_SHIFT))
+       if (swiotlb_force == SWIOTLB_FORCE ||
+           max_pfn > (arm64_dma_phys_limit >> PAGE_SHIFT))
                swiotlb_init(1);
 
        set_max_mapnr(pfn_to_page(max_pfn) - mem_map);

diff --git a/arch/x86/kernel/pci-swiotlb.c b/arch/x86/kernel/pci-swiotlb.c
index 36049af2715ebd13a5a463ddea442cfc24e5c9ab..410efb2c7b80028ba63367e5ed6d5e27518b0f24 100644 (file)
--- a/arch/x86/kernel/pci-swiotlb.c
+++ b/arch/x86/kernel/pci-swiotlb.c
@@ -68,7 +68,7 @@ static struct dma_map_ops swiotlb_dma_ops = {
  */
 int __init pci_swiotlb_detect_override(void)
 {
-       if (swiotlb_force)
+       if (swiotlb_force == SWIOTLB_FORCE)
                swiotlb = 1;
 
        return swiotlb;

diff --git a/arch/x86/xen/pci-swiotlb-xen.c b/arch/x86/xen/pci-swiotlb-xen.c
index a9fafb5c873897eec1685861180cf4ac5fd826e3..a0b36a9d5df149e6370fb3b6be0d5894bae72bd7 100644 (file)
--- a/arch/x86/xen/pci-swiotlb-xen.c
+++ b/arch/x86/xen/pci-swiotlb-xen.c
@@ -48,7 +48,7 @@ int __init pci_xen_swiotlb_detect(void)
         * activate this IOMMU. If running as PV privileged, activate it
         * irregardless.
         */
-       if ((xen_initial_domain() || swiotlb || swiotlb_force))
+       if (xen_initial_domain() || swiotlb || swiotlb_force == SWIOTLB_FORCE)
                xen_swiotlb = 1;
 
        /* If we are running under Xen, we MUST disable the native SWIOTLB.

diff --git a/drivers/xen/swiotlb-xen.c b/drivers/xen/swiotlb-xen.c
index 478fb91e3df2b8a9f8c75d8538668465feb59462..aba12009422e343d23723f28100fd51bf987ab00 100644 (file)
--- a/drivers/xen/swiotlb-xen.c
+++ b/drivers/xen/swiotlb-xen.c
@@ -392,7 +392,7 @@ dma_addr_t xen_swiotlb_map_page(struct device *dev, struct page *page,
        if (dma_capable(dev, dev_addr, size) &&
            !range_straddles_page_boundary(phys, size) &&
                !xen_arch_need_swiotlb(dev, phys, dev_addr) &&
-               !swiotlb_force) {
+               (swiotlb_force != SWIOTLB_FORCE)) {
                /* we are not interested in the dma_addr returned by
                 * xen_dma_map_page, only in the potential cache flushes executed
                 * by the function. */
@@ -552,7 +552,7 @@ xen_swiotlb_map_sg_attrs(struct device *hwdev, struct scatterlist *sgl,
                phys_addr_t paddr = sg_phys(sg);
                dma_addr_t dev_addr = xen_phys_to_bus(paddr);
 
-               if (swiotlb_force ||
+               if (swiotlb_force == SWIOTLB_FORCE ||
                    xen_arch_need_swiotlb(hwdev, paddr, dev_addr) ||
                    !dma_capable(hwdev, dev_addr, sg->length) ||
                    range_straddles_page_boundary(paddr, sg->length)) {

diff --git a/include/linux/swiotlb.h b/include/linux/swiotlb.h
index 183f37c8a5e164ad5864ac433dd69093bac5bad7..71d104e4c849076337e7a6c631c824886856affc 100644 (file)
--- a/include/linux/swiotlb.h
+++ b/include/linux/swiotlb.h
@@ -9,7 +9,12 @@ struct device;
 struct page;
 struct scatterlist;
 
-extern int swiotlb_force;
+enum swiotlb_force {
+       SWIOTLB_NORMAL,         /* Default - depending on HW DMA mask etc. */
+       SWIOTLB_FORCE,          /* swiotlb=force */
+};
+
+extern enum swiotlb_force swiotlb_force;
 
