[PATCH v7 15/24] alpha/PCI: Remove WARN from __pci_mmap_fits() and __legacy_mmap_fits()

["Krzysztof Wilczyński" <kwilczynski@kernel.org>]

Remove the WARN() that fires when userspace attempts to mmap beyond
the BAR bounds.  The check still returns 0 to reject the mapping,
but the warning is excessive for normal operation.

A similar warning was removed from the PCI core in the commit
3b519e4ea618 ("PCI: fix size checks for mmap() on /proc/bus/pci files").

Tested-by: Magnus Lindholm <linmag7@gmail.com>
Tested-by: Shivaprasad G Bhat <sbhat@linux.ibm.com>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Acked-by: Magnus Lindholm <linmag7@gmail.com>
Signed-off-by: Krzysztof Wilczyński <kwilczynski@kernel.org>
---
 arch/alpha/kernel/pci-sysfs.c | 20 ++++----------------
 1 file changed, 4 insertions(+), 16 deletions(-)

diff --git a/arch/alpha/kernel/pci-sysfs.c b/arch/alpha/kernel/pci-sysfs.c
index 8802f955256e..a8dade7d084b 100644
--- a/arch/alpha/kernel/pci-sysfs.c
+++ b/arch/alpha/kernel/pci-sysfs.c
@@ -48,13 +48,7 @@ static int __pci_mmap_fits(struct pci_dev *pdev, int num,
 	start = vma->vm_pgoff;
 	size = ((len - 1) >> (PAGE_SHIFT - shift)) + 1;
 
-	if (start < size && size - start >= nr)
-		return 1;
-	WARN(1, "process \"%s\" tried to map%s 0x%08lx-0x%08lx on %s BAR %d "
-		"(size 0x%08lx)\n",
-		current->comm, sparse ? " sparse" : "", start, start + nr,
-		pci_name(pdev), num, size);
-	return 0;
+	return start < size && size - start >= nr;
 }
 
 /**
@@ -259,7 +253,7 @@ int pci_create_resource_files(struct pci_dev *pdev)
 
 static int __legacy_mmap_fits(struct pci_controller *hose,
 			      struct vm_area_struct *vma,
-			      unsigned long res_size, int sparse)
+			      unsigned long res_size)
 {
 	unsigned long nr, start, size;
 
@@ -267,13 +261,7 @@ static int __legacy_mmap_fits(struct pci_controller *hose,
 	start = vma->vm_pgoff;
 	size = ((res_size - 1) >> PAGE_SHIFT) + 1;
 
-	if (start < size && size - start >= nr)
-		return 1;
-	WARN(1, "process \"%s\" tried to map%s 0x%08lx-0x%08lx on hose %d "
-		"(size 0x%08lx)\n",
-		current->comm, sparse ? " sparse" : "", start, start + nr,
-		hose->index, size);
-	return 0;
+	return start < size && size - start >= nr;
 }
 
 static inline int has_sparse(struct pci_controller *hose,
@@ -296,7 +284,7 @@ int pci_mmap_legacy_page_range(struct pci_bus *bus, struct vm_area_struct *vma,
 
 	res_size = (mmap_type == pci_mmap_mem) ? bus->legacy_mem->size :
 						 bus->legacy_io->size;
-	if (!__legacy_mmap_fits(hose, vma, res_size, sparse))
+	if (!__legacy_mmap_fits(hose, vma, res_size))
 		return -EINVAL;
 
 	return hose_mmap_page_range(hose, vma, mmap_type, sparse);
-- 
2.54.0