zlogger: drop old kernel support

The oldest kernel this is currently built against is 5.15.

Change-Id: I4b02abcd5785fe75c79eb05f30aa68ce1d555b71
Signed-off-by: Mateusz Majewski <m.majewski2@samsung.com>

diff --git a/kernel/zlogger/zlogger.c b/kernel/zlogger/zlogger.c
index 1c047a9..c99630a 100644 (file)
--- a/kernel/zlogger/zlogger.c
+++ b/kernel/zlogger/zlogger.c
@@ -130,13 +130,6 @@ module_param_named(zlog_enable, g_zlog_enable, int, 0644);
 
 static int zlogger_unmap(struct thread_table_field *ptr);
 
-#if (KERNEL_VERSION(3, 17, 0) > LINUX_VERSION_CODE)
-static inline u64 ktime_get_ns(void)
-{
-       return ktime_to_ns(ktime_get());
-}
-#endif
-
 static struct thread_table_field *get_thread_table(pid_t tid, bool is_stdout)
 {
        struct thread_table_field *ptr = NULL;
@@ -406,14 +399,9 @@ static void zlogger_vm_close(struct vm_area_struct *vma)
 }
 
 /* called under mmap semaphore */
-#if LINUX_VERSION_CODE >= KERNEL_VERSION(4, 11, 0)
 static vm_fault_t zlogger_fault(struct vm_fault *vmf)
 {
        struct vm_area_struct *vma = vmf->vma;
-#else
-static int zlogger_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
-{
-#endif
        struct thread_table_field *ptr;
        void *p = NULL;
        struct page *page;
@@ -431,11 +419,7 @@ static int zlogger_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
 
        page = virt_to_page((unsigned long)p);
 
-#if LINUX_VERSION_CODE >= KERNEL_VERSION(4, 11, 0)
        return vmf_insert_pfn(vma, vma->vm_start, page_to_pfn(page));
-#else
-       return vm_insert_pfn(vma, vma->vm_start, page_to_pfn(page));
-#endif
 }
 
 static const struct vm_operations_struct zlogger_vm_ops = {
@@ -485,24 +469,13 @@ static int zlogger_unmap(struct thread_table_field *ptr)
        if (!ptr->vma)
                return 0;
 
-#if LINUX_VERSION_CODE >= KERNEL_VERSION(5, 8, 0)
        if (mmap_write_lock_killable(vma->vm_mm))
                return -EINTR;
-#elif LINUX_VERSION_CODE >= KERNEL_VERSION(4, 7, 0)
-       if (down_write_killable(&vma->vm_mm->mmap_sem))
-               return -EINTR;
-#else
-       down_write(&vma->vm_mm->mmap_sem);
-#endif
 
        zap_vma_ptes(vma, vma->vm_start, vma->vm_end - vma->vm_start);
        vma->vm_private_data = NULL;
 
-#if LINUX_VERSION_CODE >= KERNEL_VERSION(5, 8, 0)
        mmap_write_unlock(vma->vm_mm);
-#else
-       up_write(&vma->vm_mm->mmap_sem);
-#endif
        return 0;
 }
 
@@ -535,24 +508,13 @@ static int zlogger_realloc_mmap(struct file *filp)
 
        page = virt_to_page((unsigned long)p);
 
-#if LINUX_VERSION_CODE >= KERNEL_VERSION(5, 8, 0)
        if (mmap_write_lock_killable(current->mm))
                return -EINTR;
-#elif LINUX_VERSION_CODE >= KERNEL_VERSION(4, 7, 0)
-       if (down_write_killable(&current->mm->mmap_sem))
-               return -EINTR;
-#else
-       down_write(&current->mm->mmap_sem);
-#endif
 
        zap_vma_ptes(vma, vma->vm_start, vma->vm_end - vma->vm_start);
        ret = remap_pfn_range(vma, vma->vm_start, page_to_pfn(page), ZLOGGER_BLOCK_SIZE, vma->vm_page_prot);
 
-#if LINUX_VERSION_CODE >= KERNEL_VERSION(5, 8, 0)
        mmap_write_unlock(current->mm);
-#else
-       up_write(&current->mm->mmap_sem);
-#endif
 
        return ret;
 }