diff --git a/drivers/android/binderfs.c b/drivers/android/binderfs.c index 55c5adb87585..e54c99bc995f 100644 --- a/drivers/android/binderfs.c +++ b/drivers/android/binderfs.c @@ -51,18 +51,27 @@ static DEFINE_IDA(binderfs_minors); /** * binderfs_mount_opts - mount options for binderfs * @max: maximum number of allocatable binderfs binder devices + * @stats_mode: enable binder stats in binderfs. */ struct binderfs_mount_opts { int max; + int stats_mode; }; enum { Opt_max, + Opt_stats_mode, Opt_err }; +enum binderfs_stats_mode { + STATS_NONE, + STATS_GLOBAL, +}; + static const match_table_t tokens = { { Opt_max, "max=%d" }, + { Opt_stats_mode, "stats=%s" }, { Opt_err, NULL } }; @@ -290,8 +299,9 @@ static void binderfs_evict_inode(struct inode *inode) static int binderfs_parse_mount_opts(char *data, struct binderfs_mount_opts *opts) { - char *p; + char *p, *stats; opts->max = BINDERFS_MAX_MINOR; + opts->stats_mode = STATS_NONE; while ((p = strsep(&data, ",")) != NULL) { substring_t args[MAX_OPT_ARGS]; @@ -311,6 +321,22 @@ static int binderfs_parse_mount_opts(char *data, opts->max = max_devices; break; + case Opt_stats_mode: + if (!capable(CAP_SYS_ADMIN)) + return -EINVAL; + + stats = match_strdup(&args[0]); + if (!stats) + return -ENOMEM; + + if (strcmp(stats, "global") != 0) { + kfree(stats); + return -EINVAL; + } + + opts->stats_mode = STATS_GLOBAL; + kfree(stats); + break; default: pr_err("Invalid mount options\n"); return -EINVAL; @@ -322,8 +348,21 @@ static int binderfs_parse_mount_opts(char *data, static int binderfs_remount(struct super_block *sb, int *flags, char *data) { + int prev_stats_mode, ret; struct binderfs_info *info = sb->s_fs_info; - return binderfs_parse_mount_opts(data, &info->mount_opts); + + prev_stats_mode = info->mount_opts.stats_mode; + ret = binderfs_parse_mount_opts(data, &info->mount_opts); + if (ret) + return ret; + + if (prev_stats_mode != info->mount_opts.stats_mode) { + pr_err("Binderfs stats mode cannot be changed during a remount\n"); + info->mount_opts.stats_mode = prev_stats_mode; + return -EINVAL; + } + + return 0; } static int binderfs_show_mount_opts(struct seq_file *seq, struct dentry *root) @@ -333,6 +372,8 @@ static int binderfs_show_mount_opts(struct seq_file *seq, struct dentry *root) info = root->d_sb->s_fs_info; if (info->mount_opts.max <= BINDERFS_MAX_MINOR) seq_printf(seq, ",max=%d", info->mount_opts.max); + if (info->mount_opts.stats_mode == STATS_GLOBAL) + seq_printf(seq, ",stats=global"); return 0; }