drivers/xen/xen-front-pgdir-shbuf.c:84: warning: Function parameter or member 'buf' not described in 'xen_front_pgdir_shbuf_get_dir_start'
From: kernel test robot
Date: Thu Nov 02 2023 - 20:46:36 EST
tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
head: 4652b8e4f3ffa48c706ec334f048c217a7d9750d
commit: 58f9d806d16a38ed3bae11e2ada83393436a4956 ALSA: xen-front: Use Xen common shared buffer implementation
date: 4 years, 11 months ago
config: x86_64-buildonly-randconfig-002-20231101 (https://download.01.org/0day-ci/archive/20231103/202311030829.XIMWb8FF-lkp@xxxxxxxxx/config)
compiler: gcc-12 (Debian 12.2.0-14) 12.2.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20231103/202311030829.XIMWb8FF-lkp@xxxxxxxxx/reproduce)
If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@xxxxxxxxx>
| Closes: https://lore.kernel.org/oe-kbuild-all/202311030829.XIMWb8FF-lkp@xxxxxxxxx/
All warnings (new ones prefixed by >>):
drivers/xen/xen-front-pgdir-shbuf.c:39: warning: cannot understand function prototype: 'struct xen_page_directory '
drivers/xen/xen-front-pgdir-shbuf.c:50: warning: cannot understand function prototype: 'struct xen_front_pgdir_shbuf_ops '
>> drivers/xen/xen-front-pgdir-shbuf.c:84: warning: Function parameter or member 'buf' not described in 'xen_front_pgdir_shbuf_get_dir_start'
>> drivers/xen/xen-front-pgdir-shbuf.c:104: warning: Function parameter or member 'buf' not described in 'xen_front_pgdir_shbuf_map'
>> drivers/xen/xen-front-pgdir-shbuf.c:125: warning: Function parameter or member 'buf' not described in 'xen_front_pgdir_shbuf_unmap'
>> drivers/xen/xen-front-pgdir-shbuf.c:140: warning: Function parameter or member 'buf' not described in 'xen_front_pgdir_shbuf_free'
drivers/xen/xen-front-pgdir-shbuf.c:168: warning: Function parameter or member 'buf' not described in 'get_num_pages_dir'
drivers/xen/xen-front-pgdir-shbuf.c:179: warning: Function parameter or member 'buf' not described in 'backend_calc_num_grefs'
drivers/xen/xen-front-pgdir-shbuf.c:191: warning: Function parameter or member 'buf' not described in 'guest_calc_num_grefs'
drivers/xen/xen-front-pgdir-shbuf.c:210: warning: Function parameter or member 'buf' not described in 'backend_unmap'
>> drivers/xen/xen-front-pgdir-shbuf.c:257: warning: Function parameter or member 'buf' not described in 'backend_map'
drivers/xen/xen-front-pgdir-shbuf.c:335: warning: Function parameter or member 'buf' not described in 'backend_fill_page_dir'
drivers/xen/xen-front-pgdir-shbuf.c:362: warning: Function parameter or member 'buf' not described in 'guest_fill_page_dir'
>> drivers/xen/xen-front-pgdir-shbuf.c:406: warning: Function parameter or member 'buf' not described in 'guest_grant_refs_for_buffer'
>> drivers/xen/xen-front-pgdir-shbuf.c:406: warning: Function parameter or member 'priv_gref_head' not described in 'guest_grant_refs_for_buffer'
drivers/xen/xen-front-pgdir-shbuf.c:406: warning: Function parameter or member 'gref_idx' not described in 'guest_grant_refs_for_buffer'
drivers/xen/xen-front-pgdir-shbuf.c:433: warning: Function parameter or member 'buf' not described in 'grant_references'
>> drivers/xen/xen-front-pgdir-shbuf.c:478: warning: Function parameter or member 'buf' not described in 'alloc_storage'
>> drivers/xen/xen-front-pgdir-shbuf.c:518: warning: Function parameter or member 'cfg' not described in 'xen_front_pgdir_shbuf_alloc'
vim +84 drivers/xen/xen-front-pgdir-shbuf.c
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 71
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 72 /**
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 73 * Get granted reference to the very first page of the
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 74 * page directory. Usually this is passed to the backend,
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 75 * so it can find/fill the grant references to the buffer's
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 76 * pages.
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 77 *
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 78 * \param buf shared buffer which page directory is of interest.
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 79 * \return granted reference to the very first page of the
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 80 * page directory.
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 81 */
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 82 grant_ref_t
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 83 xen_front_pgdir_shbuf_get_dir_start(struct xen_front_pgdir_shbuf *buf)
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 @84 {
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 85 if (!buf->grefs)
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 86 return GRANT_INVALID_REF;
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 87
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 88 return buf->grefs[0];
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 89 }
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 90 EXPORT_SYMBOL_GPL(xen_front_pgdir_shbuf_get_dir_start);
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 91
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 92 /**
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 93 * Map granted references of the shared buffer.
