kernel-6.5-handle-get_user_pages-vmas-argument-remova.patch

   1 From a8b9fa3504163bfe29fc9faa2aac201ace66e4da Mon Sep 17 00:00:00 2001
   2 From: Paolo Pisati <paolo.pisati@canonical.com>
   3 Date: Thu, 13 Jul 2023 13:35:33 +0000
   4 Subject: [PATCH 2/2] Linux 6.5: handle get_user_pages() vmas argument removal
   5
   6 commit b2cac248191b7466c5819e0da617b0705a26e197 "mm/gup: removed vmas
   7 array from internal GUP functions" removed vmas arg from
   8 __get_user_pages_locked()[*], and to handle that we do two things:
   9
  10 1) when caller vmas arg was NULL, blindly substitute the call with the new API.
  11
  12 2) when caller vmas was a real array (and the caller expected it to be
  13    populated upon return), reimplement the internal "for(;;) vma = vma_find(); vmas[i] = vma;"
  14    loop that was partially removed.
  15
  16 *: get_user_pages() is a wrapper around __get_user_pages_locked()
  17
  18 Signed-off-by: Paolo Pisati <paolo.pisati@canonical.com>
  19 ---
  20  common/inc/nv-mm.h | 56 +++++++++++++------
  21  conftest.sh        | 26 ++++++++-
  22  nvidia-drm/nvidia-drm-linux.c             |  5 ++
  23  nvidia-uvm/uvm8_tools.c    | 24 ++++++++
  24  nvidia/kernel/os-mlock.c  |  5 ++
  25  5 files changed, 97 insertions(+), 19 deletions(-)
  26
  27 diff --git a/kernel/common/inc/nv-mm.h b/kernel/common/inc/nv-mm.h
  28 index 51d0df4a..86bf6036 100644
  29 --- a/kernel/common/inc/nv-mm.h
  30 +++ b/kernel/common/inc/nv-mm.h
  31 @@ -77,24 +77,44 @@ typedef int vm_fault_t;
  32      #if defined(NV_GET_USER_PAGES_HAS_WRITE_AND_FORCE_ARGS)
  33          #define NV_GET_USER_PAGES get_user_pages
  34      #else
  35 -        #include <linux/mm.h>
  36 -
  37 -        static inline long NV_GET_USER_PAGES(unsigned long start,
  38 -                                             unsigned long nr_pages,
  39 -                                             int write,
  40 -                                             int force,
  41 -                                             struct page **pages,
  42 -                                             struct vm_area_struct **vmas)
  43 -        {
  44 -            unsigned int flags = 0;
  45 -
  46 -            if (write)
  47 -                flags |= FOLL_WRITE;
  48 -            if (force)
  49 -                flags |= FOLL_FORCE;
  50 -
  51 -            return get_user_pages(start, nr_pages, flags, pages, vmas);
  52 -        }
  53 +       #if defined(NV_GET_USER_PAGES_DROPPED_VMA)
  54 +            #include <linux/mm.h>
  55 +
  56 +            static inline long NV_GET_USER_PAGES(unsigned long start,
  57 +                                                 unsigned long nr_pages,
  58 +                                                 int write,
  59 +                                                 int force,
  60 +                                                 struct page **pages)
  61 +            {
  62 +                unsigned int flags = 0;
  63 +
  64 +                if (write)
  65 +                    flags |= FOLL_WRITE;
  66 +                if (force)
  67 +                    flags |= FOLL_FORCE;
  68 +
  69 +                return get_user_pages(start, nr_pages, flags, pages);
  70 +            }
  71 +       #else
  72 +            #include <linux/mm.h>
  73 +
  74 +            static inline long NV_GET_USER_PAGES(unsigned long start,
  75 +                                                 unsigned long nr_pages,
  76 +                                                 int write,
  77 +                                                 int force,
  78 +                                                 struct page **pages,
  79 +                                                 struct vm_area_struct **vmas)
  80 +            {
  81 +                unsigned int flags = 0;
  82 +
  83 +                if (write)
  84 +                    flags |= FOLL_WRITE;
  85 +                if (force)
  86 +                    flags |= FOLL_FORCE;
  87 +
  88 +                return get_user_pages(start, nr_pages, flags, pages, vmas);
  89 +            }
  90 +       #endif
  91      #endif
  92  #endif
  93
  94 diff --git a/kernel/conftest.sh b/kernel/conftest.sh
  95 index abe435ff..0131fab5 100755
  96 --- a/kernel/conftest.sh
  97 +++ b/kernel/conftest.sh
  98 @@ -3051,7 +3051,6 @@ compile_test() {
  99              # write and force parameters AND that gup has task_struct and
 100              # mm_struct as its first arguments.
 101              # Return if available.
 102 -            # Fall through to default case if absent.
 103
 104              echo "$CONFTEST_PREAMBLE
 105              #include <linux/mm.h>
 106 @@ -3075,6 +3074,31 @@ compile_test() {
 107                  return
 108              fi
 109
 110 +            # Conftest #4: check if vma arg was dropped
 111 +            # Return if available.
 112 +            # Fall through to default case if absent.
