diff --git a/arch/powerpc/platforms/powernv/pci-ioda-tce.c b/arch/powerpc/platforms/powernv/pci-ioda-tce.c index e28f03e1eb5e..8d6569590161 100644 --- a/arch/powerpc/platforms/powernv/pci-ioda-tce.c +++ b/arch/powerpc/platforms/powernv/pci-ioda-tce.c @@ -48,6 +48,9 @@ static __be64 *pnv_alloc_tce_level(int nid, unsigned int shift) return addr; } +static void pnv_pci_ioda2_table_do_free_pages(__be64 *addr, + unsigned long size, unsigned int levels); + static __be64 *pnv_tce(struct iommu_table *tbl, bool user, long idx, bool alloc) { __be64 *tmp = user ? tbl->it_userspace : (__be64 *) tbl->it_base; @@ -57,9 +60,9 @@ static __be64 *pnv_tce(struct iommu_table *tbl, bool user, long idx, bool alloc) while (level) { int n = (idx & mask) >> (level * shift); - unsigned long tce; + unsigned long oldtce, tce = be64_to_cpu(READ_ONCE(tmp[n])); - if (tmp[n] == 0) { + if (!tce) { __be64 *tmp2; if (!alloc) @@ -70,10 +73,15 @@ static __be64 *pnv_tce(struct iommu_table *tbl, bool user, long idx, bool alloc) if (!tmp2) return NULL; - tmp[n] = cpu_to_be64(__pa(tmp2) | - TCE_PCI_READ | TCE_PCI_WRITE); + tce = __pa(tmp2) | TCE_PCI_READ | TCE_PCI_WRITE; + oldtce = be64_to_cpu(cmpxchg(&tmp[n], 0, + cpu_to_be64(tce))); + if (oldtce) { + pnv_pci_ioda2_table_do_free_pages(tmp2, + ilog2(tbl->it_level_size) + 3, 1); + tce = oldtce; + } } - tce = be64_to_cpu(tmp[n]); tmp = __va(tce & ~(TCE_PCI_READ | TCE_PCI_WRITE)); idx &= ~mask;