diff options
| -rw-r--r-- | drivers/dax/device.c | 1 | ||||
| -rw-r--r-- | include/linux/memremap.h | 8 | ||||
| -rw-r--r-- | kernel/memremap.c | 22 |
3 files changed, 31 insertions, 0 deletions
diff --git a/drivers/dax/device.c b/drivers/dax/device.c index 8465d12fecba..79014baa782d 100644 --- a/drivers/dax/device.c +++ b/drivers/dax/device.c @@ -468,6 +468,7 @@ int dev_dax_probe(struct device *dev) dev_dax->pgmap.ref = &dev_dax->ref; dev_dax->pgmap.kill = dev_dax_percpu_kill; dev_dax->pgmap.cleanup = dev_dax_percpu_exit; + dev_dax->pgmap.type = MEMORY_DEVICE_DEVDAX; addr = devm_memremap_pages(dev, &dev_dax->pgmap); if (IS_ERR(addr)) return PTR_ERR(addr); diff --git a/include/linux/memremap.h b/include/linux/memremap.h index 995c62c5a48b..0c86f2c5ac9c 100644 --- a/include/linux/memremap.h +++ b/include/linux/memremap.h @@ -45,13 +45,21 @@ struct vmem_altmap { * wakeup is used to coordinate physical address space management (ex: * fs truncate/hole punch) vs pinned pages (ex: device dma). * + * MEMORY_DEVICE_DEVDAX: + * Host memory that has similar access semantics as System RAM i.e. DMA + * coherent and supports page pinning. In contrast to + * MEMORY_DEVICE_FS_DAX, this memory is access via a device-dax + * character device. + * * MEMORY_DEVICE_PCI_P2PDMA: * Device memory residing in a PCI BAR intended for use with Peer-to-Peer * transactions. */ enum memory_type { + /* 0 is reserved to catch uninitialized type fields */ MEMORY_DEVICE_PRIVATE = 1, MEMORY_DEVICE_FS_DAX, + MEMORY_DEVICE_DEVDAX, MEMORY_DEVICE_PCI_P2PDMA, }; diff --git a/kernel/memremap.c b/kernel/memremap.c index 6e1970719dc2..abda62d1e5a3 100644 --- a/kernel/memremap.c +++ b/kernel/memremap.c @@ -157,6 +157,28 @@ void *devm_memremap_pages(struct device *dev, struct dev_pagemap *pgmap) pgprot_t pgprot = PAGE_KERNEL; int error, nid, is_ram; + switch (pgmap->type) { + case MEMORY_DEVICE_PRIVATE: + if (!IS_ENABLED(CONFIG_DEVICE_PRIVATE)) { + WARN(1, "Device private memory not supported\n"); + return ERR_PTR(-EINVAL); + } + break; + case MEMORY_DEVICE_FS_DAX: + if (!IS_ENABLED(CONFIG_ZONE_DEVICE) || + IS_ENABLED(CONFIG_FS_DAX_LIMITED)) { + WARN(1, "File system DAX not supported\n"); + return ERR_PTR(-EINVAL); + } + break; + case MEMORY_DEVICE_DEVDAX: + case MEMORY_DEVICE_PCI_P2PDMA: + break; + default: + WARN(1, "Invalid pgmap type %d\n", pgmap->type); + break; + } + if (!pgmap->ref || !pgmap->kill || !pgmap->cleanup) { WARN(1, "Missing reference count teardown definition\n"); return ERR_PTR(-EINVAL); |