return item == swp_to_radix_entry(swap);
}
+/*
+ * Definitions for "huge tmpfs": tmpfs mounted with the huge= option
+ *
+ * SHMEM_HUGE_NEVER:
+ * disables huge pages for the mount;
+ * SHMEM_HUGE_ALWAYS:
+ * enables huge pages for the mount;
+ * SHMEM_HUGE_WITHIN_SIZE:
+ * only allocate huge pages if the page will be fully within i_size,
+ * also respect fadvise()/madvise() hints;
+ * SHMEM_HUGE_ADVISE:
+ * only allocate huge pages if requested with fadvise()/madvise();
+ */
+
+#define SHMEM_HUGE_NEVER 0
+#define SHMEM_HUGE_ALWAYS 1
+#define SHMEM_HUGE_WITHIN_SIZE 2
+#define SHMEM_HUGE_ADVISE 3
+
+/*
+ * Special values.
+ * Only can be set via /sys/kernel/mm/transparent_hugepage/shmem_enabled:
+ *
+ * SHMEM_HUGE_DENY:
+ * disables huge on shm_mnt and all mounts, for emergency use;
+ * SHMEM_HUGE_FORCE:
+ * enables huge on shm_mnt and all mounts, w/o needing option, for testing;
+ *
+ */
+#define SHMEM_HUGE_DENY (-1)
+#define SHMEM_HUGE_FORCE (-2)
+
+#ifdef CONFIG_TRANSPARENT_HUGEPAGE
+/* ifdef here to avoid bloating shmem.o when not necessary */
+
+int shmem_huge __read_mostly;
+
+static int shmem_parse_huge(const char *str)
+{
+ if (!strcmp(str, "never"))
+ return SHMEM_HUGE_NEVER;
+ if (!strcmp(str, "always"))
+ return SHMEM_HUGE_ALWAYS;
+ if (!strcmp(str, "within_size"))
+ return SHMEM_HUGE_WITHIN_SIZE;
+ if (!strcmp(str, "advise"))
+ return SHMEM_HUGE_ADVISE;
+ if (!strcmp(str, "deny"))
+ return SHMEM_HUGE_DENY;
+ if (!strcmp(str, "force"))
+ return SHMEM_HUGE_FORCE;
+ return -EINVAL;
+}
+
+static const char *shmem_format_huge(int huge)
+{
+ switch (huge) {
+ case SHMEM_HUGE_NEVER:
+ return "never";
+ case SHMEM_HUGE_ALWAYS:
+ return "always";
+ case SHMEM_HUGE_WITHIN_SIZE:
+ return "within_size";
+ case SHMEM_HUGE_ADVISE:
+ return "advise";
+ case SHMEM_HUGE_DENY:
+ return "deny";
+ case SHMEM_HUGE_FORCE:
+ return "force";
+ default:
+ VM_BUG_ON(1);
+ return "bad_val";
+ }
+}
+
+#else /* !CONFIG_TRANSPARENT_HUGEPAGE */
+
+#define shmem_huge SHMEM_HUGE_DENY
+
+#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
+
/*
* Like add_to_page_cache_locked, but error if expected item has gone.
*/
sbinfo->gid = make_kgid(current_user_ns(), gid);
if (!gid_valid(sbinfo->gid))
goto bad_val;
+#ifdef CONFIG_TRANSPARENT_HUGEPAGE
+ } else if (!strcmp(this_char, "huge")) {
+ int huge;
+ huge = shmem_parse_huge(value);
+ if (huge < 0)
+ goto bad_val;
+ if (!has_transparent_hugepage() &&
+ huge != SHMEM_HUGE_NEVER)
+ goto bad_val;
+ sbinfo->huge = huge;
+#endif
+#ifdef CONFIG_NUMA
} else if (!strcmp(this_char,"mpol")) {
mpol_put(mpol);
mpol = NULL;
if (mpol_parse_str(value, &mpol))
goto bad_val;
+#endif
} else {
pr_err("tmpfs: Bad mount option %s\n", this_char);
goto error;
goto out;
error = 0;
+ sbinfo->huge = config.huge;
sbinfo->max_blocks = config.max_blocks;
sbinfo->max_inodes = config.max_inodes;
sbinfo->free_inodes = config.max_inodes - inodes;
if (!gid_eq(sbinfo->gid, GLOBAL_ROOT_GID))
seq_printf(seq, ",gid=%u",
from_kgid_munged(&init_user_ns, sbinfo->gid));
+#ifdef CONFIG_TRANSPARENT_HUGEPAGE
+ /* Rightly or wrongly, show huge mount option unmasked by shmem_huge */
+ if (sbinfo->huge)
+ seq_printf(seq, ",huge=%s", shmem_format_huge(sbinfo->huge));
+#endif
shmem_show_mpol(seq, sbinfo->mpol);
return 0;
}
pr_err("Could not kern_mount tmpfs\n");
goto out1;
}
+
+#ifdef CONFIG_TRANSPARENT_HUGEPAGE
+ if (has_transparent_hugepage() && shmem_huge < SHMEM_HUGE_DENY)
+ SHMEM_SB(shm_mnt->mnt_sb)->huge = shmem_huge;
+ else
+ shmem_huge = 0; /* just in case it was patched */
+#endif
return 0;
out1:
return error;
}
+#if defined(CONFIG_TRANSPARENT_HUGEPAGE) && defined(CONFIG_SYSFS)
+static ssize_t shmem_enabled_show(struct kobject *kobj,
+ struct kobj_attribute *attr, char *buf)
+{
+ int values[] = {
+ SHMEM_HUGE_ALWAYS,
+ SHMEM_HUGE_WITHIN_SIZE,
+ SHMEM_HUGE_ADVISE,
+ SHMEM_HUGE_NEVER,
+ SHMEM_HUGE_DENY,
+ SHMEM_HUGE_FORCE,
+ };
+ int i, count;
+
+ for (i = 0, count = 0; i < ARRAY_SIZE(values); i++) {
+ const char *fmt = shmem_huge == values[i] ? "[%s] " : "%s ";
+
+ count += sprintf(buf + count, fmt,
+ shmem_format_huge(values[i]));
+ }
+ buf[count - 1] = '\n';
+ return count;
+}
+
+static ssize_t shmem_enabled_store(struct kobject *kobj,
+ struct kobj_attribute *attr, const char *buf, size_t count)
+{
+ char tmp[16];
+ int huge;
+
+ if (count + 1 > sizeof(tmp))
+ return -EINVAL;
+ memcpy(tmp, buf, count);
+ tmp[count] = '\0';
+ if (count && tmp[count - 1] == '\n')
+ tmp[count - 1] = '\0';
+
+ huge = shmem_parse_huge(tmp);
+ if (huge == -EINVAL)
+ return -EINVAL;
+ if (!has_transparent_hugepage() &&
+ huge != SHMEM_HUGE_NEVER && huge != SHMEM_HUGE_DENY)
+ return -EINVAL;
+
+ shmem_huge = huge;
+ if (shmem_huge < SHMEM_HUGE_DENY)
+ SHMEM_SB(shm_mnt->mnt_sb)->huge = shmem_huge;
+ return count;
+}
+
+struct kobj_attribute shmem_enabled_attr =
+ __ATTR(shmem_enabled, 0644, shmem_enabled_show, shmem_enabled_store);
+#endif /* CONFIG_TRANSPARENT_HUGEPAGE && CONFIG_SYSFS */
+
#else /* !CONFIG_SHMEM */
/*
projects / mirror_ubuntu-zesty-kernel.git / blobdiff