On 3/7/19 8:50 AM, Luca Coelho wrote:
> From: Luca Coelho <luciano.coelho@xxxxxxxxx>
>
> RHEL 7.6 uses kernel v3.10 with a lot of backports from newer
> kernels. This causes compilation to break in many places when the
> backports project is used. To solve the issue, check for RHEL release
> code 7.6 where appropriate. This doesn't take into consideration
> lower versions of the kernel (i.e. < 7.6), because it's very difficult
> to find the information about when each feature was backported.
>
> Signed-off-by: Luca Coelho <luciano.coelho@xxxxxxxxx>
> ---
>
> In v2:
>
> * Fix some linking issues;
> * Fix some duplicate symbols due to backporting stuff that was
> already in RHEL's kernel;
>
> In v3:
>
> * Remove gerrit tag.
>
>
> .../backport-include/linux/bp-devcoredump.h | 3 +-
> backport/backport-include/linux/etherdevice.h | 6 +-
> backport/backport-include/linux/firmware.h | 6 +-
> .../backport-include/linux/ftrace_event.h | 3 +-
> backport/backport-include/linux/jiffies.h | 5 +
> backport/backport-include/linux/kernel.h | 3 +-
> backport/backport-include/linux/ktime.h | 3 +-
> backport/backport-include/linux/mm.h | 55 ++++++
> backport/backport-include/linux/moduleparam.h | 3 +-
> backport/backport-include/linux/netdevice.h | 12 +-
> backport/backport-include/linux/netlink.h | 3 +-
> backport/backport-include/linux/page_ref.h | 3 +-
> backport/backport-include/linux/pci.h | 3 +-
> backport/backport-include/linux/percpu.h | 3 +-
> backport/backport-include/linux/pm_runtime.h | 3 +-
> backport/backport-include/linux/property.h | 3 +-
> backport/backport-include/linux/rtnetlink.h | 3 +-
> backport/backport-include/linux/skbuff.h | 6 +-
> backport/backport-include/linux/string.h | 3 +-
> backport/backport-include/linux/time.h | 6 +
> backport/backport-include/linux/time64.h | 3 +-
> backport/backport-include/linux/timekeeping.h | 15 +-
> .../backport-include/linux/u64_stats_sync.h | 3 +-
> backport/backport-include/linux/uuid.h | 3 +-
> backport/backport-include/linux/wait.h | 6 +-
> backport/backport-include/net/genetlink.h | 6 +-
> backport/backport-include/net/inet_frag.h | 6 +-
> backport/backport-include/net/iw_handler.h | 3 +-
> backport/backport-include/net/net_namespace.h | 3 +-
> backport/backport-include/net/netlink.h | 6 +-
> backport/compat/backport-3.11.c | 2 +
> backport/compat/backport-3.13.c | 3 +-
> backport/compat/backport-3.17.c | 7 +-
> backport/compat/backport-3.19.c | 5 +-
> backport/compat/backport-4.0.c | 184 +++++++++++++++++-
> backport/compat/backport-4.1.c | 2 +
> backport/compat/backport-4.2.c | 4 +-
> backport/compat/backport-4.4.c | 3 +-
> backport/compat/backport-4.6.c | 4 +-
> backport/compat/backport-4.7.c | 3 +-
> backport/compat/backport-genetlink.c | 6 +-
> patches/0028-select_queue/mac80211.patch | 10 +-
> patches/0073-netdevice-mtu-range.cocci | 4 +-
> patches/0075-ndo-stats-64.cocci | 4 +-
> 44 files changed, 371 insertions(+), 59 deletions(-)
>
.......
> diff --git a/backport/backport-include/linux/jiffies.h b/backport/backport-include/linux/jiffies.h
> index bbadcc8cd27e..caef7db30004 100644
> --- a/backport/backport-include/linux/jiffies.h
> +++ b/backport/backport-include/linux/jiffies.h
> @@ -1,5 +1,10 @@
> #ifndef __BACKPORT_LNIUX_JIFFIES_H
> #define __BACKPORT_LNIUX_JIFFIES_H
> +
> +#ifndef NSEC_PER_SEC
> +#define NSEC_PER_SEC 1000000000L
> +#endif
This is strange, why is this only needed on RHEL?
.....
