cleanup IORESOURCE_CACHEABLE vs ioremap()

Quoting Arnd:
    I was thinking the opposite approach and basically removing all uses
    of IORESOURCE_CACHEABLE from the kernel. There are only a handful of
    them.and we can probably replace them all with hardcoded
    ioremap_cached() calls in the cases they are actually useful.

All existing usages of IORESOURCE_CACHEABLE call ioremap() instead of
ioremap_nocache() if the resource is cacheable, however ioremap() is
uncached by default. Clearly none of the existing usages care about the
cacheability. Particularly devm_ioremap_resource() never worked as
advertised since it always fell back to plain ioremap().

Clean this up as the new direction we want is to convert
ioremap_<type>() usages to memremap(..., flags).

Suggested-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

11 files changed, 16 insertions, 44 deletions

diff --git a/arch/arm/mach-clps711x/board-cdb89712.c b/arch/arm/mach-clps711x/board-cdb89712.c
index 1ec378c334e5..972abdb10028 100644
--- a/arch/arm/mach-clps711x/board-cdb89712.c
+++ b/arch/arm/mach-clps711x/board-cdb89712.c
@@ -95,7 +95,7 @@ static struct physmap_flash_data cdb89712_bootrom_pdata __initdata = {
 
 static struct resource cdb89712_bootrom_resources[] __initdata = {
         DEFINE_RES_NAMED(CS7_PHYS_BASE, SZ_128, "BOOTROM", IORESOURCE_MEM |
-                         IORESOURCE_CACHEABLE | IORESOURCE_READONLY),
+                         IORESOURCE_READONLY),
 };
 
