[PATCH v6 09/18] treewide: Change list_sort to use const pointers

From: Sami Tolvanen
Date: Thu Apr 08 2021 - 14:29:55 EST


list_sort() internally casts the comparison function passed to it
to a different type with constant struct list_head pointers, and
uses this pointer to call the functions, which trips indirect call
Control-Flow Integrity (CFI) checking.

Instead of removing the consts, this change defines the
list_cmp_func_t type and changes the comparison function types of
all list_sort() callers to use const pointers, thus avoiding type
mismatches.

Suggested-by: Nick Desaulniers <ndesaulniers@xxxxxxxxxx>
Signed-off-by: Sami Tolvanen <samitolvanen@xxxxxxxxxx>
Reviewed-by: Nick Desaulniers <ndesaulniers@xxxxxxxxxx>
Reviewed-by: Christoph Hellwig <hch@xxxxxx>
Reviewed-by: Kees Cook <keescook@xxxxxxxxxxxx>
Tested-by: Nick Desaulniers <ndesaulniers@xxxxxxxxxx>
Tested-by: Nathan Chancellor <nathan@xxxxxxxxxx>
---
arch/arm64/kvm/vgic/vgic-its.c | 8 ++++----
arch/arm64/kvm/vgic/vgic.c | 3 ++-
block/blk-mq-sched.c | 3 ++-
block/blk-mq.c | 3 ++-
drivers/acpi/nfit/core.c | 3 ++-
drivers/acpi/numa/hmat.c | 3 ++-
drivers/clk/keystone/sci-clk.c | 4 ++--
drivers/gpu/drm/drm_modes.c | 3 ++-
drivers/gpu/drm/i915/gt/intel_engine_user.c | 3 ++-
drivers/gpu/drm/i915/gvt/debugfs.c | 2 +-
drivers/gpu/drm/i915/selftests/i915_gem_gtt.c | 3 ++-
drivers/gpu/drm/radeon/radeon_cs.c | 4 ++--
.../hw/usnic/usnic_uiom_interval_tree.c | 3 ++-
drivers/interconnect/qcom/bcm-voter.c | 2 +-
drivers/md/raid5.c | 3 ++-
drivers/misc/sram.c | 4 ++--
drivers/nvme/host/core.c | 3 ++-
.../pci/controller/cadence/pcie-cadence-host.c | 3 ++-
drivers/spi/spi-loopback-test.c | 3 ++-
fs/btrfs/raid56.c | 3 ++-
fs/btrfs/tree-log.c | 3 ++-
fs/btrfs/volumes.c | 3 ++-
fs/ext4/fsmap.c | 4 ++--
fs/gfs2/glock.c | 3 ++-
fs/gfs2/log.c | 2 +-
fs/gfs2/lops.c | 3 ++-
fs/iomap/buffered-io.c | 3 ++-
fs/ubifs/gc.c | 7 ++++---
fs/ubifs/replay.c | 4 ++--
fs/xfs/scrub/bitmap.c | 4 ++--
fs/xfs/xfs_bmap_item.c | 4 ++--
fs/xfs/xfs_buf.c | 6 +++---
fs/xfs/xfs_extent_busy.c | 4 ++--
fs/xfs/xfs_extent_busy.h | 3 ++-
fs/xfs/xfs_extfree_item.c | 4 ++--
fs/xfs/xfs_refcount_item.c | 4 ++--
fs/xfs/xfs_rmap_item.c | 4 ++--
include/linux/list_sort.h | 7 ++++---
lib/list_sort.c | 17 ++++++-----------
lib/test_list_sort.c | 3 ++-
net/tipc/name_table.c | 4 ++--
41 files changed, 90 insertions(+), 72 deletions(-)

diff --git a/arch/arm64/kvm/vgic/vgic-its.c b/arch/arm64/kvm/vgic/vgic-its.c
index 40cbaca81333..b9518f94bd43 100644
--- a/arch/arm64/kvm/vgic/vgic-its.c
+++ b/arch/arm64/kvm/vgic/vgic-its.c
@@ -2190,8 +2190,8 @@ static int vgic_its_restore_ite(struct vgic_its *its, u32 event_id,
return offset;
}

-static int vgic_its_ite_cmp(void *priv, struct list_head *a,
- struct list_head *b)
+static int vgic_its_ite_cmp(void *priv, const struct list_head *a,
+ const struct list_head *b)
{
struct its_ite *itea = container_of(a, struct its_ite, ite_list);
struct its_ite *iteb = container_of(b, struct its_ite, ite_list);
@@ -2329,8 +2329,8 @@ static int vgic_its_restore_dte(struct vgic_its *its, u32 id,
return offset;
}

