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authorLinus Torvalds <torvalds@linux-foundation.org>2020-06-07 20:59:32 +0300
committerLinus Torvalds <torvalds@linux-foundation.org>2020-06-07 20:59:32 +0300
commit9aa900c8094dba7a60dc805ecec1e9f720744ba1 (patch)
tree3cc09a579f8ea6d3a182076ba722f7c1648e682d /drivers/char
parentf558b8364e19f9222e7976c64e9367f66bab02cc (diff)
parent05c8a4fc44a916dd897769ca69b42381f9177ec4 (diff)
downloadlinux-9aa900c8094dba7a60dc805ecec1e9f720744ba1.tar.xz
Merge tag 'char-misc-5.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc
Pull char/misc driver updates from Greg KH: "Here is the large set of char/misc driver patches for 5.8-rc1 Included in here are: - habanalabs driver updates, loads - mhi bus driver updates - extcon driver updates - clk driver updates (approved by the clock maintainer) - firmware driver updates - fpga driver updates - gnss driver updates - coresight driver updates - interconnect driver updates - parport driver updates (it's still alive!) - nvmem driver updates - soundwire driver updates - visorbus driver updates - w1 driver updates - various misc driver updates In short, loads of different driver subsystem updates along with the drivers as well. All have been in linux-next for a while with no reported issues" * tag 'char-misc-5.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (233 commits) habanalabs: correctly cast u64 to void* habanalabs: initialize variable to default value extcon: arizona: Fix runtime PM imbalance on error extcon: max14577: Add proper dt-compatible strings extcon: adc-jack: Fix an error handling path in 'adc_jack_probe()' extcon: remove redundant assignment to variable idx w1: omap-hdq: print dev_err if irq flags are not cleared w1: omap-hdq: fix interrupt handling which did show spurious timeouts w1: omap-hdq: fix return value to be -1 if there is a timeout w1: omap-hdq: cleanup to add missing newline for some dev_dbg /dev/mem: Revoke mappings when a driver claims the region misc: xilinx-sdfec: convert get_user_pages() --> pin_user_pages() misc: xilinx-sdfec: cleanup return value in xsdfec_table_write() misc: xilinx-sdfec: improve get_user_pages_fast() error handling nvmem: qfprom: remove incorrect write support habanalabs: handle MMU cache invalidation timeout habanalabs: don't allow hard reset with open processes habanalabs: GAUDI does not support soft-reset habanalabs: add print for soft reset due to event habanalabs: improve MMU cache invalidation code ...
Diffstat (limited to 'drivers/char')
-rw-r--r--drivers/char/mem.c101
-rw-r--r--drivers/char/tlclk.c17
2 files changed, 109 insertions, 9 deletions
diff --git a/drivers/char/mem.c b/drivers/char/mem.c
index 43dd0891ca1e..31cae88a730b 100644
--- a/drivers/char/mem.c
+++ b/drivers/char/mem.c
@@ -31,11 +31,15 @@
#include <linux/uio.h>
#include <linux/uaccess.h>
#include <linux/security.h>
+#include <linux/pseudo_fs.h>
+#include <uapi/linux/magic.h>
+#include <linux/mount.h>
#ifdef CONFIG_IA64
# include <linux/efi.h>
#endif
+#define DEVMEM_MINOR 1
#define DEVPORT_MINOR 4
static inline unsigned long size_inside_page(unsigned long start,
@@ -805,12 +809,64 @@ static loff_t memory_lseek(struct file *file, loff_t offset, int orig)
return ret;
}
+static struct inode *devmem_inode;
+
+#ifdef CONFIG_IO_STRICT_DEVMEM
+void revoke_devmem(struct resource *res)
+{
+ struct inode *inode = READ_ONCE(devmem_inode);
+
+ /*
+ * Check that the initialization has completed. Losing the race
+ * is ok because it means drivers are claiming resources before
+ * the fs_initcall level of init and prevent /dev/mem from
+ * establishing mappings.
+ */
+ if (!inode)
+ return;
+
+ /*
+ * The expectation is that the driver has successfully marked
+ * the resource busy by this point, so devmem_is_allowed()
+ * should start returning false, however for performance this
+ * does not iterate the entire resource range.
+ */
+ if (devmem_is_allowed(PHYS_PFN(res->start)) &&
+ devmem_is_allowed(PHYS_PFN(res->end))) {
+ /*
+ * *cringe* iomem=relaxed says "go ahead, what's the
+ * worst that can happen?"
+ */
+ return;
+ }
+
+ unmap_mapping_range(inode->i_mapping, res->start, resource_size(res), 1);
+}
+#endif
+
static int open_port(struct inode *inode, struct file *filp)
{
+ int rc;
+
if (!capable(CAP_SYS_RAWIO))
return -EPERM;
- return security_locked_down(LOCKDOWN_DEV_MEM);
+ rc = security_locked_down(LOCKDOWN_DEV_MEM);
+ if (rc)
+ return rc;
+
+ if (iminor(inode) != DEVMEM_MINOR)
+ return 0;
+
+ /*
+ * Use a unified address space to have a single point to manage
+ * revocations when drivers want to take over a /dev/mem mapped
+ * range.