 static struct platform_device cdb89712_bootrom_pdev __initdata = {
diff --git a/arch/powerpc/kernel/pci_of_scan.c b/arch/powerpc/kernel/pci_of_scan.c
index 42e02a2d570b..d4726addff0b 100644
--- a/arch/powerpc/kernel/pci_of_scan.c
+++ b/arch/powerpc/kernel/pci_of_scan.c
@@ -102,7 +102,7 @@ static void of_pci_parse_addrs(struct device_node *node, struct pci_dev *dev)
                         res = &dev->resource[(i - PCI_BASE_ADDRESS_0) >> 2];
                 } else if (i == dev->rom_base_reg) {
                         res = &dev->resource[PCI_ROM_RESOURCE];
-                        flags |= IORESOURCE_READONLY | IORESOURCE_CACHEABLE;
+                        flags |= IORESOURCE_READONLY;
                 } else {
                         printk(KERN_ERR "PCI: bad cfg reg num 0x%x\n", i);
                         continue;
diff --git a/arch/sparc/kernel/pci.c b/arch/sparc/kernel/pci.c
index c928bc64b4ba..04da147e0712 100644
--- a/arch/sparc/kernel/pci.c
+++ b/arch/sparc/kernel/pci.c
@@ -231,8 +231,7 @@ static void pci_parse_of_addrs(struct platform_device *op,
                         res = &dev->resource[(i - PCI_BASE_ADDRESS_0) >> 2];
                 } else if (i == dev->rom_base_reg) {
                         res = &dev->resource[PCI_ROM_RESOURCE];
-                        flags |= IORESOURCE_READONLY | IORESOURCE_CACHEABLE
-                              | IORESOURCE_SIZEALIGN;
+                        flags |= IORESOURCE_READONLY | IORESOURCE_SIZEALIGN;
                 } else {
                         printk(KERN_ERR "PCI: bad cfg reg num 0x%x\n", i);
                         continue;
diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index cefd636681b6..8ed37dd04056 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -326,8 +326,7 @@ static void pci_read_bases(struct pci_dev *dev, unsigned int howmany, int rom)
                 struct resource *res = &dev->resource[PCI_ROM_RESOURCE];
                 dev->rom_base_reg = rom;
                 res->flags = IORESOURCE_MEM | IORESOURCE_PREFETCH |
-                                IORESOURCE_READONLY | IORESOURCE_CACHEABLE |
-                                IORESOURCE_SIZEALIGN;
+                                IORESOURCE_READONLY | IORESOURCE_SIZEALIGN;
                 __pci_read_base(dev, pci_bar_mem32, res, rom);
         }
 }
diff --git a/drivers/pnp/manager.c b/drivers/pnp/manager.c
index 9357aa779048..7ad3295752ef 100644
--- a/drivers/pnp/manager.c
+++ b/drivers/pnp/manager.c
@@ -97,8 +97,6 @@ static int pnp_assign_mem(struct pnp_dev *dev, struct pnp_mem *rule, int idx)
         /* ??? rule->flags restricted to 8 bits, all tests bogus ??? */
         if (!(rule->flags & IORESOURCE_MEM_WRITEABLE))
                 res->flags |= IORESOURCE_READONLY;
-        if (rule->flags & IORESOURCE_MEM_CACHEABLE)
-                res->flags |= IORESOURCE_CACHEABLE;
         if (rule->flags & IORESOURCE_MEM_RANGELENGTH)
                 res->flags |= IORESOURCE_RANGELENGTH;
         if (rule->flags & IORESOURCE_MEM_SHADOWABLE)
diff --git a/drivers/scsi/aic94xx/aic94xx_init.c b/drivers/scsi/aic94xx/aic94xx_init.c
index 4b135cca42a1..140cb8e6fea2 100644
--- a/drivers/scsi/aic94xx/aic94xx_init.c
+++ b/drivers/scsi/aic94xx/aic94xx_init.c
@@ -100,12 +100,7 @@ static int asd_map_memio(struct asd_ha_struct *asd_ha)
                                    pci_name(asd_ha->pcidev));
                         goto Err;
                 }
-                if (io_handle->flags & IORESOURCE_CACHEABLE)
-                        io_handle->addr = ioremap(io_handle->start,
-                                                  io_handle->len);
-                else
-                        io_handle->addr = ioremap_nocache(io_handle->start,
-                                                          io_handle->len);
+                io_handle->addr = ioremap(io_handle->start, io_handle->len);
                 if (!io_handle->addr) {
                         asd_printk("couldn't map MBAR%d of %s\n", i==0?0:1,
                                    pci_name(asd_ha->pcidev));
diff --git a/drivers/scsi/arcmsr/arcmsr_hba.c b/drivers/scsi/arcmsr/arcmsr_hba.c
index 914c39f9f388..e4f77cad9fd8 100644
--- a/drivers/scsi/arcmsr/arcmsr_hba.c
+++ b/drivers/scsi/arcmsr/arcmsr_hba.c
@@ -259,10 +259,7 @@ static bool arcmsr_remap_pciregion(struct AdapterControlBlock *acb)
                 addr = (unsigned long)pci_resource_start(pdev, 0);
                 range = pci_resource_len(pdev, 0);
                 flags = pci_resource_flags(pdev, 0);
-                if (flags & IORESOURCE_CACHEABLE)
-                        mem_base0 = ioremap(addr, range);
-                else
-                        mem_base0 = ioremap_nocache(addr, range);
+                mem_base0 = ioremap(addr, range);
                 if (!mem_base0) {
                         pr_notice("arcmsr%d: memory mapping region fail\n",
                                 acb->host->host_no);
diff --git a/drivers/scsi/mvsas/mv_init.c b/drivers/scsi/mvsas/mv_init.c
index d40d734aa53a..e654b5cec69e 100644
--- a/drivers/scsi/mvsas/mv_init.c
+++ b/drivers/scsi/mvsas/mv_init.c
@@ -324,13 +324,9 @@ int mvs_ioremap(struct mvs_info *mvi, int bar, int bar_ex)
                         goto err_out;
 