-static int vgic_its_device_cmp(void *priv, struct list_head *a,
- struct list_head *b)
+static int vgic_its_device_cmp(void *priv, const struct list_head *a,
+ const struct list_head *b)
{
struct its_device *deva = container_of(a, struct its_device, dev_list);
struct its_device *devb = container_of(b, struct its_device, dev_list);
diff --git a/arch/arm64/kvm/vgic/vgic.c b/arch/arm64/kvm/vgic/vgic.c
index 1c597c9885fa..15b666200f0b 100644
--- a/arch/arm64/kvm/vgic/vgic.c
+++ b/arch/arm64/kvm/vgic/vgic.c
@@ -255,7 +255,8 @@ static struct kvm_vcpu *vgic_target_oracle(struct vgic_irq *irq)
* Return negative if "a" sorts before "b", 0 to preserve order, and positive
* to sort "b" before "a".
*/
-static int vgic_irq_cmp(void *priv, struct list_head *a, struct list_head *b)
+static int vgic_irq_cmp(void *priv, const struct list_head *a,
+ const struct list_head *b)
{
struct vgic_irq *irqa = container_of(a, struct vgic_irq, ap_list);
struct vgic_irq *irqb = container_of(b, struct vgic_irq, ap_list);
diff --git a/block/blk-mq-sched.c b/block/blk-mq-sched.c
index e1e997af89a0..3ebd6f10f728 100644
--- a/block/blk-mq-sched.c
+++ b/block/blk-mq-sched.c
@@ -75,7 +75,8 @@ void blk_mq_sched_restart(struct blk_mq_hw_ctx *hctx)
blk_mq_run_hw_queue(hctx, true);
}

-static int sched_rq_cmp(void *priv, struct list_head *a, struct list_head *b)
+static int sched_rq_cmp(void *priv, const struct list_head *a,
+ const struct list_head *b)
{
struct request *rqa = container_of(a, struct request, queuelist);
struct request *rqb = container_of(b, struct request, queuelist);
diff --git a/block/blk-mq.c b/block/blk-mq.c
index d4d7c1caa439..4e3a70ab5be1 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -1895,7 +1895,8 @@ void blk_mq_insert_requests(struct blk_mq_hw_ctx *hctx, struct blk_mq_ctx *ctx,
spin_unlock(&ctx->lock);
}

-static int plug_rq_cmp(void *priv, struct list_head *a, struct list_head *b)
+static int plug_rq_cmp(void *priv, const struct list_head *a,
+ const struct list_head *b)
{
struct request *rqa = container_of(a, struct request, queuelist);
struct request *rqb = container_of(b, struct request, queuelist);
diff --git a/drivers/acpi/nfit/core.c b/drivers/acpi/nfit/core.c
index 8c5dde628405..d15e3ee93b5b 100644
--- a/drivers/acpi/nfit/core.c
+++ b/drivers/acpi/nfit/core.c
@@ -1195,7 +1195,8 @@ static int __nfit_mem_init(struct acpi_nfit_desc *acpi_desc,
return 0;
}

-static int nfit_mem_cmp(void *priv, struct list_head *_a, struct list_head *_b)
+static int nfit_mem_cmp(void *priv, const struct list_head *_a,
+ const struct list_head *_b)
{
struct nfit_mem *a = container_of(_a, typeof(*a), list);
struct nfit_mem *b = container_of(_b, typeof(*b), list);
diff --git a/drivers/acpi/numa/hmat.c b/drivers/acpi/numa/hmat.c
index cb73a5d6ea76..137a5dd880c2 100644
--- a/drivers/acpi/numa/hmat.c
+++ b/drivers/acpi/numa/hmat.c
@@ -558,7 +558,8 @@ static bool hmat_update_best(u8 type, u32 value, u32 *best)
return updated;
}

-static int initiator_cmp(void *priv, struct list_head *a, struct list_head *b)
+static int initiator_cmp(void *priv, const struct list_head *a,
+ const struct list_head *b)
{
struct memory_initiator *ia;
struct memory_initiator *ib;
diff --git a/drivers/clk/keystone/sci-clk.c b/drivers/clk/keystone/sci-clk.c
index aaf31abe1c8f..7e1b136e71ae 100644
--- a/drivers/clk/keystone/sci-clk.c
+++ b/drivers/clk/keystone/sci-clk.c
@@ -503,8 +503,8 @@ static int ti_sci_scan_clocks_from_fw(struct sci_clk_provider *provider)

