| Message ID | 20180212183352.22730-17-jean-philippe.brucker@arm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Mon, 12 Feb 2018 18:33:31 +0000 Jean-Philippe Brucker <jean-philippe.brucker@arm.com> wrote: > Add a small API within the IOMMU subsystem to handle different > formats of PASID tables. It uses the same principle as io-pgtable: > > * The IOMMU driver registers a PASID table with some invalidation > callbacks. > * The pasid-table lib allocates a set of tables of the right format, > and returns an iommu_pasid_table_ops structure. > * The IOMMU driver allocates entries and writes them using the > provided ops. > * The pasid-table lib calls the IOMMU driver back for invalidation > when necessary. > * The IOMMU driver unregisters the ops which frees the tables when > finished. > > An example user will be Arm SMMU in a subsequent patch. > > Signed-off-by: Jean-Philippe Brucker <jean-philippe.brucker@arm.com> > --- > drivers/iommu/Kconfig | 8 +++ > drivers/iommu/Makefile | 1 + > drivers/iommu/iommu-pasid.c | 53 +++++++++++++++++ > drivers/iommu/iommu-pasid.h | 142 > ++++++++++++++++++++++++++++++++++++++++++++ 4 files changed, 204 > insertions(+) create mode 100644 drivers/iommu/iommu-pasid.c > create mode 100644 drivers/iommu/iommu-pasid.h > > diff --git a/drivers/iommu/Kconfig b/drivers/iommu/Kconfig > index e751bb9958ba..8add90ba9b75 100644 > --- a/drivers/iommu/Kconfig > +++ b/drivers/iommu/Kconfig > @@ -60,6 +60,14 @@ config IOMMU_IO_PGTABLE_ARMV7S_SELFTEST > > endmenu > > +menu "Generic PASID table support" > + > +# Selected by the actual PASID table implementations > +config IOMMU_PASID_TABLE > + bool > + > +endmenu > + > config IOMMU_IOVA > tristate > > diff --git a/drivers/iommu/Makefile b/drivers/iommu/Makefile > index f4324e29035e..338e59c93131 100644 > --- a/drivers/iommu/Makefile > +++ b/drivers/iommu/Makefile > @@ -8,6 +8,7 @@ obj-$(CONFIG_IOMMU_FAULT) += io-pgfault.o > obj-$(CONFIG_IOMMU_IO_PGTABLE) += io-pgtable.o > obj-$(CONFIG_IOMMU_IO_PGTABLE_ARMV7S) += io-pgtable-arm-v7s.o > obj-$(CONFIG_IOMMU_IO_PGTABLE_LPAE) += io-pgtable-arm.o > +obj-$(CONFIG_IOMMU_PASID_TABLE) += iommu-pasid.o > obj-$(CONFIG_IOMMU_IOVA) += iova.o > obj-$(CONFIG_OF_IOMMU) += of_iommu.o > obj-$(CONFIG_MSM_IOMMU) += msm_iommu.o > diff --git a/drivers/iommu/iommu-pasid.c b/drivers/iommu/iommu-pasid.c > new file mode 100644 > index 000000000000..6b21d369d514 > --- /dev/null > +++ b/drivers/iommu/iommu-pasid.c > @@ -0,0 +1,53 @@ > +/* > + * PASID table management for the IOMMU > + * > + * Copyright (C) 2018 ARM Ltd. > + * Author: Jean-Philippe Brucker <jean-philippe.brucker@arm.com> > + * > + * SPDX-License-Identifier: GPL-2.0 > + */ > + > +#include <linux/kernel.h> > + > +#include "iommu-pasid.h" > + > +static const struct iommu_pasid_init_fns * > +pasid_table_init_fns[PASID_TABLE_NUM_FMTS] = { > +}; > + > +struct iommu_pasid_table_ops * > +iommu_alloc_pasid_ops(enum iommu_pasid_table_fmt fmt, > + struct iommu_pasid_table_cfg *cfg, void > *cookie) +{ I guess you don't need to pass in cookie here. > + struct iommu_pasid_table *table; > + const struct iommu_pasid_init_fns *fns; > + > + if (fmt >= PASID_TABLE_NUM_FMTS) > + return NULL; > + > + fns = pasid_table_init_fns[fmt]; > + if (!fns) > + return NULL; > + > + table = fns->alloc(cfg, cookie); > + if (!table) > + return NULL; > + > + table->fmt = fmt; > + table->cookie = cookie; > + table->cfg = *cfg; > + the ops is already IOMMU model specific, why do you need to pass cfg back? > + return &table->ops; If there is no common code that uses these ops, I don't see the benefit of having these APIs. Or the plan is to consolidate even further such that referene to pasid table can be attached at per