Messages in this thread Patch in this message | | | From | Jacob Pan <> | Subject | [PATCH 09/10] iommu/ioasid: Support ioasid_set quota adjustment | Date | Wed, 25 Mar 2020 10:55:30 -0700 |
| |
IOASID set is allocated with an initial quota, at runtime there may be needs to balance IOASID resources among different VMs/sets.
This patch adds a new API to adjust per set quota.
Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com> --- drivers/iommu/ioasid.c | 44 ++++++++++++++++++++++++++++++++++++++++++++ include/linux/ioasid.h | 6 ++++++ 2 files changed, 50 insertions(+)
diff --git a/drivers/iommu/ioasid.c b/drivers/iommu/ioasid.c index 27dce2cb5af2..5ac28862a1db 100644 --- a/drivers/iommu/ioasid.c +++ b/drivers/iommu/ioasid.c @@ -578,6 +578,50 @@ void ioasid_free_set(int sid, bool destroy_set) } EXPORT_SYMBOL_GPL(ioasid_free_set); +/** + * ioasid_adjust_set - Adjust the quota of an IOASID set + * @quota: Quota allowed in this set + * @sid: IOASID set ID to be assigned + * + * Return 0 on success. If the new quota is smaller than the number of + * IOASIDs already allocated, -EINVAL will be returned. No change will be + * made to the existing quota. + */ +int ioasid_adjust_set(int sid, int quota) +{ + struct ioasid_set_data *sdata; + int ret = 0; + + mutex_lock(&ioasid_allocator_lock); + sdata = xa_load(&ioasid_sets, sid); + if (!sdata || sdata->nr_ioasids > quota) { + pr_err("Failed to adjust IOASID set %d quota %d\n", + sid, quota); + ret = -EINVAL; + goto done_unlock; + } + + if (quota >= ioasid_capacity_avail) { + ret = -ENOSPC; + goto done_unlock; + } + + /* Return the delta back to system pool */ + ioasid_capacity_avail += sdata->size - quota; + + /* + * May have a policy to prevent giving all available IOASIDs + * to one set. But we don't enforce here, it should be in the + * upper layers. + */ + sdata->size = quota; + +done_unlock: + mutex_unlock(&ioasid_allocator_lock); + + return ret; +} +EXPORT_SYMBOL_GPL(ioasid_adjust_set); /** * ioasid_find - Find IOASID data diff --git a/include/linux/ioasid.h b/include/linux/ioasid.h index 32d032913828..6e7de6fb91bf 100644 --- a/include/linux/ioasid.h +++ b/include/linux/ioasid.h @@ -73,6 +73,7 @@ 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); int ioasid_notify(ioasid_t id, enum ioasid_notify_val cmd); +int ioasid_adjust_set(int sid, int quota); #else /* !CONFIG_IOASID */ static inline ioasid_t ioasid_alloc(int sid, ioasid_t min, @@ -136,5 +137,10 @@ static inline int ioasid_alloc_system_set(int quota) return -ENOTSUPP; } +static inline int ioasid_adjust_set(int sid, int quota) +{ + return -ENOTSUPP; +} + #endif /* CONFIG_IOASID */ #endif /* __LINUX_IOASID_H */ -- 2.7.4
| |