#else

-static int _cmp_sci_clk_list(void *priv, struct list_head *a,
- struct list_head *b)
+static int _cmp_sci_clk_list(void *priv, const struct list_head *a,
+ const struct list_head *b)
{
struct sci_clk *ca = container_of(a, struct sci_clk, node);
struct sci_clk *cb = container_of(b, struct sci_clk, node);
diff --git a/drivers/gpu/drm/drm_modes.c b/drivers/gpu/drm/drm_modes.c
index 1ac67d4505e0..6662d0457ad6 100644
--- a/drivers/gpu/drm/drm_modes.c
+++ b/drivers/gpu/drm/drm_modes.c
@@ -1290,7 +1290,8 @@ EXPORT_SYMBOL(drm_mode_prune_invalid);
* Negative if @lh_a is better than @lh_b, zero if they're equivalent, or
* positive if @lh_b is better than @lh_a.
*/
-static int drm_mode_compare(void *priv, struct list_head *lh_a, struct list_head *lh_b)
+static int drm_mode_compare(void *priv, const struct list_head *lh_a,
+ const struct list_head *lh_b)
{
struct drm_display_mode *a = list_entry(lh_a, struct drm_display_mode, head);
struct drm_display_mode *b = list_entry(lh_b, struct drm_display_mode, head);
diff --git a/drivers/gpu/drm/i915/gt/intel_engine_user.c b/drivers/gpu/drm/i915/gt/intel_engine_user.c
index 34e6096f196e..da21d2a10cc9 100644
--- a/drivers/gpu/drm/i915/gt/intel_engine_user.c
+++ b/drivers/gpu/drm/i915/gt/intel_engine_user.c
@@ -49,7 +49,8 @@ static const u8 uabi_classes[] = {
[VIDEO_ENHANCEMENT_CLASS] = I915_ENGINE_CLASS_VIDEO_ENHANCE,
};

-static int engine_cmp(void *priv, struct list_head *A, struct list_head *B)
+static int engine_cmp(void *priv, const struct list_head *A,
+ const struct list_head *B)
{
const struct intel_engine_cs *a =
container_of((struct rb_node *)A, typeof(*a), uabi_node);
diff --git a/drivers/gpu/drm/i915/gvt/debugfs.c b/drivers/gpu/drm/i915/gvt/debugfs.c
index 62e6a14ad58e..9f1c209d9251 100644
--- a/drivers/gpu/drm/i915/gvt/debugfs.c
+++ b/drivers/gpu/drm/i915/gvt/debugfs.c
@@ -41,7 +41,7 @@ struct diff_mmio {

/* Compare two diff_mmio items. */
static int mmio_offset_compare(void *priv,
- struct list_head *a, struct list_head *b)
+ const struct list_head *a, const struct list_head *b)
{
struct diff_mmio *ma;
struct diff_mmio *mb;
diff --git a/drivers/gpu/drm/i915/selftests/i915_gem_gtt.c b/drivers/gpu/drm/i915/selftests/i915_gem_gtt.c
index c1adea8765a9..52b9c39e0155 100644
--- a/drivers/gpu/drm/i915/selftests/i915_gem_gtt.c
+++ b/drivers/gpu/drm/i915/selftests/i915_gem_gtt.c
@@ -1076,7 +1076,8 @@ static int igt_ppgtt_shrink_boom(void *arg)
return exercise_ppgtt(arg, shrink_boom);
}

-static int sort_holes(void *priv, struct list_head *A, struct list_head *B)
+static int sort_holes(void *priv, const struct list_head *A,
+ const struct list_head *B)
{
struct drm_mm_node *a = list_entry(A, typeof(*a), hole_stack);
struct drm_mm_node *b = list_entry(B, typeof(*b), hole_stack);
diff --git a/drivers/gpu/drm/radeon/radeon_cs.c b/drivers/gpu/drm/radeon/radeon_cs.c
index 35e937d39b51..1a5c3db1d53b 100644
--- a/drivers/gpu/drm/radeon/radeon_cs.c
+++ b/drivers/gpu/drm/radeon/radeon_cs.c
@@ -393,8 +393,8 @@ int radeon_cs_parser_init(struct radeon_cs_parser *p, void *data)
return 0;
}