+ */
+ inode->i_mapping = devmem_inode->i_mapping;
+ filp->f_mapping = inode->i_mapping;
+
+ return 0;
}
#define zero_lseek null_lseek
@@ -885,7 +941,7 @@ static const struct memdev {
fmode_t fmode;
} devlist[] = {
#ifdef CONFIG_DEVMEM
- [1] = { "mem", 0, &mem_fops, FMODE_UNSIGNED_OFFSET },
+ [DEVMEM_MINOR] = { "mem", 0, &mem_fops, FMODE_UNSIGNED_OFFSET },
#endif
#ifdef CONFIG_DEVKMEM
[2] = { "kmem", 0, &kmem_fops, FMODE_UNSIGNED_OFFSET },
@@ -939,6 +995,45 @@ static char *mem_devnode(struct device *dev, umode_t *mode)
static struct class *mem_class;
+static int devmem_fs_init_fs_context(struct fs_context *fc)
+{
+ return init_pseudo(fc, DEVMEM_MAGIC) ? 0 : -ENOMEM;
+}
+
+static struct file_system_type devmem_fs_type = {
+ .name = "devmem",
+ .owner = THIS_MODULE,
+ .init_fs_context = devmem_fs_init_fs_context,
+ .kill_sb = kill_anon_super,
+};
+
+static int devmem_init_inode(void)
+{
+ static struct vfsmount *devmem_vfs_mount;
+ static int devmem_fs_cnt;
+ struct inode *inode;
+ int rc;
+
+ rc = simple_pin_fs(&devmem_fs_type, &devmem_vfs_mount, &devmem_fs_cnt);
+ if (rc < 0) {
+ pr_err("Cannot mount /dev/mem pseudo filesystem: %d\n", rc);
+ return rc;
+ }
+
+ inode = alloc_anon_inode(devmem_vfs_mount->mnt_sb);
+ if (IS_ERR(inode)) {
+ rc = PTR_ERR(inode);
+ pr_err("Cannot allocate inode for /dev/mem: %d\n", rc);
+ simple_release_fs(&devmem_vfs_mount, &devmem_fs_cnt);
+ return rc;
+ }
+
+ /* publish /dev/mem initialized */
+ WRITE_ONCE(devmem_inode, inode);
+
+ return 0;
+}
+
static int __init chr_dev_init(void)
{
int minor;
@@ -960,6 +1055,8 @@ static int __init chr_dev_init(void)
*/
if ((minor == DEVPORT_MINOR) && !arch_has_dev_port())
continue;
+ if ((minor == DEVMEM_MINOR) && devmem_init_inode() != 0)
+ continue;
device_create(mem_class, NULL, MKDEV(MEM_MAJOR, minor),
NULL, devlist[minor].name);
diff --git a/drivers/char/tlclk.c b/drivers/char/tlclk.c
index 6d81bb3bb503..896a3550fba9 100644
--- a/drivers/char/tlclk.c
+++ b/drivers/char/tlclk.c
@@ -777,17 +777,21 @@ static int __init tlclk_init(void)
{
int ret;
+ telclk_interrupt = (inb(TLCLK_REG7) & 0x0f);
+
+ alarm_events = kzalloc( sizeof(struct tlclk_alarms), GFP_KERNEL);
+ if (!alarm_events) {
+ ret = -ENOMEM;
+ goto out1;
+ }
+
ret = register_chrdev(tlclk_major, "telco_clock", &tlclk_fops);
if (ret < 0) {
printk(KERN_ERR "tlclk: can't get major %d.\n", tlclk_major);
+ kfree(alarm_events);
return ret;
}
tlclk_major = ret;
- alarm_events = kzalloc( sizeof(struct tlclk_alarms), GFP_KERNEL);
- if (!alarm_events) {
- ret = -ENOMEM;
- goto out1;
- }
/* Read telecom clock IRQ number (Set by BIOS) */
if (!request_region(TLCLK_BASE, 8, "telco_clock")) {
@@ -796,7 +800,6 @@ static int __init tlclk_init(void)
ret = -EBUSY;
goto out2;
}
- telclk_interrupt = (inb(TLCLK_REG7) & 0x0f);
if (0x0F == telclk_interrupt ) { /* not MCPBL0010 ? */
printk(KERN_ERR "telclk_interrupt = 0x%x non-mcpbl0010 hw.\n",
@@ -837,8 +840,8 @@ out3:
release_region(TLCLK_BASE, 8);
out2:
kfree(alarm_events);
-out1:
unregister_chrdev(tlclk_major, "telco_clock");
+out1:
return ret;
}