iommu: Defer the early return in arm_(v7s/lpae)_map

Although handling a mapping request with no permissions is a
trivial no-op, defer the early return until after the size/range
checks so that we are consistent with other mapping requests.

Signed-off-by: Keqian Zhu <zhukeqian1@huawei.com>
Link: https://lore.kernel.org/r/20201207115758.9400-1-zhukeqian1@huawei.com
Signed-off-by: Will Deacon <will@kernel.org>

diff --git a/drivers/iommu/io-pgtable-arm-v7s.c b/drivers/iommu/io-pgtable-arm-v7s.c
index a688f22cbe3b590cce25bf1ca4e490d4a8c8bdb0..359b96b0fa3ea2a3ebd48ae8ba7e73ad55967101 100644 (file)
--- a/drivers/iommu/io-pgtable-arm-v7s.c
+++ b/drivers/iommu/io-pgtable-arm-v7s.c
@@ -522,14 +522,14 @@ static int arm_v7s_map(struct io_pgtable_ops *ops, unsigned long iova,
        struct io_pgtable *iop = &data->iop;
        int ret;
 
-       /* If no access, then nothing to do */
-       if (!(prot & (IOMMU_READ | IOMMU_WRITE)))
-               return 0;
-
        if (WARN_ON(iova >= (1ULL << data->iop.cfg.ias) ||
                    paddr >= (1ULL << data->iop.cfg.oas)))
                return -ERANGE;
 
+       /* If no access, then nothing to do */
+       if (!(prot & (IOMMU_READ | IOMMU_WRITE)))
+               return 0;
+
        ret = __arm_v7s_map(data, iova, paddr, size, prot, 1, data->pgd, gfp);
        /*
         * Synchronise all PTE updates for the new mapping before there's

diff --git a/drivers/iommu/io-pgtable-arm.c b/drivers/iommu/io-pgtable-arm.c
index a7a9bc08dcd115c39633f7661303e4a21e0d23b2..8ade72adab315626b8f345f1c8c4962da9fcccc2 100644 (file)
--- a/drivers/iommu/io-pgtable-arm.c
+++ b/drivers/iommu/io-pgtable-arm.c
@@ -444,10 +444,6 @@ static int arm_lpae_map(struct io_pgtable_ops *ops, unsigned long iova,
        arm_lpae_iopte prot;
        long iaext = (s64)iova >> cfg->ias;
 
-       /* If no access, then nothing to do */
-       if (!(iommu_prot & (IOMMU_READ | IOMMU_WRITE)))
-               return 0;
-
        if (WARN_ON(!size || (size & cfg->pgsize_bitmap) != size))
                return -EINVAL;
 
@@ -456,6 +452,10 @@ static int arm_lpae_map(struct io_pgtable_ops *ops, unsigned long iova,
        if (WARN_ON(iaext || paddr >> cfg->oas))
                return -ERANGE;
 
+       /* If no access, then nothing to do */
+       if (!(iommu_prot & (IOMMU_READ | IOMMU_WRITE)))
+               return 0;
+
        prot = arm_lpae_prot_to_pte(data, iommu_prot);
        ret = __arm_lpae_map(data, iova, paddr, size, prot, lvl, ptep, gfp);
        /*