-static int cmp_size_smaller_first(void *priv, struct list_head *a,
- struct list_head *b)
+static int cmp_size_smaller_first(void *priv, const struct list_head *a,
+ const struct list_head *b)
{
struct radeon_bo_list *la = list_entry(a, struct radeon_bo_list, tv.head);
struct radeon_bo_list *lb = list_entry(b, struct radeon_bo_list, tv.head);
diff --git a/drivers/infiniband/hw/usnic/usnic_uiom_interval_tree.c b/drivers/infiniband/hw/usnic/usnic_uiom_interval_tree.c
index d399523206c7..29d71267af78 100644
--- a/drivers/infiniband/hw/usnic/usnic_uiom_interval_tree.c
+++ b/drivers/infiniband/hw/usnic/usnic_uiom_interval_tree.c
@@ -83,7 +83,8 @@ usnic_uiom_interval_node_alloc(long int start, long int last, int ref_cnt,
return interval;
}

-static int interval_cmp(void *priv, struct list_head *a, struct list_head *b)
+static int interval_cmp(void *priv, const struct list_head *a,
+ const struct list_head *b)
{
struct usnic_uiom_interval_node *node_a, *node_b;

diff --git a/drivers/interconnect/qcom/bcm-voter.c b/drivers/interconnect/qcom/bcm-voter.c
index 1cc565bce2f4..d1591a28b743 100644
--- a/drivers/interconnect/qcom/bcm-voter.c
+++ b/drivers/interconnect/qcom/bcm-voter.c
@@ -39,7 +39,7 @@ struct bcm_voter {
u32 tcs_wait;
};

-static int cmp_vcd(void *priv, struct list_head *a, struct list_head *b)
+static int cmp_vcd(void *priv, const struct list_head *a, const struct list_head *b)
{
const struct qcom_icc_bcm *bcm_a = list_entry(a, struct qcom_icc_bcm, list);
const struct qcom_icc_bcm *bcm_b = list_entry(b, struct qcom_icc_bcm, list);
diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c
index 5d57a5bd171f..841e1c1aa5e6 100644
--- a/drivers/md/raid5.c
+++ b/drivers/md/raid5.c
@@ -953,7 +953,8 @@ static void dispatch_bio_list(struct bio_list *tmp)
submit_bio_noacct(bio);
}

-static int cmp_stripe(void *priv, struct list_head *a, struct list_head *b)
+static int cmp_stripe(void *priv, const struct list_head *a,
+ const struct list_head *b)
{
const struct r5pending_data *da = list_entry(a,
struct r5pending_data, sibling);
diff --git a/drivers/misc/sram.c b/drivers/misc/sram.c
index 6c1a23cb3e8c..202bf951e909 100644
--- a/drivers/misc/sram.c
+++ b/drivers/misc/sram.c
@@ -144,8 +144,8 @@ static void sram_free_partitions(struct sram_dev *sram)
}
}

-static int sram_reserve_cmp(void *priv, struct list_head *a,
- struct list_head *b)
+static int sram_reserve_cmp(void *priv, const struct list_head *a,
+ const struct list_head *b)
{
struct sram_reserve *ra = list_entry(a, struct sram_reserve, list);
struct sram_reserve *rb = list_entry(b, struct sram_reserve, list);
diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c
index 0896e21642be..5eaaa51a5e30 100644
--- a/drivers/nvme/host/core.c
+++ b/drivers/nvme/host/core.c
@@ -3855,7 +3855,8 @@ static int nvme_init_ns_head(struct nvme_ns *ns, unsigned nsid,
return ret;
}

-static int ns_cmp(void *priv, struct list_head *a, struct list_head *b)
+static int ns_cmp(void *priv, const struct list_head *a,
+ const struct list_head *b)
{
struct nvme_ns *nsa = container_of(a, struct nvme_ns, list);
struct nvme_ns *nsb = container_of(b, struct nvme_ns, list);
diff --git a/drivers/pci/controller/cadence/pcie-cadence-host.c b/drivers/pci/controller/cadence/pcie-cadence-host.c
index 73dcf8cf98fb..ae1c55503513 100644
--- a/drivers/pci/controller/cadence/pcie-cadence-host.c
+++ b/drivers/pci/controller/cadence/pcie-cadence-host.c
@@ -345,7 +345,8 @@ static int cdns_pcie_host_bar_config(struct cdns_pcie_rc *rc,
return 0;
}