iommu_domain etc, but that would be model specific choice. Jacob > +} > + > +void iommu_free_pasid_ops(struct iommu_pasid_table_ops *ops) > +{ > + struct iommu_pasid_table *table; > + > + if (!ops) > + return; > + > + table = container_of(ops, struct iommu_pasid_table, ops); > + iommu_pasid_flush_all(table); > + pasid_table_init_fns[table->fmt]->free(table); > +} > diff --git a/drivers/iommu/iommu-pasid.h b/drivers/iommu/iommu-pasid.h > new file mode 100644 > index 000000000000..40a27d35c1e0 > --- /dev/null > +++ b/drivers/iommu/iommu-pasid.h > @@ -0,0 +1,142 @@ > +/* > + * PASID table management for the IOMMU > + * > + * Copyright (C) 2017 ARM Ltd. > + * Author: Jean-Philippe Brucker <jean-philippe.brucker@arm.com> > + * > + * SPDX-License-Identifier: GPL-2.0 > + */ > +#ifndef __IOMMU_PASID_H > +#define __IOMMU_PASID_H > + > +#include <linux/types.h> > +#include "io-pgtable.h" > + > +struct mm_struct; > + > +enum iommu_pasid_table_fmt { > + PASID_TABLE_NUM_FMTS, > +}; > + > +/** > + * iommu_pasid_entry - Entry of a PASID table > + * > + * @token: architecture-specific data needed to uniquely > identify the > + * entry. Most notably used for TLB invalidation > + */ > +struct iommu_pasid_entry { > + u64 tag; > +}; > + > +/** > + * iommu_pasid_table_ops - Operations on a PASID table > + * > + * @alloc_shared_entry: allocate an entry for sharing an mm > (SVA) > + * Returns the pointer to a new entry or an > error > + * @alloc_priv_entry: allocate an entry for map/unmap > operations > + * Returns the pointer to a new entry or an > error > + * @free_entry: free an entry obtained with > alloc_entry > + * @set_entry: write PASID table entry > + * @clear_entry: clear PASID table entry > + */ > +struct iommu_pasid_table_ops { > + struct iommu_pasid_entry * > + (*alloc_shared_entry)(struct iommu_pasid_table_ops *ops, > + struct mm_struct *mm); > + struct iommu_pasid_entry * > + (*alloc_priv_entry)(struct iommu_pasid_table_ops *ops, > + enum io_pgtable_fmt fmt, > + struct io_pgtable_cfg *cfg); > + void (*free_entry)(struct iommu_pasid_table_ops *ops, > + struct iommu_pasid_entry *entry); > + int (*set_entry)(struct iommu_pasid_table_ops *ops, int > pasid, > + struct iommu_pasid_entry *entry); > + void (*clear_entry)(struct iommu_pasid_table_ops *ops, int > pasid, > + struct iommu_pasid_entry *entry); > +}; > + > +/** > + * iommu_pasid_sync_ops - Callbacks into the IOMMU driver > + * > + * @cfg_flush: flush cached configuration for one > entry. For a > + * multi-level PASID table, 'leaf' tells > whether to only > + * flush cached leaf entries or intermediate > levels as > + * well. > + * @cfg_flush_all: flush cached configuration for all entries > of the PASID > + * table > + * @tlb_flush: flush TLB entries for one entry > + */ > +struct iommu_pasid_sync_ops { > + void (*cfg_flush)(void *cookie, int pasid, bool leaf); > + void (*cfg_flush_all)(void *cookie); > + void (*tlb_flush)(void *cookie, int pasid, > + struct iommu_pasid_entry *entry); > +}; > + > +/** > + * struct iommu_pasid_table_cfg - Configuration data for a set of > PASID tables. > + * > + * @iommu_dev device performing the DMA table walks > + * @order: number of PASID bits, set by IOMMU driver > + * @flush: TLB management callbacks for this set of tables. > + * > + * @base: DMA address of the allocated table, set by the > allocator. > + */ > +struct iommu_pasid_table_cfg { > + struct device *iommu_dev; > + size_t order; > + const struct iommu_pasid_sync_ops *sync; > + > + dma_addr_t base; > +}; > + > +struct iommu_pasid_table_ops * > +iommu_alloc_pasid_ops(enum iommu_pasid_table_fmt fmt, > + struct iommu_pasid_table_cfg *cfg, > + void *cookie); > +void iommu_free_pasid_ops(struct iommu_pasid_table_ops *ops); > + > +/** > + * struct iommu_pasid_table - describes a set of PASID tables > + * > + * @fmt: The PASID table format. > + * @cookie: An opaque token provided by the IOMMU driver and > passed back to > + * any callback routine. > + * @cfg: A copy of the PASID table configuration. > + * @ops: The PASID table operations in use for this set of > page tables. > + */ > +struct iommu_pasid_table { > + enum iommu_pasid_table_fmt fmt; > + void *cookie; > + struct iommu_pasid_table_cfg cfg; > + struct iommu_pasid_table_ops ops; > +}; > + > +#define iommu_pasid_table_ops_to_table(ops) \ > + container_of((ops), struct iommu_pasid_table, ops) > + > +struct iommu_pasid_init_fns { > + struct iommu_pasid_table *(*alloc)(struct > iommu_pasid_table_cfg *cfg, > + void *cookie); > + void (*free)(struct iommu_pasid_table *table); > +}; > + > +static inline void iommu_pasid_flush_all(struct iommu_pasid_table > *table) +{ > + table->cfg.sync->cfg_flush_all(table->cookie); > +} > + > +static inline void iommu_pasid_flush(struct iommu_pasid_table *table, > + int pasid, bool leaf) > +{ > + table->cfg.sync->cfg_flush(table->cookie, pasid, leaf); > +} > + > +static inline void iommu_pasid_flush_tlbs(struct iommu_pasid_table > *table, > + int pasid, > + struct iommu_pasid_entry > *entry) +{ > + table->cfg.sync->tlb_flush(table->cookie, pasid, entry); > +} > + > +#endif /* __IOMMU_PASID_H */ [Jacob Pan]
On 27/02/18 18:51, Jacob Pan wrote: [...] >> +struct iommu_pasid_table_ops * >> +iommu_alloc_pasid_ops(enum iommu_pasid_table_fmt fmt, >> + struct iommu_pasid_table_cfg *cfg, void >> *cookie) +{ > I guess you don't need to pass in cookie here. The cookie is stored in the table driver and passed back to the IOMMU driver when invalidating a PASID table entry >> + struct iommu_pasid_table *table; >> + const struct iommu_pasid_init_fns *fns; >> + >> + if (fmt >= PASID_TABLE_NUM_FMTS) >> + return NULL; >> + >> + fns = pasid_table_init_fns[fmt]; >> + if (!fns) >> + return NULL; >> + >> + table = fns->alloc(cfg, cookie); >> + if (!table) >> + return NULL; >> + >> + table->fmt = fmt; >> + table->cookie = cookie; >> + table->cfg = *cfg; >> + > the ops is already IOMMU model specific, why do you need to pass cfg > back? The table driver needs some config information at runtime. Callbacks such as iommu_pasid_table_ops::alloc_shared_entry() receive the iommu_pasid_table_ops instance as argument. They can then get the iommu_pasid_table structure with container_of() and retrieve the config stored in table->cfg. >> + return &table->ops; > If there is no common code that uses these ops, I don't see the benefit > of having these APIs. Or the plan is to consolidate even further such > that referene to pasid table can be attached at per iommu_domain etc, > but that would be model specific choice. I don't plan to consolidate further. This API is for multiple IOMMU drivers with different transports implementing the same PASID table formats. For example my vSVA implementation uses this API in virtio-iommu for assigning PASID tables to the guest (All fairly experimental at this point. I initially intended to assign just the page directories, but passing the whole PASID table seemed more popular.) In the future there might be other vendor IOMMUs implementing the same PASID table formats, just like there are currently 6 IOMMU drivers using the page-table code implemented by the io-pgtable.c lib (which I copied in this patch). Thanks, Jean
