From: Alexei Starovoitov <ast@xxxxxxxxxx>
Subsequent patches introduce bpf_arena that imposes special alignment
requirements on address selection.
Acked-by: Kumar Kartikeya Dwivedi <memxor@xxxxxxxxx>
Signed-off-by: Alexei Starovoitov <ast@xxxxxxxxxx>
---
include/linux/bpf.h | 3 +++
kernel/bpf/syscall.c | 16 ++++++++++++++++
2 files changed, 19 insertions(+)
diff --git a/include/linux/bpf.h b/include/linux/bpf.h
index 785660810e6a..95e07673cdc1 100644
--- a/include/linux/bpf.h
+++ b/include/linux/bpf.h
@@ -139,6 +139,9 @@ struct bpf_map_ops {
int (*map_mmap)(struct bpf_map *map, struct vm_area_struct *vma);
__poll_t (*map_poll)(struct bpf_map *map, struct file *filp,
struct poll_table_struct *pts);
+ unsigned long (*map_get_unmapped_area)(struct file *filep, unsigned long addr,
+ unsigned long len, unsigned long pgoff,
+ unsigned long flags);
/* Functions called by bpf_local_storage maps */
int (*map_local_storage_charge)(struct bpf_local_storage_map *smap,
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index b2750b79ac80..f63f4da4db5e 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -937,6 +937,21 @@ static __poll_t bpf_map_poll(struct file *filp, struct poll_table_struct *pts)
return EPOLLERR;
}
+static unsigned long bpf_get_unmapped_area(struct file *filp, unsigned long addr,
+ unsigned long len, unsigned long pgoff,
+ unsigned long flags)
+{
+ struct bpf_map *map = filp->private_data;
+
+ if (map->ops->map_get_unmapped_area)
+ return map->ops->map_get_unmapped_area(filp, addr, len, pgoff, flags);
+#ifdef CONFIG_MMU
+ return current->mm->get_unmapped_area(filp, addr, len, pgoff, flags);
+#else
+ return addr;
+#endif
+}
+
const struct file_operations bpf_map_fops = {
#ifdef CONFIG_PROC_FS
.show_fdinfo = bpf_map_show_fdinfo,
@@ -946,6 +961,7 @@ const struct file_operations bpf_map_fops = {
.write = bpf_dummy_write,
.mmap = bpf_map_mmap,
.poll = bpf_map_poll,
+ .get_unmapped_area = bpf_get_unmapped_area,
};
int bpf_map_new_fd(struct bpf_map *map, int flags)
--
2.43.0