-static int cdns_pcie_host_dma_ranges_cmp(void *priv, struct list_head *a, struct list_head *b)
+static int cdns_pcie_host_dma_ranges_cmp(void *priv, const struct list_head *a,
+ const struct list_head *b)
{
struct resource_entry *entry1, *entry2;

diff --git a/drivers/spi/spi-loopback-test.c b/drivers/spi/spi-loopback-test.c
index df981e55c24c..f1cf2232f0b5 100644
--- a/drivers/spi/spi-loopback-test.c
+++ b/drivers/spi/spi-loopback-test.c
@@ -454,7 +454,8 @@ struct rx_ranges {
u8 *end;
};

-static int rx_ranges_cmp(void *priv, struct list_head *a, struct list_head *b)
+static int rx_ranges_cmp(void *priv, const struct list_head *a,
+ const struct list_head *b)
{
struct rx_ranges *rx_a = list_entry(a, struct rx_ranges, list);
struct rx_ranges *rx_b = list_entry(b, struct rx_ranges, list);
diff --git a/fs/btrfs/raid56.c b/fs/btrfs/raid56.c
index 8c31357f08ed..f4139de63b2e 100644
--- a/fs/btrfs/raid56.c
+++ b/fs/btrfs/raid56.c
@@ -1634,7 +1634,8 @@ struct btrfs_plug_cb {
/*
* rbios on the plug list are sorted for easier merging.
*/
-static int plug_cmp(void *priv, struct list_head *a, struct list_head *b)
+static int plug_cmp(void *priv, const struct list_head *a,
+ const struct list_head *b)
{
struct btrfs_raid_bio *ra = container_of(a, struct btrfs_raid_bio,
plug_list);
diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c
index 92a368627791..00a88bd8105e 100644
--- a/fs/btrfs/tree-log.c
+++ b/fs/btrfs/tree-log.c
@@ -4136,7 +4136,8 @@ static noinline int copy_items(struct btrfs_trans_handle *trans,
return ret;
}

-static int extent_cmp(void *priv, struct list_head *a, struct list_head *b)
+static int extent_cmp(void *priv, const struct list_head *a,
+ const struct list_head *b)
{
struct extent_map *em1, *em2;

diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index 1c6810bbaf8b..912dd8b9f156 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -1224,7 +1224,8 @@ static int open_fs_devices(struct btrfs_fs_devices *fs_devices,
return 0;
}

-static int devid_cmp(void *priv, struct list_head *a, struct list_head *b)
+static int devid_cmp(void *priv, const struct list_head *a,
+ const struct list_head *b)
{
struct btrfs_device *dev1, *dev2;

diff --git a/fs/ext4/fsmap.c b/fs/ext4/fsmap.c
index 4c2a9fe30067..4493ef0c715e 100644
--- a/fs/ext4/fsmap.c
+++ b/fs/ext4/fsmap.c
@@ -354,8 +354,8 @@ static unsigned int ext4_getfsmap_find_sb(struct super_block *sb,

/* Compare two fsmap items. */
static int ext4_getfsmap_compare(void *priv,
- struct list_head *a,
- struct list_head *b)
+ const struct list_head *a,
+ const struct list_head *b)
{
struct ext4_fsmap *fa;
struct ext4_fsmap *fb;
diff --git a/fs/gfs2/glock.c b/fs/gfs2/glock.c
index 9567520d79f7..c06a6cdf05de 100644
--- a/fs/gfs2/glock.c
+++ b/fs/gfs2/glock.c
@@ -1732,7 +1732,8 @@ void gfs2_glock_complete(struct gfs2_glock *gl, int ret)
spin_unlock(&gl->gl_lockref.lock);
}

-static int glock_cmp(void *priv, struct list_head *a, struct list_head *b)
+static int glock_cmp(void *priv, const struct list_head *a,
+ const struct list_head *b)
{
struct gfs2_glock *gla, *glb;

diff --git a/fs/gfs2/log.c b/fs/gfs2/log.c
index 6410281546f9..88649b43fcff 100644
--- a/fs/gfs2/log.c
+++ b/fs/gfs2/log.c
@@ -695,7 +695,7 @@ void log_flush_wait(struct gfs2_sbd *sdp)
}
}