diff --git a/drivers/iommu/Kconfig b/drivers/iommu/Kconfig index e751bb9958ba..8add90ba9b75 100644 --- a/drivers/iommu/Kconfig +++ b/drivers/iommu/Kconfig @@ -60,6 +60,14 @@ config IOMMU_IO_PGTABLE_ARMV7S_SELFTEST endmenu +menu "Generic PASID table support" + +# Selected by the actual PASID table implementations +config IOMMU_PASID_TABLE + bool + +endmenu + config IOMMU_IOVA tristate diff --git a/drivers/iommu/Makefile b/drivers/iommu/Makefile index f4324e29035e..338e59c93131 100644 --- a/drivers/iommu/Makefile +++ b/drivers/iommu/Makefile @@ -8,6 +8,7 @@ obj-$(CONFIG_IOMMU_FAULT) += io-pgfault.o obj-$(CONFIG_IOMMU_IO_PGTABLE) += io-pgtable.o obj-$(CONFIG_IOMMU_IO_PGTABLE_ARMV7S) += io-pgtable-arm-v7s.o obj-$(CONFIG_IOMMU_IO_PGTABLE_LPAE) += io-pgtable-arm.o +obj-$(CONFIG_IOMMU_PASID_TABLE) += iommu-pasid.o obj-$(CONFIG_IOMMU_IOVA) += iova.o obj-$(CONFIG_OF_IOMMU) += of_iommu.o obj-$(CONFIG_MSM_IOMMU) += msm_iommu.o diff --git a/drivers/iommu/iommu-pasid.c b/drivers/iommu/iommu-pasid.c new file mode 100644 index 000000000000..6b21d369d514 --- /dev/null +++ b/drivers/iommu/iommu-pasid.c @@ -0,0 +1,53 @@ +/* + * PASID table management for the IOMMU + * + * Copyright (C) 2018 ARM Ltd. + * Author: Jean-Philippe Brucker <jean-philippe.brucker@arm.com> + * + * SPDX-License-Identifier: GPL-2.0 + */ + +#include <linux/kernel.h> + +#include "iommu-pasid.h" + +static const struct iommu_pasid_init_fns * +pasid_table_init_fns[PASID_TABLE_NUM_FMTS] = { +}; + +struct iommu_pasid_table_ops * +iommu_alloc_pasid_ops(enum iommu_pasid_table_fmt fmt, + struct iommu_pasid_table_cfg *cfg, void *cookie) +{ + struct iommu_pasid_table *table; + const struct iommu_pasid_init_fns *fns; + + if (fmt >= PASID_TABLE_NUM_FMTS) + return NULL; + + fns = pasid_table_init_fns[fmt]; + if (!fns) + return NULL; + + table = fns->alloc(cfg, cookie); + if (!table) + return NULL; + + table->fmt = fmt; + table->cookie = cookie; + table->cfg = *cfg; + + return &table->ops; +} + +void iommu_free_pasid_ops(struct iommu_pasid_table_ops *ops) +{ + struct iommu_pasid_table *table; + + if (!ops) + return; + + table = container_of(ops, struct iommu_pasid_table, ops); + iommu_pasid_flush_all(table); + pasid_table_init_fns[table->fmt]->free(table); +} diff --git a/drivers/iommu/iommu-pasid.h b/drivers/iommu/iommu-pasid.h new file mode 100644 index 000000000000..40a27d35c1e0 --- /dev/null +++ b/drivers/iommu/iommu-pasid.h @@ -0,0 +1,142 @@ +/* + * PASID table management for the IOMMU + * + * Copyright (C) 2017 ARM Ltd. + * Author: Jean-Philippe Brucker <jean-philippe.brucker@arm.com> + * + * SPDX-License-Identifier: GPL-2.0 + */ +#ifndef __IOMMU_PASID_H +#define __IOMMU_PASID_H + +#include <linux/types.h> +#include "io-pgtable.h" + +struct mm_struct; + +enum iommu_pasid_table_fmt { + PASID_TABLE_NUM_FMTS, +}; + +/** + * iommu_pasid_entry - Entry of a PASID table + * + * @token: architecture-specific data needed to uniquely identify the + * entry. Most notably used for TLB invalidation + */ +struct iommu_pasid_entry { + u64 tag; +}; + +/** + * iommu_pasid_table_ops - Operations on a PASID table + * + * @alloc_shared_entry: allocate an entry for sharing an mm (SVA) + * Returns the pointer to a new entry or an error + * @alloc_priv_entry: allocate an entry for map/unmap operations + * Returns the pointer to a new entry or an error + * @free_entry: free an entry obtained with alloc_entry + * @set_entry: write PASID table entry + * @clear_entry: clear PASID table entry + */ +struct iommu_pasid_table_ops { + struct iommu_pasid_entry * + (*alloc_shared_entry)(struct iommu_pasid_table_ops *ops, + struct mm_struct *mm); + struct iommu_pasid_entry * + (*alloc_priv_entry)(struct iommu_pasid_table_ops *ops, + enum io_pgtable_fmt fmt, + struct io_pgtable_cfg *cfg); + void (*free_entry)(struct iommu_pasid_table_ops *ops, + struct iommu_pasid_entry *entry); + int (*set_entry)(struct iommu_pasid_table_ops *ops, int pasid, + struct iommu_pasid_entry *entry); + void (*clear_entry)(struct iommu_pasid_table_ops *ops, int pasid, + struct iommu_pasid_entry *entry); +}; + +/** + * iommu_pasid_sync_ops - Callbacks into the IOMMU driver + * + * @cfg_flush: flush cached configuration for one entry. For a + * multi-level PASID table, 'leaf' tells whether to only + * flush cached leaf entries or intermediate levels as + * well. + * @cfg_flush_all: flush cached configuration for all entries of the PASID + * table + * @tlb_flush: flush TLB entries for one entry + */ +struct iommu_pasid_sync_ops { + void (*cfg_flush)(void *cookie, int pasid, bool leaf); + void (*cfg_flush_all)(void *cookie); + void (*tlb_flush)(void *cookie, int pasid, + struct iommu_pasid_entry *entry); +}; + +/** + * struct iommu_pasid_table_cfg - Configuration data for a set of PASID tables. + * + * @iommu_dev device performing the DMA table walks + * @order: number of PASID bits, set by IOMMU driver + * @flush: TLB management callbacks for this set of tables. + * + * @base: DMA address of the allocated table, set by the allocator. + */ +struct iommu_pasid_table_cfg { + struct device *iommu_dev; + size_t order; + const struct iommu_pasid_sync_ops *sync; + + dma_addr_t base; +}; + +struct iommu_pasid_table_ops * +iommu_alloc_pasid_ops(enum iommu_pasid_table_fmt fmt, + struct iommu_pasid_table_cfg *cfg, + void *cookie); +void iommu_free_pasid_ops(struct iommu_pasid_table_ops *ops); + +/** + * struct iommu_pasid_table - describes a set of PASID tables + * + * @fmt: The PASID table format. + * @cookie: An opaque token provided by the IOMMU driver and passed back to + * any callback routine. + * @cfg: A copy of the PASID table configuration. + * @ops: The PASID table operations in use for this set of page tables. + */ +struct iommu_pasid_table { + enum iommu_pasid_table_fmt fmt; + void *cookie; + struct iommu_pasid_table_cfg cfg; + struct iommu_pasid_table_ops ops; +}; + +#define iommu_pasid_table_ops_to_table(ops) \ + container_of((ops), struct iommu_pasid_table, ops) + +struct iommu_pasid_init_fns { + struct iommu_pasid_table *(*alloc)(struct iommu_pasid_table_cfg *cfg, + void *cookie); + void (*free)(struct iommu_pasid_table *table); +}; + +static inline void iommu_pasid_flush_all(struct iommu_pasid_table *table) +{ + table->cfg.sync->cfg_flush_all(table->cookie); +} + +static inline void iommu_pasid_flush(struct iommu_pasid_table *table, + int pasid, bool leaf) +{ + table->cfg.sync->cfg_flush(table->cookie, pasid, leaf); +} + +static inline void iommu_pasid_flush_tlbs(struct iommu_pasid_table *table, + int pasid, + struct iommu_pasid_entry *entry) +{ + table->cfg.sync->tlb_flush(table->cookie, pasid, entry); +} + +#endif /* __IOMMU_PASID_H */
Add a small API within the IOMMU subsystem to handle different formats of PASID tables. It uses the same principle as io-pgtable: * The IOMMU driver registers a PASID table with some invalidation callbacks. * The pasid-table lib allocates a set of tables of the right format, and returns an iommu_pasid_table_ops structure. * The IOMMU driver allocates entries and writes them using the provided ops. * The pasid-table lib calls the IOMMU driver back for invalidation when necessary. * The IOMMU driver unregisters the ops which frees the tables when finished. An example user will be Arm SMMU in a subsequent patch. Signed-off-by: Jean-Philippe Brucker <jean-philippe.brucker@arm.com> --- drivers/iommu/Kconfig | 8 +++ drivers/iommu/Makefile | 1 + drivers/iommu/iommu-pasid.c | 53 +++++++++++++++++ drivers/iommu/iommu-pasid.h | 142 ++++++++++++++++++++++++++++++++++++++++++++ 4 files changed, 204 insertions(+) create mode 100644 drivers/iommu/iommu-pasid.c create mode 100644 drivers/iommu/iommu-pasid.h