#include <linux/fs.h>
#include <linux/fdtable.h>
#include <linux/filter.h>
+#include <linux/bpf_mem_alloc.h>
#include <linux/btf_ids.h>
+#include <linux/mm_types.h>
#include "mmap_unlock_work.h"
static const char * const iter_task_type_names[] = {
u32 *tid,
bool skip_if_dup_files)
{
- struct task_struct *task, *next_task;
+ struct task_struct *task;
struct pid *pid;
- u32 saved_tid;
+ u32 next_tid;
if (!*tid) {
/* The first time, the iterator calls this function. */
pid = find_pid_ns(common->pid, common->ns);
- if (!pid)
- return NULL;
-
task = get_pid_task(pid, PIDTYPE_TGID);
if (!task)
return NULL;
return task;
}
- pid = find_pid_ns(common->pid_visiting, common->ns);
- if (!pid)
- return NULL;
-
- task = get_pid_task(pid, PIDTYPE_PID);
+ task = find_task_by_pid_ns(common->pid_visiting, common->ns);
if (!task)
return NULL;
retry:
- if (!pid_alive(task)) {
- put_task_struct(task);
- return NULL;
- }
+ task = next_thread(task);
- next_task = next_thread(task);
- put_task_struct(task);
- if (!next_task)
- return NULL;
-
- saved_tid = *tid;
- *tid = __task_pid_nr_ns(next_task, PIDTYPE_PID, common->ns);
- if (!*tid || *tid == common->pid) {
+ next_tid = __task_pid_nr_ns(task, PIDTYPE_PID, common->ns);
+ if (!next_tid || next_tid == common->pid) {
/* Run out of tasks of a process. The tasks of a
* thread_group are linked as circular linked list.
*/
- *tid = saved_tid;
return NULL;
}
- get_task_struct(next_task);
- common->pid_visiting = *tid;
-
- if (skip_if_dup_files && task->files == task->group_leader->files) {
- task = next_task;
+ if (skip_if_dup_files && task->files == task->group_leader->files)
goto retry;
- }
- return next_task;
+ *tid = common->pid_visiting = next_tid;
+ get_task_struct(task);
+ return task;
}
static struct task_struct *task_seq_get_next(struct bpf_iter_seq_task_common *common,
.arg5_type = ARG_ANYTHING,
};
+struct bpf_iter_task_vma_kern_data {
+ struct task_struct *task;
+ struct mm_struct *mm;
+ struct mmap_unlock_irq_work *work;
+ struct vma_iterator vmi;
+};
+
+struct bpf_iter_task_vma {
+ /* opaque iterator state; having __u64 here allows to preserve correct
+ * alignment requirements in vmlinux.h, generated from BTF
+ */
+ __u64 __opaque[1];
+} __attribute__((aligned(8)));
+
+/* Non-opaque version of bpf_iter_task_vma */
+struct bpf_iter_task_vma_kern {
+ struct bpf_iter_task_vma_kern_data *data;
+} __attribute__((aligned(8)));
+
+__diag_push();
+__diag_ignore_all("-Wmissing-prototypes",
+ "Global functions as their definitions will be in vmlinux BTF");
+
+__bpf_kfunc int bpf_iter_task_vma_new(struct bpf_iter_task_vma *it,
+ struct task_struct *task, u64 addr)
+{
+ struct bpf_iter_task_vma_kern *kit = (void *)it;
+ bool irq_work_busy = false;
+ int err;
+
+ BUILD_BUG_ON(sizeof(struct bpf_iter_task_vma_kern) != sizeof(struct bpf_iter_task_vma));
+ BUILD_BUG_ON(__alignof__(struct bpf_iter_task_vma_kern) != __alignof__(struct bpf_iter_task_vma));
+
+ /* is_iter_reg_valid_uninit guarantees that kit hasn't been initialized
+ * before, so non-NULL kit->data doesn't point to previously
+ * bpf_mem_alloc'd bpf_iter_task_vma_kern_data
+ */
+ kit->data = bpf_mem_alloc(&bpf_global_ma, sizeof(struct bpf_iter_task_vma_kern_data));
+ if (!kit->data)
+ return -ENOMEM;
+
+ kit->data->task = get_task_struct(task);
+ kit->data->mm = task->mm;
+ if (!kit->data->mm) {
+ err = -ENOENT;
+ goto err_cleanup_iter;
+ }
+
+ /* kit->data->work == NULL is valid after bpf_mmap_unlock_get_irq_work */
+ irq_work_busy = bpf_mmap_unlock_get_irq_work(&kit->data->work);
+ if (irq_work_busy || !mmap_read_trylock(kit->data->mm)) {
+ err = -EBUSY;
+ goto err_cleanup_iter;
+ }
+
+ vma_iter_init(&kit->data->vmi, kit->data->mm, addr);
+ return 0;
+
+err_cleanup_iter:
+ if (kit->data->task)
+ put_task_struct(kit->data->task);
+ bpf_mem_free(&bpf_global_ma, kit->data);
+ /* NULL kit->data signals failed bpf_iter_task_vma initialization */
+ kit->data = NULL;
+ return err;
+}
+
+__bpf_kfunc struct vm_area_struct *bpf_iter_task_vma_next(struct bpf_iter_task_vma *it)
+{
+ struct bpf_iter_task_vma_kern *kit = (void *)it;
+
+ if (!kit->data) /* bpf_iter_task_vma_new failed */