-static int ip_cmp(void *priv, struct list_head *a, struct list_head *b)
+static int ip_cmp(void *priv, const struct list_head *a, const struct list_head *b)
{
struct gfs2_inode *ipa, *ipb;

diff --git a/fs/gfs2/lops.c b/fs/gfs2/lops.c
index a82f4747aa8d..b4809967efc6 100644
--- a/fs/gfs2/lops.c
+++ b/fs/gfs2/lops.c
@@ -634,7 +634,8 @@ static void gfs2_check_magic(struct buffer_head *bh)
kunmap_atomic(kaddr);
}

-static int blocknr_cmp(void *priv, struct list_head *a, struct list_head *b)
+static int blocknr_cmp(void *priv, const struct list_head *a,
+ const struct list_head *b)
{
struct gfs2_bufdata *bda, *bdb;

diff --git a/fs/iomap/buffered-io.c b/fs/iomap/buffered-io.c
index 414769a6ad11..0129e6bab985 100644
--- a/fs/iomap/buffered-io.c
+++ b/fs/iomap/buffered-io.c
@@ -1155,7 +1155,8 @@ iomap_ioend_try_merge(struct iomap_ioend *ioend, struct list_head *more_ioends,
EXPORT_SYMBOL_GPL(iomap_ioend_try_merge);

static int
-iomap_ioend_compare(void *priv, struct list_head *a, struct list_head *b)
+iomap_ioend_compare(void *priv, const struct list_head *a,
+ const struct list_head *b)
{
struct iomap_ioend *ia = container_of(a, struct iomap_ioend, io_list);
struct iomap_ioend *ib = container_of(b, struct iomap_ioend, io_list);
diff --git a/fs/ubifs/gc.c b/fs/ubifs/gc.c
index a4aaeea63893..dc3e26e9ed7b 100644
--- a/fs/ubifs/gc.c
+++ b/fs/ubifs/gc.c
@@ -102,7 +102,8 @@ static int switch_gc_head(struct ubifs_info *c)
* This function compares data nodes @a and @b. Returns %1 if @a has greater
* inode or block number, and %-1 otherwise.
*/
-static int data_nodes_cmp(void *priv, struct list_head *a, struct list_head *b)
+static int data_nodes_cmp(void *priv, const struct list_head *a,
+ const struct list_head *b)
{
ino_t inuma, inumb;
struct ubifs_info *c = priv;
@@ -145,8 +146,8 @@ static int data_nodes_cmp(void *priv, struct list_head *a, struct list_head *b)
* first and sorted by length in descending order. Directory entry nodes go
* after inode nodes and are sorted in ascending hash valuer order.
*/
-static int nondata_nodes_cmp(void *priv, struct list_head *a,
- struct list_head *b)
+static int nondata_nodes_cmp(void *priv, const struct list_head *a,
+ const struct list_head *b)
{
ino_t inuma, inumb;
struct ubifs_info *c = priv;
diff --git a/fs/ubifs/replay.c b/fs/ubifs/replay.c
index 0f8a6a16421b..4d17e5382b74 100644
--- a/fs/ubifs/replay.c
+++ b/fs/ubifs/replay.c
@@ -298,8 +298,8 @@ static int apply_replay_entry(struct ubifs_info *c, struct replay_entry *r)
* entries @a and @b by comparing their sequence numer. Returns %1 if @a has
* greater sequence number and %-1 otherwise.
*/
-static int replay_entries_cmp(void *priv, struct list_head *a,
- struct list_head *b)
+static int replay_entries_cmp(void *priv, const struct list_head *a,
+ const struct list_head *b)
{
struct ubifs_info *c = priv;
struct replay_entry *ra, *rb;
diff --git a/fs/xfs/scrub/bitmap.c b/fs/xfs/scrub/bitmap.c
index f88694f22d05..813b5f219113 100644
--- a/fs/xfs/scrub/bitmap.c
+++ b/fs/xfs/scrub/bitmap.c
@@ -63,8 +63,8 @@ xbitmap_init(
static int
xbitmap_range_cmp(
void *priv,
- struct list_head *a,
- struct list_head *b)
+ const struct list_head *a,
+ const struct list_head *b)
{
struct xbitmap_range *ap;
struct xbitmap_range *bp;
diff --git a/fs/xfs/xfs_bmap_item.c b/fs/xfs/xfs_bmap_item.c
index 2344757ede63..e3a691937e92 100644
--- a/fs/xfs/xfs_bmap_item.c
+++ b/fs/xfs/xfs_bmap_item.c
@@ -265,8 +265,8 @@ xfs_trans_log_finish_bmap_update(
static int
xfs_bmap_update_diff_items(
void *priv,
- struct list_head *a,
- struct list_head *b)
+ const struct list_head *a,
+ const struct list_head *b)
{
struct xfs_bmap_intent *ba;
struct xfs_bmap_intent *bb;
diff --git a/fs/xfs/xfs_buf.c b/fs/xfs/xfs_buf.c
index 37a1d12762d8..592800c8852f 100644
--- a/fs/xfs/xfs_buf.c
+++ b/fs/xfs/xfs_buf.c
@@ -2124,9 +2124,9 @@ xfs_buf_delwri_queue(
*/
static int
xfs_buf_cmp(
- void *priv,
- struct list_head *a,
- struct list_head *b)
+ void *priv,
+ const struct list_head *a,
+ const struct list_head *b)
{
struct xfs_buf *ap = container_of(a, struct xfs_buf, b_list);
struct xfs_buf *bp = container_of(b, struct xfs_buf, b_list);
diff --git a/fs/xfs/xfs_extent_busy.c b/fs/xfs/xfs_extent_busy.c
index ef17c1f6db32..a4075685d9eb 100644
--- a/fs/xfs/xfs_extent_busy.c
+++ b/fs/xfs/xfs_extent_busy.c
@@ -629,8 +629,8 @@ xfs_extent_busy_wait_all(
int
xfs_extent_busy_ag_cmp(
void *priv,
- struct list_head *l1,
- struct list_head *l2)
+ const struct list_head *l1,
+ const struct list_head *l2)
{
struct xfs_extent_busy *b1 =
container_of(l1, struct xfs_extent_busy, list);
diff --git a/fs/xfs/xfs_extent_busy.h b/fs/xfs/xfs_extent_busy.h
index 990ab3891971..8aea07100092 100644
--- a/fs/xfs/xfs_extent_busy.h
+++ b/fs/xfs/xfs_extent_busy.h
@@ -58,7 +58,8 @@ void
xfs_extent_busy_wait_all(struct xfs_mount *mp);

