Messages in this thread | ![/](/images/icornerl.gif) | | Date | Wed, 26 Jun 2019 11:01:22 -0700 | From | Ira Weiny <> | Subject | Re: [PATCH 08/25] memremap: validate the pagemap type passed to devm_memremap_pages |
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On Wed, Jun 26, 2019 at 02:27:07PM +0200, Christoph Hellwig wrote: > Most pgmap types are only supported when certain config options are > enabled. Check for a type that is valid for the current configuration > before setting up the pagemap. For this the usage of the 0 type for > device dax gets replaced with an explicit MEMORY_DEVICE_DEVDAX type. > > Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
> --- > drivers/dax/device.c | 1 + > include/linux/memremap.h | 8 ++++++++ > kernel/memremap.c | 22 ++++++++++++++++++++++ > 3 files changed, 31 insertions(+) > > 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); > -- > 2.20.1 > > _______________________________________________ > Linux-nvdimm mailing list > Linux-nvdimm@lists.01.org > https://lists.01.org/mailman/listinfo/linux-nvdimm
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