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 94 *
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 95 * Depending on the shared buffer mode of allocation
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 96 * (be_alloc flag) this can either do nothing (for buffers
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 97 * shared by the frontend itself) or map the provided granted
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 98 * references onto the backing storage (buf->pages).
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 99 *
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 100 * \param buf shared buffer which grants to be maped.
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 101 * \return zero on success or a negative number on failure.
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 102 */
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 103 int xen_front_pgdir_shbuf_map(struct xen_front_pgdir_shbuf *buf)
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 @104 {
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 105 if (buf->ops && buf->ops->map)
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 106 return buf->ops->map(buf);
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 107
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 108 /* No need to map own grant references. */
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 109 return 0;
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 110 }
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 111 EXPORT_SYMBOL_GPL(xen_front_pgdir_shbuf_map);
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 112
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 113 /**
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 114 * Unmap granted references of the shared buffer.
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 115 *
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 116 * Depending on the shared buffer mode of allocation
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 117 * (be_alloc flag) this can either do nothing (for buffers
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 118 * shared by the frontend itself) or unmap the provided granted
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 119 * references.
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 120 *
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 121 * \param buf shared buffer which grants to be unmaped.
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 122 * \return zero on success or a negative number on failure.
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 123 */
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 124 int xen_front_pgdir_shbuf_unmap(struct xen_front_pgdir_shbuf *buf)
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 @125 {
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 126 if (buf->ops && buf->ops->unmap)
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 127 return buf->ops->unmap(buf);
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 128
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 129 /* No need to unmap own grant references. */
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 130 return 0;
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 131 }
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 132 EXPORT_SYMBOL_GPL(xen_front_pgdir_shbuf_unmap);
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 133
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 134 /**
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 135 * Free all the resources of the shared buffer.
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 136 *
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 137 * \param buf shared buffer which resources to be freed.
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 138 */
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 139 void xen_front_pgdir_shbuf_free(struct xen_front_pgdir_shbuf *buf)
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 @140 {
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 141 if (buf->grefs) {
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 142 int i;
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 143
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 144 for (i = 0; i < buf->num_grefs; i++)
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 145 if (buf->grefs[i] != GRANT_INVALID_REF)
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 146 gnttab_end_foreign_access(buf->grefs[i],
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 147 0, 0UL);
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 148 }
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 149 kfree(buf->grefs);
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 150 kfree(buf->directory);
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 151 }
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 152 EXPORT_SYMBOL_GPL(xen_front_pgdir_shbuf_free);
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 153
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 154 /*
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 155 * Number of grefs a page can hold with respect to the
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 156 * struct xen_page_directory header.
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 157 */
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 158 #define XEN_NUM_GREFS_PER_PAGE ((PAGE_SIZE - \
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 159 offsetof(struct xen_page_directory, \
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 160 gref)) / sizeof(grant_ref_t))
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 161
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 162 /**
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 163 * Get the number of pages the page directory consumes itself.
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 164 *
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 165 * \param buf shared buffer.
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 166 */
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 167 static int get_num_pages_dir(struct xen_front_pgdir_shbuf *buf)
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 168 {
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 169 return DIV_ROUND_UP(buf->num_pages, XEN_NUM_GREFS_PER_PAGE);
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 170 }
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 171
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 172 /**
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 173 * Calculate the number of grant references needed to share the buffer
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 174 * and its pages when backend allocates the buffer.
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 175 *
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 176 * \param buf shared buffer.
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 177 */
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 178 static void backend_calc_num_grefs(struct xen_front_pgdir_shbuf *buf)
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 179 {
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 180 /* Only for pages the page directory consumes itself. */
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 181 buf->num_grefs = get_num_pages_dir(buf);
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 182 }
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 183
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 184 /**
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 185 * Calculate the number of grant references needed to share the buffer
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 186 * and its pages when frontend allocates the buffer.
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 187 *
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 188 * \param buf shared buffer.
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 189 */
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 190 static void guest_calc_num_grefs(struct xen_front_pgdir_shbuf *buf)
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 191 {
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 192 /*
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 193 * Number of pages the page directory consumes itself
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 194 * plus grefs for the buffer pages.
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 195 */
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 196 buf->num_grefs = get_num_pages_dir(buf) + buf->num_pages;
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 197 }
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 198
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 199 #define xen_page_to_vaddr(page) \
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 200 ((uintptr_t)pfn_to_kaddr(page_to_xen_pfn(page)))
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 201
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 202 /**
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 203 * Unmap the buffer previously mapped with grant references
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 204 * provided by the backend.
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 205 *
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 206 * \param buf shared buffer.
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 207 * \return zero on success or a negative number on failure.