int
-xfs_extent_busy_ag_cmp(void *priv, struct list_head *a, struct list_head *b);
+xfs_extent_busy_ag_cmp(void *priv, const struct list_head *a,
+ const struct list_head *b);

static inline void xfs_extent_busy_sort(struct list_head *list)
{
diff --git a/fs/xfs/xfs_extfree_item.c b/fs/xfs/xfs_extfree_item.c
index 93223ebb3372..2424230ca2c3 100644
--- a/fs/xfs/xfs_extfree_item.c
+++ b/fs/xfs/xfs_extfree_item.c
@@ -397,8 +397,8 @@ xfs_trans_free_extent(
static int
xfs_extent_free_diff_items(
void *priv,
- struct list_head *a,
- struct list_head *b)
+ const struct list_head *a,
+ const struct list_head *b)
{
struct xfs_mount *mp = priv;
struct xfs_extent_free_item *ra;
diff --git a/fs/xfs/xfs_refcount_item.c b/fs/xfs/xfs_refcount_item.c
index 07ebccbbf4df..746f4eda724c 100644
--- a/fs/xfs/xfs_refcount_item.c
+++ b/fs/xfs/xfs_refcount_item.c
@@ -269,8 +269,8 @@ xfs_trans_log_finish_refcount_update(
static int
xfs_refcount_update_diff_items(
void *priv,
- struct list_head *a,
- struct list_head *b)
+ const struct list_head *a,
+ const struct list_head *b)
{
struct xfs_mount *mp = priv;
struct xfs_refcount_intent *ra;
diff --git a/fs/xfs/xfs_rmap_item.c b/fs/xfs/xfs_rmap_item.c
index 49cebd68b672..dc4f0c9f0897 100644
--- a/fs/xfs/xfs_rmap_item.c
+++ b/fs/xfs/xfs_rmap_item.c
@@ -337,8 +337,8 @@ xfs_trans_log_finish_rmap_update(
static int
xfs_rmap_update_diff_items(
void *priv,
- struct list_head *a,
- struct list_head *b)
+ const struct list_head *a,
+ const struct list_head *b)
{
struct xfs_mount *mp = priv;
struct xfs_rmap_intent *ra;
diff --git a/include/linux/list_sort.h b/include/linux/list_sort.h
index 20f178c24e9d..453105f74e05 100644
--- a/include/linux/list_sort.h
+++ b/include/linux/list_sort.h
@@ -6,8 +6,9 @@

struct list_head;

