Hi Baolu, On Thu, 26 Mar 2020 10:12:36 +0800 Lu Baolu <[email protected]> wrote:
> On 2020/3/26 1:55, Jacob Pan wrote: > > IOASID set defines a group of IDs that share the same token. The > > ioasid_set concept helps to do permission checking among users as > > in the current code. > > > > With guest SVA usage, each VM has its own IOASID set. More > > functionalities are needed: > > 1. Enforce quota, each guest may be assigned limited quota such > > that one guest cannot abuse all the system resource. > > 2. Stores IOASID mapping between guest and host IOASIDs > > 3. Per set operations, e.g. free the entire set > > > > For each ioasid_set token, a unique set ID is assigned. This makes > > reference of the set and data lookup much easier to implement. > > > > Signed-off-by: Liu Yi L <[email protected]> > > Signed-off-by: Jacob Pan <[email protected]> > > --- > > drivers/iommu/ioasid.c | 147 > > +++++++++++++++++++++++++++++++++++++++++++++++++ > > include/linux/ioasid.h | 13 +++++ 2 files changed, 160 > > insertions(+) > > > > diff --git a/drivers/iommu/ioasid.c b/drivers/iommu/ioasid.c > > index 4026e52855b9..27ee57f7079b 100644 > > --- a/drivers/iommu/ioasid.c > > +++ b/drivers/iommu/ioasid.c > > @@ -10,6 +10,25 @@ > > #include <linux/spinlock.h> > > #include <linux/xarray.h> > > > > +static DEFINE_XARRAY_ALLOC(ioasid_sets); > > +/** > > + * struct ioasid_set_data - Meta data about ioasid_set > > + * > > + * @token: Unique to identify an IOASID set > > + * @xa: XArray to store subset ID and IOASID mapping > > + * @size: Max number of IOASIDs can be allocated within the > > set > > + * @nr_ioasids Number of IOASIDs allocated in the set > > + * @sid ID of the set > > + */ > > +struct ioasid_set_data { > > + struct ioasid_set *token; > > + struct xarray xa; > > + int size; > > + int nr_ioasids; > > + int sid; > > + struct rcu_head rcu; > > +}; > > + > > struct ioasid_data { > > ioasid_t id; > > struct ioasid_set *set; > > @@ -388,6 +407,111 @@ void ioasid_free(ioasid_t ioasid) > > EXPORT_SYMBOL_GPL(ioasid_free); > > > > /** > > + * ioasid_alloc_set - Allocate a set of IOASIDs > > + * @token: Unique token of the IOASID set > > + * @quota: Quota allowed in this set > > + * @sid: IOASID set ID to be assigned > > + * > > + * Return 0 upon success. Token will be stored internally for > > lookup, > > + * IOASID allocation within the set and other per set operations > > will use > > + * the @sid assigned. > > + * > > + */ > > +int ioasid_alloc_set(struct ioasid_set *token, ioasid_t quota, int > > *sid) +{ > > + struct ioasid_set_data *sdata; > > + ioasid_t id; > > + int ret = 0; > > + > > + if (quota > ioasid_capacity_avail) { > > + pr_warn("Out of IOASID capacity! ask %d, avail > > %d\n", > > + quota, ioasid_capacity_avail); > > + return -ENOSPC; > > + } > > + > > + sdata = kzalloc(sizeof(*sdata), GFP_KERNEL); > > + if (!sdata) > > + return -ENOMEM; > > + > > + spin_lock(&ioasid_allocator_lock); > > + > > + ret = xa_alloc(&ioasid_sets, &id, sdata, > > + XA_LIMIT(0, ioasid_capacity_avail - quota), > > + GFP_KERNEL); > > + if (ret) { > > + kfree(sdata); > > + goto error; > > + } > > + > > + sdata->token = token; > > + sdata->size = quota; > > + sdata->sid = id; > > + > > + /* > > + * Set Xarray is used to store IDs within the set, get > > ready for > > + * sub-set ID and system-wide IOASID allocation results. > > + */ > > + xa_init_flags(&sdata->xa, XA_FLAGS_ALLOC); > > + > > + ioasid_capacity_avail -= quota; > > + *sid = id; > > + > > +error: > > + spin_unlock(&ioasid_allocator_lock); > > + > > + return ret; > > +} > > +EXPORT_SYMBOL_GPL(ioasid_alloc_set); > > + > > +/** > > + * ioasid_free_set - Free all IOASIDs within the set > > + * > > + * @sid: The IOASID set ID to be freed > > + * @destroy_set: Whether to keep the set for further > > allocation. > > + * If true, the set will be destroyed. > > + * > > + * All IOASIDs allocated within the set will be freed upon return. > > + */ > > +void ioasid_free_set(int sid, bool destroy_set) > > +{ > > + struct ioasid_set_data *sdata; > > + struct ioasid_data *entry; > > + unsigned long index; > > + > > + spin_lock(&ioasid_allocator_lock); > > + sdata = xa_load(&ioasid_sets, sid); > > + if (!sdata) { > > + pr_err("No IOASID set found to free %d\n", sid); > > + goto done_unlock; > > + } > > + > > + if (xa_empty(&sdata->xa)) { > > + pr_warn("No IOASIDs in the set %d\n", sdata->sid); > > + goto done_destroy; > > + } > > + > > + /* Just a place holder for now */ > > + xa_for_each(&sdata->xa, index, entry) { > > + /* Free from per sub-set pool */ > > + xa_erase(&sdata->xa, index); > > + } > > + > > +done_destroy: > > + if (destroy_set) { > > + xa_erase(&ioasid_sets, sid); > > + > > + /* Return the quota back to system pool */ > > + ioasid_capacity_avail += sdata->size; > > + kfree_rcu(sdata, rcu); > > + } > > + > > +done_unlock: > > + spin_unlock(&ioasid_allocator_lock); > > +} > > +EXPORT_SYMBOL_GPL(ioasid_free_set); > > + > > + > > +/** > > * ioasid_find - Find IOASID data > > * @set: the IOASID set > > * @ioasid: the IOASID to find > > @@ -431,6 +555,29 @@ void *ioasid_find(struct ioasid_set *set, > > ioasid_t ioasid, } > > EXPORT_SYMBOL_GPL(ioasid_find); > > > > +/** > > + * ioasid_find_sid - Retrieve IOASID set ID from an ioasid > > + * Caller must hold a reference to the set. > > + * > > + * @ioasid: IOASID associated with the set > > + * > > + * Return IOASID set ID or error > > + */ > > +int ioasid_find_sid(ioasid_t ioasid) > > +{ > > + struct ioasid_data *ioasid_data; > > + int ret = 0; > > + > > + spin_lock(&ioasid_allocator_lock); > > + ioasid_data = xa_load(&active_allocator->xa, ioasid); > > + ret = (ioasid_data) ? ioasid_data->sdata->sid : -ENOENT; > > + > > + spin_unlock(&ioasid_allocator_lock); > > + > > + return ret; > > +} > > +EXPORT_SYMBOL_GPL(ioasid_find_sid); > > + > > MODULE_AUTHOR("Jean-Philippe Brucker > > <[email protected]>"); MODULE_AUTHOR("Jacob Pan > > <[email protected]>"); MODULE_DESCRIPTION("IO Address > > Space ID (IOASID) allocator"); diff --git a/include/linux/ioasid.h > > b/include/linux/ioasid.h index 9711fa0dc357..be158e03c034 100644 > > --- a/include/linux/ioasid.h > > +++ b/include/linux/ioasid.h > > @@ -41,6 +41,9 @@ int ioasid_register_allocator(struct > > ioasid_allocator_ops *allocator); void > > ioasid_unregister_allocator(struct ioasid_allocator_ops > > *allocator); int ioasid_set_data(ioasid_t ioasid, void *data); void > > ioasid_install_capacity(ioasid_t total); +int > > ioasid_alloc_set(struct ioasid_set *token, ioasid_t quota, int > > *sid); +void ioasid_free_set(int sid, bool destroy_set); +int > > ioasid_find_sid(ioasid_t ioasid); #else /* !CONFIG_IOASID */ > > static inline ioasid_t ioasid_alloc(struct ioasid_set *set, > > ioasid_t min, ioasid_t max, void *private) > > @@ -52,6 +55,15 @@ static inline void ioasid_free(ioasid_t ioasid) > > { > > } > > > > +static inline int ioasid_alloc_set(struct ioasid_set *token, > > ioasid_t quota, int *sid) +{ > > + return -ENOTSUPP; > > +} > > + > > +static inline void ioasid_free_set(int sid, bool destroy_set) > > +{ > > +} > > + > > static inline int ioasid_find_sid(ioasid_t ioasid) > { > return INVALID_IOASID; > } > Good catch, will add to the next version. > Best regards, > baolu > > > static inline void *ioasid_find(struct ioasid_set *set, ioasid_t > > ioasid, bool (*getter)(void *)) > > { > > @@ -75,5 +87,6 @@ static inline int ioasid_set_data(ioasid_t > > ioasid, void *data) static inline void > > ioasid_install_capacity(ioasid_t total) { > > } > > + > > #endif /* CONFIG_IOASID */ > > #endif /* __LINUX_IOASID_H */ > > [Jacob Pan] _______________________________________________ iommu mailing list [email protected] https://lists.linuxfoundation.org/mailman/listinfo/iommu