 /*
  * Maximum allowable number of contiguous slabs to map,

diff --git a/include/trace/events/swiotlb.h b/include/trace/events/swiotlb.h
index 7ea4c5e7c4487a963acfc75c027514a6cb360169..5e2e30a7efce0ebded6a183aca089f2fc9d31abe 100644 (file)
--- a/include/trace/events/swiotlb.h
+++ b/include/trace/events/swiotlb.h
@@ -11,16 +11,16 @@ TRACE_EVENT(swiotlb_bounced,
        TP_PROTO(struct device *dev,
                 dma_addr_t dev_addr,
                 size_t size,
-                int swiotlb_force),
+                enum swiotlb_force swiotlb_force),
 
        TP_ARGS(dev, dev_addr, size, swiotlb_force),
 
        TP_STRUCT__entry(
-               __string(       dev_name,       dev_name(dev)   )
-               __field(        u64,    dma_mask                )
-               __field(        dma_addr_t,     dev_addr        )
-               __field(        size_t, size                    )
-               __field(        int,    swiotlb_force           )
+               __string(       dev_name,       dev_name(dev)           )
+               __field(        u64,    dma_mask                        )
+               __field(        dma_addr_t,     dev_addr                )
+               __field(        size_t, size                            )
+               __field(        enum swiotlb_force,     swiotlb_force   )
        ),
 
        TP_fast_assign(
@@ -37,7 +37,9 @@ TRACE_EVENT(swiotlb_bounced,
                __entry->dma_mask,
                (unsigned long long)__entry->dev_addr,
                __entry->size,
-               __entry->swiotlb_force ? "swiotlb_force" : "" )
+               __print_symbolic(__entry->swiotlb_force,
+                       { SWIOTLB_NORMAL,       "NORMAL" },
+                       { SWIOTLB_FORCE,        "FORCE" }))
 );
 
 #endif /*  _TRACE_SWIOTLB_H */

diff --git a/lib/swiotlb.c b/lib/swiotlb.c
index cb1b54ee8527241de289ab66f34f9a0a1efa761f..a32dce6d5101f40850326b0d9e5b0e91eb87cbc1 100644 (file)
--- a/lib/swiotlb.c
+++ b/lib/swiotlb.c
@@ -53,7 +53,7 @@
  */
 #define IO_TLB_MIN_SLABS ((1<<20) >> IO_TLB_SHIFT)
 
-int swiotlb_force;
+enum swiotlb_force swiotlb_force;
 
 /*
  * Used to do a quick range check in swiotlb_tbl_unmap_single and
@@ -107,7 +107,7 @@ setup_io_tlb_npages(char *str)
        if (*str == ',')
                ++str;
        if (!strcmp(str, "force"))
-               swiotlb_force = 1;
+               swiotlb_force = SWIOTLB_FORCE;
 
        return 0;
 }
@@ -763,7 +763,7 @@ dma_addr_t swiotlb_map_page(struct device *dev, struct page *page,
         * we can safely return the device addr and not worry about bounce
         * buffering it.
         */
-       if (dma_capable(dev, dev_addr, size) && !swiotlb_force)
+       if (dma_capable(dev, dev_addr, size) && swiotlb_force != SWIOTLB_FORCE)
                return dev_addr;
 
        trace_swiotlb_bounced(dev, dev_addr, size, swiotlb_force);
@@ -904,7 +904,7 @@ swiotlb_map_sg_attrs(struct device *hwdev, struct scatterlist *sgl, int nelems,
                phys_addr_t paddr = sg_phys(sg);
                dma_addr_t dev_addr = phys_to_dma(hwdev, paddr);
 
-               if (swiotlb_force ||
+               if (swiotlb_force == SWIOTLB_FORCE ||
                    !dma_capable(hwdev, dev_addr, sg->length)) {
                        phys_addr_t map = map_single(hwdev, sg_phys(sg),
                                                     sg->length, dir, attrs);