> diff --git a/backport/backport-include/linux/mm.h b/backport/backport-include/linux/mm.h
> index b28156d33625..0806f4df8f5d 100644
> --- a/backport/backport-include/linux/mm.h
> +++ b/backport/backport-include/linux/mm.h
> @@ -12,6 +12,61 @@
> void kvfree(const void *addr);
> #endif /* < 3.15 */
>
> +#if LINUX_VERSION_IS_LESS(3,20,0) && \
> + RHEL_RELEASE_CODE < RHEL_RELEASE_VERSION(7,6)
> +#define get_user_pages_locked LINUX_BACKPORT(get_user_pages_locked)
> +long get_user_pages_locked(unsigned long start, unsigned long nr_pages,
> + int write, int force, struct page **pages, int *locked);
> +#define get_user_pages_unlocked LINUX_BACKPORT(get_user_pages_unlocked)
> +long get_user_pages_unlocked(unsigned long start, unsigned long nr_pages,
> + int write, int force, struct page **pages);
> +#elif LINUX_VERSION_IS_LESS(4,6,0) && \
> + RHEL_RELEASE_CODE < RHEL_RELEASE_VERSION(7,6)
> +static inline
> +long backport_get_user_pages_locked(unsigned long start, unsigned long nr_pages,
> + int write, int force, struct page **pages, int *locked)
> +{
> + return get_user_pages_locked(current, current->mm, start, nr_pages,
> + write, force, pages, locked);
> +}
> +#define get_user_pages_locked LINUX_BACKPORT(get_user_pages_locked)
> +
> +static inline
> +long backport_get_user_pages_unlocked(unsigned long start, unsigned long nr_pages,
> + int write, int force, struct page **pages)
> +{
> + return get_user_pages_unlocked(current, current->mm, start, nr_pages,
> + write, force, pages);
> +}
> +#define get_user_pages_unlocked LINUX_BACKPORT(get_user_pages_unlocked)
> +#endif
> +
> +#if LINUX_VERSION_IS_LESS(4,6,0)
> +static inline
> +long backport_get_user_pages(unsigned long start, unsigned long nr_pages,
> + int write, int force, struct page **pages,
> + struct vm_area_struct **vmas)
> +{
> + return get_user_pages(current, current->mm, start, nr_pages,
> + write, force, pages, vmas);
> +}
> +#define get_user_pages LINUX_BACKPORT(get_user_pages)
> +#endif
> +
> +#ifndef FOLL_TRIED
> +#define FOLL_TRIED 0x800 /* a retry, previous pass started an IO */
> +#endif
> +
> +#if LINUX_VERSION_IS_LESS(4,1,9) && \
> + LINUX_VERSION_IS_GEQ(3,6,0) && \
> + RHEL_RELEASE_CODE < RHEL_RELEASE_VERSION(7,6)
> +#define page_is_pfmemalloc LINUX_BACKPORT(page_is_pfmemalloc)
> +static inline bool page_is_pfmemalloc(struct page *page)
> +{
> + return page->pfmemalloc;
> +}
> +#endif /* < 4.2 */
> +
I think these functions are not used anywhere, they wrere added for the
media backports. I had some compile problems here and just removed them.
> diff --git a/backport/compat/backport-4.0.c b/backport/compat/backport-4.0.c
> index 84a4c6bf27b7..0439bfa32abd 100644
> --- a/backport/compat/backport-4.0.c
> +++ b/backport/compat/backport-4.0.c
> @@ -17,6 +17,185 @@
> #include <linux/trace_seq.h>
> #include <asm/unaligned.h>
>
> +#if RHEL_RELEASE_CODE < RHEL_RELEASE_VERSION(7,6)
> + static __always_inline long __get_user_pages_locked(struct task_struct *tsk,
> + struct mm_struct *mm,
> + unsigned long start,
> + unsigned long nr_pages,
> + int write, int force,
> + struct page **pages,
> + struct vm_area_struct **vmas,
> + int *locked, bool notify_drop,
> + unsigned int flags)
> +{
> + long ret, pages_done;
> + bool lock_dropped;
> +
> + if (locked) {
> + /* if VM_FAULT_RETRY can be returned, vmas become invalid */
> + BUG_ON(vmas);
> + /* check caller initialized locked */
> + BUG_ON(*locked != 1);
> + }
> +
> + if (pages)
> + flags |= FOLL_GET;
> + if (write)
> + flags |= FOLL_WRITE;
> + if (force)
> + flags |= FOLL_FORCE;
> +
> + pages_done = 0;
> + lock_dropped = false;
> + for (;;) {
> + ret = __get_user_pages(tsk, mm, start, nr_pages, flags, pages,
> + vmas, locked);
> + if (!locked)
> + /* VM_FAULT_RETRY couldn't trigger, bypass */
> + return ret;
> +
> + /* VM_FAULT_RETRY cannot return errors */
> + if (!*locked) {
> + BUG_ON(ret < 0);
> + BUG_ON(ret >= nr_pages);
> + }
> +
> + if (!pages)
> + /* If it's a prefault don't insist harder */
> + return ret;
> +
> + if (ret > 0) {
> + nr_pages -= ret;
> + pages_done += ret;
> + if (!nr_pages)
> + break;
> + }
> + if (*locked) {
> + /* VM_FAULT_RETRY didn't trigger */
> + if (!pages_done)
> + pages_done = ret;
> + break;
> + }
> + /* VM_FAULT_RETRY triggered, so seek to the faulting offset */
> + pages += ret;
> + start += ret << PAGE_SHIFT;
> +
> + /*
> + * Repeat on the address that fired VM_FAULT_RETRY
> + * without FAULT_FLAG_ALLOW_RETRY but with
> + * FAULT_FLAG_TRIED.