+typedef int __attribute__((nonnull(2,3))) (*list_cmp_func_t)(void *,
+ const struct list_head *, const struct list_head *);
+
__attribute__((nonnull(2,3)))
-void list_sort(void *priv, struct list_head *head,
- int (*cmp)(void *priv, struct list_head *a,
- struct list_head *b));
+void list_sort(void *priv, struct list_head *head, list_cmp_func_t cmp);
#endif
diff --git a/lib/list_sort.c b/lib/list_sort.c
index 52f0c258c895..a926d96ffd44 100644
--- a/lib/list_sort.c
+++ b/lib/list_sort.c
@@ -7,16 +7,13 @@
#include <linux/list_sort.h>
#include <linux/list.h>

-typedef int __attribute__((nonnull(2,3))) (*cmp_func)(void *,
- struct list_head const *, struct list_head const *);
-
/*
* Returns a list organized in an intermediate format suited
* to chaining of merge() calls: null-terminated, no reserved or
* sentinel head node, "prev" links not maintained.
*/
__attribute__((nonnull(2,3,4)))
-static struct list_head *merge(void *priv, cmp_func cmp,
+static struct list_head *merge(void *priv, list_cmp_func_t cmp,
struct list_head *a, struct list_head *b)
{
struct list_head *head, **tail = &head;
@@ -52,7 +49,7 @@ static struct list_head *merge(void *priv, cmp_func cmp,
* throughout.
*/
__attribute__((nonnull(2,3,4,5)))
-static void merge_final(void *priv, cmp_func cmp, struct list_head *head,
+static void merge_final(void *priv, list_cmp_func_t cmp, struct list_head *head,
struct list_head *a, struct list_head *b)
{
struct list_head *tail = head;
@@ -185,9 +182,7 @@ static void merge_final(void *priv, cmp_func cmp, struct list_head *head,
* 2^(k+1) - 1 (second merge of case 5 when x == 2^(k-1) - 1).
*/
__attribute__((nonnull(2,3)))
-void list_sort(void *priv, struct list_head *head,
- int (*cmp)(void *priv, struct list_head *a,
- struct list_head *b))
+void list_sort(void *priv, struct list_head *head, list_cmp_func_t cmp)
{
struct list_head *list = head->next, *pending = NULL;
size_t count = 0; /* Count of pending */
@@ -227,7 +222,7 @@ void list_sort(void *priv, struct list_head *head,
if (likely(bits)) {
struct list_head *a = *tail, *b = a->prev;

- a = merge(priv, (cmp_func)cmp, b, a);
+ a = merge(priv, cmp, b, a);
/* Install the merged result in place of the inputs */
a->prev = b->prev;
*tail = a;
@@ -249,10 +244,10 @@ void list_sort(void *priv, struct list_head *head,

if (!next)
break;
- list = merge(priv, (cmp_func)cmp, pending, list);
+ list = merge(priv, cmp, pending, list);
pending = next;
}
/* The final merge, rebuilding prev links */
- merge_final(priv, (cmp_func)cmp, head, pending, list);
+ merge_final(priv, cmp, head, pending, list);
}
EXPORT_SYMBOL(list_sort);
diff --git a/lib/test_list_sort.c b/lib/test_list_sort.c
index 1f017d3b610e..00daaf23316f 100644
--- a/lib/test_list_sort.c
+++ b/lib/test_list_sort.c
@@ -56,7 +56,8 @@ static int __init check(struct debug_el *ela, struct debug_el *elb)
return 0;
}

-static int __init cmp(void *priv, struct list_head *a, struct list_head *b)
+static int __init cmp(void *priv, const struct list_head *a,
+ const struct list_head *b)
{
struct debug_el *ela, *elb;

diff --git a/net/tipc/name_table.c b/net/tipc/name_table.c
index ee5ac40ea2b6..f8141443f2e2 100644
--- a/net/tipc/name_table.c
+++ b/net/tipc/name_table.c
@@ -397,8 +397,8 @@ static struct publication *tipc_service_remove_publ(struct service_range *sr,
* Code reused: time_after32() for the same purpose
*/
#define publication_after(pa, pb) time_after32((pa)->id, (pb)->id)
-static int tipc_publ_sort(void *priv, struct list_head *a,
- struct list_head *b)
+static int tipc_publ_sort(void *priv, const struct list_head *a,
+ const struct list_head *b)
{
struct publication *pa, *pb;

--
2.31.1.295.g9ea45b61b8-goog