+ return NULL;
+ return vma_next(&kit->data->vmi);
+}
+
+__bpf_kfunc void bpf_iter_task_vma_destroy(struct bpf_iter_task_vma *it)
+{
+ struct bpf_iter_task_vma_kern *kit = (void *)it;
+
+ if (kit->data) {
+ bpf_mmap_unlock_mm(kit->data->work, kit->data->mm);
+ put_task_struct(kit->data->task);
+ bpf_mem_free(&bpf_global_ma, kit->data);
+ }
+}
+
+__diag_pop();
+
+struct bpf_iter_css_task {
+ __u64 __opaque[1];
+} __attribute__((aligned(8)));
+
+struct bpf_iter_css_task_kern {
+ struct css_task_iter *css_it;
+} __attribute__((aligned(8)));
+
+__diag_push();
+__diag_ignore_all("-Wmissing-prototypes",
+ "Global functions as their definitions will be in vmlinux BTF");
+
+__bpf_kfunc int bpf_iter_css_task_new(struct bpf_iter_css_task *it,
+ struct cgroup_subsys_state *css, unsigned int flags)
+{
+ struct bpf_iter_css_task_kern *kit = (void *)it;
+
+ BUILD_BUG_ON(sizeof(struct bpf_iter_css_task_kern) != sizeof(struct bpf_iter_css_task));
+ BUILD_BUG_ON(__alignof__(struct bpf_iter_css_task_kern) !=
+ __alignof__(struct bpf_iter_css_task));
+ kit->css_it = NULL;
+ switch (flags) {
+ case CSS_TASK_ITER_PROCS | CSS_TASK_ITER_THREADED:
+ case CSS_TASK_ITER_PROCS:
+ case 0:
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ kit->css_it = bpf_mem_alloc(&bpf_global_ma, sizeof(struct css_task_iter));
+ if (!kit->css_it)
+ return -ENOMEM;
+ css_task_iter_start(css, flags, kit->css_it);
+ return 0;
+}
+
+__bpf_kfunc struct task_struct *bpf_iter_css_task_next(struct bpf_iter_css_task *it)
+{
+ struct bpf_iter_css_task_kern *kit = (void *)it;
+
+ if (!kit->css_it)
+ return NULL;
+ return css_task_iter_next(kit->css_it);
+}
+
+__bpf_kfunc void bpf_iter_css_task_destroy(struct bpf_iter_css_task *it)
+{
+ struct bpf_iter_css_task_kern *kit = (void *)it;
+
+ if (!kit->css_it)
+ return;
+ css_task_iter_end(kit->css_it);
+ bpf_mem_free(&bpf_global_ma, kit->css_it);
+}
+
+__diag_pop();
+
+struct bpf_iter_task {
+ __u64 __opaque[3];
+} __attribute__((aligned(8)));
+
+struct bpf_iter_task_kern {
+ struct task_struct *task;
+ struct task_struct *pos;
+ unsigned int flags;
+} __attribute__((aligned(8)));
+
+enum {
+ /* all process in the system */
+ BPF_TASK_ITER_ALL_PROCS,
+ /* all threads in the system */
+ BPF_TASK_ITER_ALL_THREADS,
+ /* all threads of a specific process */
+ BPF_TASK_ITER_PROC_THREADS
+};
+
+__diag_push();
+__diag_ignore_all("-Wmissing-prototypes",
+ "Global functions as their definitions will be in vmlinux BTF");
+
+__bpf_kfunc int bpf_iter_task_new(struct bpf_iter_task *it,
+ struct task_struct *task__nullable, unsigned int flags)
+{
+ struct bpf_iter_task_kern *kit = (void *)it;
+
+ BUILD_BUG_ON(sizeof(struct bpf_iter_task_kern) > sizeof(struct bpf_iter_task));
+ BUILD_BUG_ON(__alignof__(struct bpf_iter_task_kern) !=
+ __alignof__(struct bpf_iter_task));
+
+ kit->task = kit->pos = NULL;
+ switch (flags) {
+ case BPF_TASK_ITER_ALL_THREADS:
+ case BPF_TASK_ITER_ALL_PROCS:
+ break;
+ case BPF_TASK_ITER_PROC_THREADS:
+ if (!task__nullable)
+ return -EINVAL;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ if (flags == BPF_TASK_ITER_PROC_THREADS)
+ kit->task = task__nullable;
+ else
+ kit->task = &init_task;
+ kit->pos = kit->task;
+ kit->flags = flags;
+ return 0;
+}
+
+__bpf_kfunc struct task_struct *bpf_iter_task_next(struct bpf_iter_task *it)
+{
+ struct bpf_iter_task_kern *kit = (void *)it;
+ struct task_struct *pos;
+ unsigned int flags;
+
+ flags = kit->flags;
+ pos = kit->pos;
+
+ if (!pos)
+ return pos;
+
+ if (flags == BPF_TASK_ITER_ALL_PROCS)
+ goto get_next_task;
+
+ kit->pos = next_thread(kit->pos);
+ if (kit->pos == kit->task) {
+ if (flags == BPF_TASK_ITER_PROC_THREADS) {
+ kit->pos = NULL;
+ return pos;
+ }
+ } else
+ return pos;
+
+get_next_task:
+ kit->pos = next_task(kit->pos);
+ kit->task = kit->pos;
+ if (kit->pos == &init_task)
+ kit->pos = NULL;
+
+ return pos;
+}
+
+__bpf_kfunc void bpf_iter_task_destroy(struct bpf_iter_task *it)
+{
+}
+
+__diag_pop();
+
DEFINE_PER_CPU(struct mmap_unlock_irq_work, mmap_unlock_work);
static void do_mmap_read_unlock(struct irq_work *entry)
projects / linux-2.6-microblaze.git / blobdiff