> + */
> + *locked = 1;
> + lock_dropped = true;
> + down_read(&mm->mmap_sem);
> + ret = __get_user_pages(tsk, mm, start, 1, flags | FOLL_TRIED,
> + pages, NULL, NULL);
> + if (ret != 1) {
> + BUG_ON(ret > 1);
> + if (!pages_done)
> + pages_done = ret;
> + break;
> + }
> + nr_pages--;
> + pages_done++;
> + if (!nr_pages)
> + break;
> + pages++;
> + start += PAGE_SIZE;
> + }
> + if (notify_drop && lock_dropped && *locked) {
> + /*
> + * We must let the caller know we temporarily dropped the lock
> + * and so the critical section protected by it was lost.
> + */
> + up_read(&mm->mmap_sem);
> + *locked = 0;
> + }
> + return pages_done;
> +}
> +
> +/*
> + * We can leverage the VM_FAULT_RETRY functionality in the page fault
> + * paths better by using either get_user_pages_locked() or
> + * get_user_pages_unlocked().
> + *
> + * get_user_pages_locked() is suitable to replace the form:
> + *
> + * down_read(&mm->mmap_sem);
> + * do_something()
> + * get_user_pages(tsk, mm, ..., pages, NULL);
> + * up_read(&mm->mmap_sem);
> + *
> + * to:
> + *
> + * int locked = 1;
> + * down_read(&mm->mmap_sem);
> + * do_something()
> + * get_user_pages_locked(tsk, mm, ..., pages, &locked);
> + * if (locked)
> + * up_read(&mm->mmap_sem);
> + */
> +long get_user_pages_locked(unsigned long start, unsigned long nr_pages,
> + int write, int force, struct page **pages,
> + int *locked)
> +{
> + return __get_user_pages_locked(current, current->mm, start, nr_pages,
> + write, force, pages, NULL, locked, true,
> + FOLL_TOUCH);
> +}
> +EXPORT_SYMBOL_GPL(get_user_pages_locked);
> +
> +/*
> + * Same as get_user_pages_unlocked(...., FOLL_TOUCH) but it allows to
> + * pass additional gup_flags as last parameter (like FOLL_HWPOISON).
> + *
> + * NOTE: here FOLL_TOUCH is not set implicitly and must be set by the
> + * caller if required (just like with __get_user_pages). "FOLL_GET",
> + * "FOLL_WRITE" and "FOLL_FORCE" are set implicitly as needed
> + * according to the parameters "pages", "write", "force"
> + * respectively.
> + */
> +static __always_inline long __get_user_pages_unlocked(struct task_struct *tsk, struct mm_struct *mm,
> + unsigned long start, unsigned long nr_pages,
> + int write, int force, struct page **pages,
> + unsigned int gup_flags)
> +{
> + long ret;
> + int locked = 1;
> + down_read(&mm->mmap_sem);
> + ret = __get_user_pages_locked(tsk, mm, start, nr_pages, write, force,
> + pages, NULL, &locked, false, gup_flags);
> + if (locked)
> + up_read(&mm->mmap_sem);
> + return ret;
> +}
> +
> +/*
> + * get_user_pages_unlocked() is suitable to replace the form:
> + *
> + * down_read(&mm->mmap_sem);
> + * get_user_pages(tsk, mm, ..., pages, NULL);
> + * up_read(&mm->mmap_sem);
> + *
> + * with:
> + *
> + * get_user_pages_unlocked(tsk, mm, ..., pages);
> + *
> + * It is functionally equivalent to get_user_pages_fast so
> + * get_user_pages_fast should be used instead, if the two parameters
> + * "tsk" and "mm" are respectively equal to current and current->mm,
> + * or if "force" shall be set to 1 (get_user_pages_fast misses the
> + * "force" parameter).
> + */
> +long get_user_pages_unlocked(unsigned long start, unsigned long nr_pages,
> + int write, int force, struct page **pages)
> +{
> + return __get_user_pages_unlocked(current, current->mm, start, nr_pages,
> + write, force, pages, FOLL_TOUCH);
> +}
> +EXPORT_SYMBOL_GPL(get_user_pages_unlocked);
> +#endif
> +
> /**
> * hex_dump_to_buffer - convert a blob of data to "hex ASCII" in memory
> * @buf: data blob to dump
I think this also not needed.
Hauke
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