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 208 */
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 209 static int backend_unmap(struct xen_front_pgdir_shbuf *buf)
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 210 {
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 211 struct gnttab_unmap_grant_ref *unmap_ops;
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 212 int i, ret;
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 213
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 214 if (!buf->pages || !buf->backend_map_handles || !buf->grefs)
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 215 return 0;
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 216
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 217 unmap_ops = kcalloc(buf->num_pages, sizeof(*unmap_ops),
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 218 GFP_KERNEL);
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 219 if (!unmap_ops)
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 220 return -ENOMEM;
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 221
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 222 for (i = 0; i < buf->num_pages; i++) {
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 223 phys_addr_t addr;
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 224
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 225 addr = xen_page_to_vaddr(buf->pages[i]);
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 226 gnttab_set_unmap_op(&unmap_ops[i], addr, GNTMAP_host_map,
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 227 buf->backend_map_handles[i]);
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 228 }
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 229
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 230 ret = gnttab_unmap_refs(unmap_ops, NULL, buf->pages,
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 231 buf->num_pages);
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 232
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 233 for (i = 0; i < buf->num_pages; i++) {
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 234 if (unlikely(unmap_ops[i].status != GNTST_okay))
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 235 dev_err(&buf->xb_dev->dev,
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 236 "Failed to unmap page %d: %d\n",
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 237 i, unmap_ops[i].status);
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 238 }
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 239
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 240 if (ret)
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 241 dev_err(&buf->xb_dev->dev,
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 242 "Failed to unmap grant references, ret %d", ret);
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 243
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 244 kfree(unmap_ops);
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 245 kfree(buf->backend_map_handles);
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 246 buf->backend_map_handles = NULL;
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 247 return ret;
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 248 }
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 249
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 250 /**
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 251 * Map the buffer with grant references provided by the backend.
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 252 *
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 253 * \param buf shared buffer.
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 254 * \return zero on success or a negative number on failure.
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 255 */
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 256 static int backend_map(struct xen_front_pgdir_shbuf *buf)
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 @257 {
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 258 struct gnttab_map_grant_ref *map_ops = NULL;
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 259 unsigned char *ptr;
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 260 int ret, cur_gref, cur_dir_page, cur_page, grefs_left;
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 261
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 262 map_ops = kcalloc(buf->num_pages, sizeof(*map_ops), GFP_KERNEL);
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 263 if (!map_ops)
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 264 return -ENOMEM;
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 265
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 266 buf->backend_map_handles = kcalloc(buf->num_pages,
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 267 sizeof(*buf->backend_map_handles),
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 268 GFP_KERNEL);
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 269 if (!buf->backend_map_handles) {
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 270 kfree(map_ops);
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 271 return -ENOMEM;
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 272 }
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 273
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 274 /*
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 275 * Read page directory to get grefs from the backend: for external
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 276 * buffer we only allocate buf->grefs for the page directory,
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 277 * so buf->num_grefs has number of pages in the page directory itself.
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 278 */
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 279 ptr = buf->directory;
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 280 grefs_left = buf->num_pages;
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 281 cur_page = 0;
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 282 for (cur_dir_page = 0; cur_dir_page < buf->num_grefs; cur_dir_page++) {
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 283 struct xen_page_directory *page_dir =
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 284 (struct xen_page_directory *)ptr;
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 285 int to_copy = XEN_NUM_GREFS_PER_PAGE;
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 286
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 287 if (to_copy > grefs_left)
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 288 to_copy = grefs_left;
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 289
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 290 for (cur_gref = 0; cur_gref < to_copy; cur_gref++) {
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 291 phys_addr_t addr;
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 292
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 293 addr = xen_page_to_vaddr(buf->pages[cur_page]);
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 294 gnttab_set_map_op(&map_ops[cur_page], addr,
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 295 GNTMAP_host_map,
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 296 page_dir->gref[cur_gref],
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 297 buf->xb_dev->otherend_id);
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 298 cur_page++;
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 299 }
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 300
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 301 grefs_left -= to_copy;
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 302 ptr += PAGE_SIZE;
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 303 }
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 304 ret = gnttab_map_refs(map_ops, NULL, buf->pages, buf->num_pages);
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 305
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 306 /* Save handles even if error, so we can unmap. */
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 307 for (cur_page = 0; cur_page < buf->num_pages; cur_page++) {
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 308 buf->backend_map_handles[cur_page] = map_ops[cur_page].handle;
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 309 if (unlikely(map_ops[cur_page].status != GNTST_okay))
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 310 dev_err(&buf->xb_dev->dev,
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 311 "Failed to map page %d: %d\n",
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 312 cur_page, map_ops[cur_page].status);
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 313 }
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 314
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 315 if (ret) {
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 316 dev_err(&buf->xb_dev->dev,
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 317 "Failed to map grant references, ret %d", ret);
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 318 backend_unmap(buf);
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 319 }
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 320
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 321 kfree(map_ops);
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 322 return ret;
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 323 }
b3383974fee272 Oleksandr Andrushchenko 2018-11-30 324
:::::: The code at line 84 was first introduced by commit
:::::: b3383974fee272ad0d444a2d083f456879447cd8 xen: Introduce shared buffer helpers for page directory...
:::::: TO: Oleksandr Andrushchenko <oleksandr_andrushchenko@xxxxxxxx>
:::::: CC: Boris Ostrovsky <boris.ostrovsky@xxxxxxxxxx>
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki