diff options
| -rw-r--r-- | drivers/acpi/osl.c | 28 |
1 files changed, 15 insertions, 13 deletions
diff --git a/drivers/acpi/osl.c b/drivers/acpi/osl.c index f6785bced215..445f205752a2 100644 --- a/drivers/acpi/osl.c +++ b/drivers/acpi/osl.c @@ -302,7 +302,7 @@ acpi_map_lookup_virt(void __iomem *virt, acpi_size size) void __iomem *__init_refok acpi_os_map_memory(acpi_physical_address phys, acpi_size size) { - struct acpi_ioremap *map, *tmp_map; + struct acpi_ioremap *map; void __iomem *virt; acpi_physical_address pg_off; acpi_size pg_sz; @@ -315,14 +315,25 @@ acpi_os_map_memory(acpi_physical_address phys, acpi_size size) if (!acpi_gbl_permanent_mmap) return __acpi_map_table((unsigned long)phys, size); + mutex_lock(&acpi_ioremap_lock); + /* Check if there's a suitable mapping already. */ + map = acpi_map_lookup(phys, size); + if (map) { + kref_get(&map->ref); + goto out; + } + map = kzalloc(sizeof(*map), GFP_KERNEL); - if (!map) + if (!map) { + mutex_unlock(&acpi_ioremap_lock); return NULL; + } pg_off = round_down(phys, PAGE_SIZE); pg_sz = round_up(phys + size, PAGE_SIZE) - pg_off; virt = acpi_os_ioremap(pg_off, pg_sz); if (!virt) { + mutex_unlock(&acpi_ioremap_lock); kfree(map); return NULL; } @@ -333,19 +344,10 @@ acpi_os_map_memory(acpi_physical_address phys, acpi_size size) map->size = pg_sz; kref_init(&map->ref); - mutex_lock(&acpi_ioremap_lock); - /* Check if page has already been mapped. */ - tmp_map = acpi_map_lookup(phys, size); - if (tmp_map) { - kref_get(&tmp_map->ref); - mutex_unlock(&acpi_ioremap_lock); - iounmap(map->virt); - kfree(map); - return tmp_map->virt + (phys - tmp_map->phys); - } list_add_tail_rcu(&map->list, &acpi_ioremaps); - mutex_unlock(&acpi_ioremap_lock); + out: + mutex_unlock(&acpi_ioremap_lock); return map->virt + (phys - map->phys); } EXPORT_SYMBOL_GPL(acpi_os_map_memory); |