diff options
| -rw-r--r-- | arch/sh/mm/pmb.c | 140 |
1 files changed, 96 insertions, 44 deletions
diff --git a/arch/sh/mm/pmb.c b/arch/sh/mm/pmb.c index 55d21902d707..75b8861ec624 100644 --- a/arch/sh/mm/pmb.c +++ b/arch/sh/mm/pmb.c @@ -128,13 +128,67 @@ static inline unsigned long pgprot_to_pmb_flags(pgprot_t prot) return pmb_flags; } -static bool pmb_can_merge(struct pmb_entry *a, struct pmb_entry *b) +static inline bool pmb_can_merge(struct pmb_entry *a, struct pmb_entry *b) { return (b->vpn == (a->vpn + a->size)) && (b->ppn == (a->ppn + a->size)) && (b->flags == a->flags); } +static bool pmb_mapping_exists(unsigned long vaddr, phys_addr_t phys, + unsigned long size) +{ + int i; + + read_lock(&pmb_rwlock); + + for (i = 0; i < ARRAY_SIZE(pmb_entry_list); i++) { + struct pmb_entry *pmbe, *iter; + unsigned long span; + + if (!test_bit(i, pmb_map)) + continue; + + pmbe = &pmb_entry_list[i]; + + /* + * See if VPN and PPN are bounded by an existing mapping. + */ + if ((vaddr < pmbe->vpn) || (vaddr >= (pmbe->vpn + pmbe->size))) + continue; + if ((phys < pmbe->ppn) || (phys >= (pmbe->ppn + pmbe->size))) + continue; + + /* + * Now see if we're in range of a simple mapping. + */ + if (size <= pmbe->size) { + read_unlock(&pmb_rwlock); + return true; + } + + span = pmbe->size; + + /* + * Finally for sizes that involve compound mappings, walk + * the chain. + */ + for (iter = pmbe->link; iter; iter = iter->link) + span += iter->size; + + /* + * Nothing else to do if the range requirements are met. + */ + if (size <= span) { + read_unlock(&pmb_rwlock); + return true; + } + } + + read_unlock(&pmb_rwlock); + return false; +} + static bool pmb_size_valid(unsigned long size) { int i; @@ -272,64 +326,62 @@ int pmb_bolt_mapping(unsigned long vaddr, phys_addr_t phys, unsigned long size, pgprot_t prot) { struct pmb_entry *pmbp, *pmbe; - unsigned long pmb_flags; + unsigned long flags, pmb_flags; int i, mapped; if (!pmb_addr_valid(vaddr, size)) return -EFAULT; + if (pmb_mapping_exists(vaddr, phys, size)) + return 0; pmb_flags = pgprot_to_pmb_flags(prot); pmbp = NULL; -again: - for (i = mapped = 0; i < ARRAY_SIZE(pmb_sizes); i++) { - unsigned long flags; - - if (size < pmb_sizes[i].size) - continue; - - pmbe = pmb_alloc(vaddr, phys, pmb_flags | pmb_sizes[i].flag, - PMB_NO_ENTRY); - if (IS_ERR(pmbe)) { - pmb_unmap_entry(pmbp, mapped); - return PTR_ERR(pmbe); - } - - spin_lock_irqsave(&pmbe->lock, flags); + do { + for (i = mapped = 0; i < ARRAY_SIZE(pmb_sizes); i++) { + if (size < pmb_sizes[i].size) + continue; + + pmbe = pmb_alloc(vaddr, phys, pmb_flags | + pmb_sizes[i].flag, PMB_NO_ENTRY); + if (IS_ERR(pmbe)) { + pmb_unmap_entry(pmbp, mapped); + return PTR_ERR(pmbe); + } - pmbe->size = pmb_sizes[i].size; + spin_lock_irqsave(&pmbe->lock, flags); - __set_pmb_entry(pmbe); + pmbe->size = pmb_sizes[i].size; - phys += pmbe->size; - vaddr += pmbe->size; - size -= pmbe->size; + __set_pmb_entry(pmbe); - /* - * Link adjacent entries that span multiple PMB entries - * for easier tear-down. - */ - if (likely(pmbp)) { - spin_lock(&pmbp->lock); - pmbp->link = pmbe; - spin_unlock(&pmbp->lock); - } + phys += pmbe->size; + vaddr += pmbe->size; + size -= pmbe->size; - pmbp = pmbe; + /* + * Link adjacent entries that span multiple PMB + * entries for easier tear-down. + */ + if (likely(pmbp)) { + spin_lock(&pmbp->lock); + pmbp->link = pmbe; + spin_unlock(&pmbp->lock); + } - /* - * Instead of trying smaller sizes on every iteration - * (even if we succeed in allocating space), try using - * pmb_sizes[i].size again. - */ - i--; - mapped++; + pmbp = pmbe; - spin_unlock_irqrestore(&pmbe->lock, flags); - } + /* + * Instead of trying smaller sizes on every + * iteration (even if we succeed in allocating + * space), try using pmb_sizes[i].size again. + */ + i--; + mapped++; - if (size >= SZ_16M) - goto again; + spin_unlock_irqrestore(&pmbe->lock, flags); + } + } while (size >= SZ_16M); return 0; } @@ -374,7 +426,7 @@ void __iomem *pmb_remap_caller(phys_addr_t phys, unsigned long size, orig_addr = vaddr = (unsigned long)area->addr; ret = pmb_bolt_mapping(vaddr, phys, size, prot); - if (ret != 0) + if (unlikely(ret != 0)) return ERR_PTR(ret); return (void __iomem *)(offset + (char *)orig_addr); |