 113 +
 114 +            echo "$CONFTEST_PREAMBLE
 115 +            #include <linux/mm.h>
 116 +            long get_user_pages(unsigned long start,
 117 +                                unsigned long nr_pages,
 118 +                                unsigned int gup_flags,
 119 +                                struct page **pages) {
 120 +                return 0;
 121 +            }" > conftest$$.c
 122 +
 123 +            $CC $CFLAGS -c conftest$$.c > /dev/null 2>&1
 124 +            rm -f conftest$$.c
 125 +
 126 +            if [ -f conftest$$.o ]; then
 127 +                echo "#define NV_GET_USER_PAGES_DROPPED_VMA" | append_conftest "functions"
 128 +                echo "#undef NV_GET_USER_PAGES_HAS_WRITE_AND_FORCE_ARGS" | append_conftest "functions"
 129 +                echo "#undef NV_GET_USER_PAGES_HAS_TASK_STRUCT" | append_conftest "functions"
 130 +                 rm -f conftest$$.o
 131 +                return
 132 +            fi
 133 +
 134 +
 135              echo "#define NV_GET_USER_PAGES_HAS_WRITE_AND_FORCE_ARGS" | append_conftest "functions"
 136              echo "#define NV_GET_USER_PAGES_HAS_TASK_STRUCT" | append_conftest "functions"
 137
 138 diff --git a/kernel/nvidia-drm/nvidia-drm-linux.c b/kernel/nvidia-drm/nvidia-drm-linux.c
 139 index be405f29..dd4a2a6d 100644
 140 --- a/kernel/nvidia-drm/nvidia-drm-linux.c
 141 +++ b/kernel/nvidia-drm/nvidia-drm-linux.c
 142 @@ -115,8 +115,13 @@ int nv_drm_lock_user_pages(unsigned long address,
 143
 144      nv_mmap_read_lock(mm);
 145
 146 +#if defined(NV_GET_USER_PAGES_DROPPED_VMA)
 147 +    pages_pinned = NV_GET_USER_PAGES(address, pages_count, write, force,
 148 +                                    user_pages);
 149 +#else
 150      pages_pinned = NV_GET_USER_PAGES(address, pages_count, write, force,
 151                                       user_pages, NULL);
 152 +#endif
 153      nv_mmap_read_unlock(mm);
 154
 155      if (pages_pinned < 0 || (unsigned)pages_pinned < pages_count) {
 156 diff --git a/kernel/nvidia-uvm/uvm8_tools.c b/kernel/nvidia-uvm/uvm8_tools.c
 157 index 1dc7c97d..ea521945 100644
 158 --- a/kernel/nvidia-uvm/uvm8_tools.c
 159 +++ b/kernel/nvidia-uvm/uvm8_tools.c
 160 @@ -251,13 +251,37 @@ static NV_STATUS map_user_pages(NvU64 user_va, NvU64 size, void **addr, struct p
 161      }
 162
 163      nv_mmap_read_lock(current->mm);
 164 +#if defined(NV_GET_USER_PAGES_DROPPED_VMA)
 165 +    ret = NV_GET_USER_PAGES(user_va, num_pages, 1, 0, *pages);
 166 +#else
 167      ret = NV_GET_USER_PAGES(user_va, num_pages, 1, 0, *pages, vmas);
 168 +#endif
 169      nv_mmap_read_unlock(current->mm);
 170      if (ret != num_pages) {
 171          status = NV_ERR_INVALID_ARGUMENT;
 172          goto fail;
 173      }
 174
 175 +#if defined(NV_GET_USER_PAGES_DROPPED_VMA)
 176 +    struct vm_area_struct *vma;
 177 +    unsigned long start;
 178 +
 179 +    nv_mmap_read_lock(current->mm);
 180 +    start = user_va;
 181 +    for (i = 0; i < num_pages; i++) {
 182 +        vma = find_vma(current->mm, start);
 183 +        if (!vma) {
 184 +           nv_mmap_read_unlock(current->mm);
 185 +           status = NV_ERR_INVALID_ARGUMENT;
 186 +           goto fail;
 187 +       }
 188 +
 189 +        vmas[i] = vma;
 190 +        start = (start + PAGE_SIZE) & PAGE_MASK;
 191 +    }
 192 +    nv_mmap_read_unlock(current->mm);
 193 +#endif
 194 +
 195      for (i = 0; i < num_pages; i++) {
 196          if (page_count((*pages)[i]) > MAX_PAGE_COUNT || uvm_file_is_nvidia_uvm(vmas[i]->vm_file)) {
 197              status = NV_ERR_INVALID_ARGUMENT;
 198 diff --git a/kernel/nvidia/os-mlock.c b/kernel/nvidia/os-mlock.c
 199 index f88daed4..ad5cb9a1 100644
 200 --- a/kernel/nvidia/os-mlock.c
 201 +++ b/kernel/nvidia/kernel/os-mlock.c
 202 @@ -127,8 +127,13 @@ NV_STATUS NV_API_CALL os_lock_user_pages(
 203      }
 204
 205      nv_mmap_read_lock(mm);
 206 +#if defined(NV_GET_USER_PAGES_DROPPED_VMA)
 207 +    ret = NV_GET_USER_PAGES((unsigned long)address,
 208 +                            page_count, write, force, user_pages);
 209 +#else
 210      ret = NV_GET_USER_PAGES((unsigned long)address,
 211                              page_count, write, force, user_pages, NULL);
 212 +#endif
 213      nv_mmap_read_unlock(mm);
 214      pinned = ret;
 215
 216 --
 217 2.40.1
 218