                 res_flag_ex = pci_resource_flags(pdev, bar_ex);
-                if (res_flag_ex & IORESOURCE_MEM) {
-                        if (res_flag_ex & IORESOURCE_CACHEABLE)
-                                mvi->regs_ex = ioremap(res_start, res_len);
-                        else
-                                mvi->regs_ex = ioremap_nocache(res_start,
-                                                res_len);
-                } else
+                if (res_flag_ex & IORESOURCE_MEM)
+                        mvi->regs_ex = ioremap(res_start, res_len);
+                else
                         mvi->regs_ex = (void *)res_start;
                 if (!mvi->regs_ex)
                         goto err_out;
@@ -342,10 +338,7 @@ int mvs_ioremap(struct mvs_info *mvi, int bar, int bar_ex)
                 goto err_out;
 
         res_flag = pci_resource_flags(pdev, bar);
-        if (res_flag & IORESOURCE_CACHEABLE)
-                mvi->regs = ioremap(res_start, res_len);
-        else
-                mvi->regs = ioremap_nocache(res_start, res_len);
+        mvi->regs = ioremap(res_start, res_len);
 
         if (!mvi->regs) {
                 if (mvi->regs_ex && (res_flag_ex & IORESOURCE_MEM))
diff --git a/drivers/video/fbdev/ocfb.c b/drivers/video/fbdev/ocfb.c
index de9819660ca0..c9293aea8ec3 100644
--- a/drivers/video/fbdev/ocfb.c
+++ b/drivers/video/fbdev/ocfb.c
@@ -325,7 +325,6 @@ static int ocfb_probe(struct platform_device *pdev)
                 dev_err(&pdev->dev, "I/O resource request failed\n");
                 return -ENXIO;
         }
-        res->flags &= ~IORESOURCE_CACHEABLE;
         fbdev->regs = devm_ioremap_resource(&pdev->dev, res);
         if (IS_ERR(fbdev->regs))
                 return PTR_ERR(fbdev->regs);
diff --git a/lib/devres.c b/lib/devres.c
index fbe2aac522e6..f13a2468ff39 100644
--- a/lib/devres.c
+++ b/lib/devres.c
@@ -119,10 +119,9 @@ EXPORT_SYMBOL(devm_iounmap);
  * @dev: generic device to handle the resource for
  * @res: resource to be handled
  *
- * Checks that a resource is a valid memory region, requests the memory region
- * and ioremaps it either as cacheable or as non-cacheable memory depending on
- * the resource's flags. All operations are managed and will be undone on
- * driver detach.
+ * Checks that a resource is a valid memory region, requests the memory
+ * region and ioremaps it. All operations are managed and will be undone
+ * on driver detach.
  *
  * Returns a pointer to the remapped memory or an ERR_PTR() encoded error code
  * on failure. Usage example:
@@ -153,11 +152,7 @@ void __iomem *devm_ioremap_resource(struct device *dev, struct resource *res)
                 return IOMEM_ERR_PTR(-EBUSY);
         }
 
-        if (res->flags & IORESOURCE_CACHEABLE)
-                dest_ptr = devm_ioremap(dev, res->start, size);
-        else
-                dest_ptr = devm_ioremap_nocache(dev, res->start, size);
-
+        dest_ptr = devm_ioremap(dev, res->start, size);
         if (!dest_ptr) {
                 dev_err(dev, "ioremap failed for resource %pR\n", res);
                 devm_release_mem_region(dev, res->start, size);
diff --git a/lib/pci_iomap.c b/lib/pci_iomap.c
index bcce5f149310..e1930dbab2da 100644
--- a/lib/pci_iomap.c
+++ b/lib/pci_iomap.c
@@ -41,11 +41,8 @@ void __iomem *pci_iomap_range(struct pci_dev *dev,
                 len = maxlen;
         if (flags & IORESOURCE_IO)
                 return __pci_ioport_map(dev, start, len);
-        if (flags & IORESOURCE_MEM) {
-                if (flags & IORESOURCE_CACHEABLE)
-                        return ioremap(start, len);
-                return ioremap_nocache(start, len);
-        }
+        if (flags & IORESOURCE_MEM)
+                return ioremap(start, len);
         /* What? */
         return NULL;
 }