path: root/drivers/char
diff options
authorLinus Torvalds <torvalds@linux-foundation.org>2013-11-13 15:45:43 +0900
committerLinus Torvalds <torvalds@linux-foundation.org>2013-11-13 15:45:43 +0900
commit5cbb3d216e2041700231bcfc383ee5f8b7fc8b74 (patch)
treea738fa82dbcefa9bd283c08bc67f38827be63937 /drivers/char
parent9bc9ccd7db1c9f043f75380b5a5b94912046a60e (diff)
parent4e9b45a19241354daec281d7a785739829b52359 (diff)
Merge branch 'akpm' (patches from Andrew Morton)
Merge first patch-bomb from Andrew Morton: "Quite a lot of other stuff is banked up awaiting further next->mainline merging, but this batch contains: - Lots of random misc patches - OCFS2 - Most of MM - backlight updates - lib/ updates - printk updates - checkpatch updates - epoll tweaking - rtc updates - hfs - hfsplus - documentation - procfs - update gcov to gcc-4.7 format - IPC" * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (269 commits) ipc, msg: fix message length check for negative values ipc/util.c: remove unnecessary work pending test devpts: plug the memory leak in kill_sb ./Makefile: export initial ramdisk compression config option init/Kconfig: add option to disable kernel compression drivers: w1: make w1_slave::flags long to avoid memory corruption drivers/w1/masters/ds1wm.cuse dev_get_platdata() drivers/memstick/core/ms_block.c: fix unreachable state in h_msb_read_page() drivers/memstick/core/mspro_block.c: fix attributes array allocation drivers/pps/clients/pps-gpio.c: remove redundant of_match_ptr kernel/panic.c: reduce 1 byte usage for print tainted buffer gcov: reuse kbasename helper kernel/gcov/fs.c: use pr_warn() kernel/module.c: use pr_foo() gcov: compile specific gcov implementation based on gcc version gcov: add support for gcc 4.7 gcov format gcov: move gcov structs definitions to a gcc version specific file kernel/taskstats.c: return -ENOMEM when alloc memory fails in add_del_listener() kernel/taskstats.c: add nla_nest_cancel() for failure processing between nla_nest_start() and nla_nest_end() kernel/sysctl_binary.c: use scnprintf() instead of snprintf() ...
Diffstat (limited to 'drivers/char')
2 files changed, 30 insertions, 4 deletions
diff --git a/drivers/char/Kconfig b/drivers/char/Kconfig
index 14219972c745..fa3243d71c76 100644
--- a/drivers/char/Kconfig
+++ b/drivers/char/Kconfig
@@ -522,10 +522,16 @@ config HPET_MMAP
If you say Y here, user applications will be able to mmap
the HPET registers.
+ bool "Enable HPET MMAP access by default"
+ default y
+ depends on HPET_MMAP
+ help
In some hardware implementations, the page containing HPET
registers may also contain other things that shouldn't be
- exposed to the user. If this applies to your hardware,
- say N here.
+ exposed to the user. This option selects the default (if
+ kernel parameter hpet_mmap is not set) user access to the
+ registers for applications that require it.
tristate "Hangcheck timer"
diff --git a/drivers/char/hpet.c b/drivers/char/hpet.c
index dca5834685cf..5d9c31dfc905 100644
--- a/drivers/char/hpet.c
+++ b/drivers/char/hpet.c
@@ -367,12 +367,29 @@ static unsigned int hpet_poll(struct file *file, poll_table * wait)
return 0;
+static int hpet_mmap_enabled = 1;
+static int hpet_mmap_enabled = 0;
+static __init int hpet_mmap_enable(char *str)
+ get_option(&str, &hpet_mmap_enabled);
+ pr_info("HPET mmap %s\n", hpet_mmap_enabled ? "enabled" : "disabled");
+ return 1;
+__setup("hpet_mmap", hpet_mmap_enable);
static int hpet_mmap(struct file *file, struct vm_area_struct *vma)
struct hpet_dev *devp;
unsigned long addr;
+ if (!hpet_mmap_enabled)
+ return -EACCES;
devp = file->private_data;
addr = devp->hd_hpets->hp_hpet_phys;
@@ -381,10 +398,13 @@ static int hpet_mmap(struct file *file, struct vm_area_struct *vma)
vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
return vm_iomap_memory(vma, addr, PAGE_SIZE);
+static int hpet_mmap(struct file *file, struct vm_area_struct *vma)
return -ENOSYS;
static int hpet_fasync(int fd, struct file *file, int on)