From: Jason Gunthorpe <jgg@nvidia.com> mainline inclusion from mainline-v6.12-rc1 commit category: feature bugzilla: https://gitee.com/openeuler/kernel/issues/IB4WDJa2bb820e862d61f9ca1499e50091... CVE: NA Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i... -------------------------------- Since v5.12 the rbtree has gained some simplifying helpers aimed at making rb tree users write less convoluted boiler plate code. Instead the caller provides a single comparison function and the helpers generate the prior open-coded stuff. Update smmu->streams to use rb_find_add() and rb_find(). Tested-by: Nicolin Chen <nicolinc@nvidia.com> Reviewed-by: Mostafa Saleh <smostafa@google.com> Signed-off-by: Jason Gunthorpe <jgg@nvidia.com> Link: https://lore.kernel.org/r/1-v3-9fef8cdc2ff6+150d1-smmuv3_tidy_jgg@nvidia.com Signed-off-by: Will Deacon <will@kernel.org> Signed-off-by: Kunkun Jiang <jiangkunkun@huawei.com> --- drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 68 ++++++++++----------- 1 file changed, 31 insertions(+), 37 deletions(-) diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c index 5d17f52e3f8c..5cac4f67c98b 100644 --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c @@ -1915,26 +1915,37 @@ static int arm_smmu_init_l2_strtab(struct arm_smmu_device *smmu, u32 sid) return 0; } +static int arm_smmu_streams_cmp_key(const void *lhs, const struct rb_node *rhs) +{ + struct arm_smmu_stream *stream_rhs = + rb_entry(rhs, struct arm_smmu_stream, node); + const u32 *sid_lhs = lhs; + + if (*sid_lhs < stream_rhs->id) + return -1; + if (*sid_lhs > stream_rhs->id) + return 1; + return 0; +} + +static int arm_smmu_streams_cmp_node(struct rb_node *lhs, + const struct rb_node *rhs) +{ + return arm_smmu_streams_cmp_key( + &rb_entry(lhs, struct arm_smmu_stream, node)->id, rhs); +} + static struct arm_smmu_master * arm_smmu_find_master(struct arm_smmu_device *smmu, u32 sid) { struct rb_node *node; - struct arm_smmu_stream *stream; lockdep_assert_held(&smmu->streams_mutex); - node = smmu->streams.rb_node; - while (node) { - stream = rb_entry(node, struct arm_smmu_stream, node); - if (stream->id < sid) - node = node->rb_right; - else if (stream->id > sid) - node = node->rb_left; - else - return stream->master; - } - - return NULL; + node = rb_find(&sid, &smmu->streams, arm_smmu_streams_cmp_key); + if (!node) + return NULL; + return rb_entry(node, struct arm_smmu_stream, node)->master; } /* IRQ and event handlers */ @@ -3449,8 +3460,6 @@ static int arm_smmu_insert_master(struct arm_smmu_device *smmu, { int i; int ret = 0; - struct arm_smmu_stream *new_stream, *cur_stream; - struct rb_node **new_node, *parent_node = NULL; struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(master->dev); master->streams = kcalloc(fwspec->num_ids, sizeof(*master->streams), @@ -3461,9 +3470,9 @@ static int arm_smmu_insert_master(struct arm_smmu_device *smmu, mutex_lock(&smmu->streams_mutex); for (i = 0; i < fwspec->num_ids; i++) { + struct arm_smmu_stream *new_stream = &master->streams[i]; u32 sid = fwspec->ids[i]; - new_stream = &master->streams[i]; new_stream->id = sid; new_stream->master = master; @@ -3472,28 +3481,13 @@ static int arm_smmu_insert_master(struct arm_smmu_device *smmu, break; /* Insert into SID tree */ - new_node = &(smmu->streams.rb_node); - while (*new_node) { - cur_stream = rb_entry(*new_node, struct arm_smmu_stream, - node); - parent_node = *new_node; - if (cur_stream->id > new_stream->id) { - new_node = &((*new_node)->rb_left); - } else if (cur_stream->id < new_stream->id) { - new_node = &((*new_node)->rb_right); - } else { - dev_warn(master->dev, - "stream %u already in tree\n", - cur_stream->id); - ret = -EINVAL; - break; - } - } - if (ret) + if (rb_find_add(&new_stream->node, &smmu->streams, + arm_smmu_streams_cmp_node)) { + dev_warn(master->dev, "stream %u already in tree\n", + sid); + ret = -EINVAL; break; - - rb_link_node(&new_stream->node, parent_node, new_node); - rb_insert_color(&new_stream->node, &smmu->streams); + } } if (ret) { -- 2.33.0