1. 06 2月, 2008 40 次提交
    • M
      pm qos infrastructure and interface · d82b3518
      Mark Gross 提交于
      The following patch is a generalization of the latency.c implementation done
      by Arjan last year.  It provides infrastructure for more than one parameter,
      and exposes a user mode interface for processes to register pm_qos
      expectations of processes.
      
      This interface provides a kernel and user mode interface for registering
      performance expectations by drivers, subsystems and user space applications on
      one of the parameters.
      
      Currently we have {cpu_dma_latency, network_latency, network_throughput} as
      the initial set of pm_qos parameters.
      
      The infrastructure exposes multiple misc device nodes one per implemented
      parameter.  The set of parameters implement is defined by pm_qos_power_init()
      and pm_qos_params.h.  This is done because having the available parameters
      being runtime configurable or changeable from a driver was seen as too easy to
      abuse.
      
      For each parameter a list of performance requirements is maintained along with
      an aggregated target value.  The aggregated target value is updated with
      changes to the requirement list or elements of the list.  Typically the
      aggregated target value is simply the max or min of the requirement values
      held in the parameter list elements.
      
      >From kernel mode the use of this interface is simple:
      
      pm_qos_add_requirement(param_id, name, target_value):
      
        Will insert a named element in the list for that identified PM_QOS
        parameter with the target value.  Upon change to this list the new target is
        recomputed and any registered notifiers are called only if the target value
        is now different.
      
      pm_qos_update_requirement(param_id, name, new_target_value):
      
        Will search the list identified by the param_id for the named list element
        and then update its target value, calling the notification tree if the
        aggregated target is changed.  with that name is already registered.
      
      pm_qos_remove_requirement(param_id, name):
      
        Will search the identified list for the named element and remove it, after
        removal it will update the aggregate target and call the notification tree
        if the target was changed as a result of removing the named requirement.
      
      >From user mode:
      
        Only processes can register a pm_qos requirement.  To provide for
        automatic cleanup for process the interface requires the process to register
        its parameter requirements in the following way:
      
        To register the default pm_qos target for the specific parameter, the
        process must open one of /dev/[cpu_dma_latency, network_latency,
        network_throughput]
      
        As long as the device node is held open that process has a registered
        requirement on the parameter.  The name of the requirement is
        "process_<PID>" derived from the current->pid from within the open system
        call.
      
        To change the requested target value the process needs to write a s32
        value to the open device node.  This translates to a
        pm_qos_update_requirement call.
      
        To remove the user mode request for a target value simply close the device
        node.
      
      [akpm@linux-foundation.org: fix warnings]
      [akpm@linux-foundation.org: fix build]
      [akpm@linux-foundation.org: fix build again]
      [akpm@linux-foundation.org: coding-style fixes]
      Signed-off-by: Nmark gross <mgross@linux.intel.com>
      Cc: "John W. Linville" <linville@tuxdriver.com>
      Cc: Len Brown <lenb@kernel.org>
      Cc: Jaroslav Kysela <perex@suse.cz>
      Cc: Takashi Iwai <tiwai@suse.de>
      Cc: Arjan van de Ven <arjan@infradead.org>
      Cc: Venki Pallipadi <venkatesh.pallipadi@intel.com>
      Cc: Adam Belay <abelay@novell.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      d82b3518
    • A
      make kernel_shutdown_prepare() static · 4ef7229f
      Adrian Bunk 提交于
      kernel_shutdown_prepare() can now become static.
      Signed-off-by: NAdrian Bunk <bunk@kernel.org>
      Acked-by: NPavel Machek <pavel@ucw.cz>
      Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      4ef7229f
    • A
      kernel/power/disk.c: make code static · 47a460d5
      Adrian Bunk 提交于
      resume_file[] and create_image() can become static.
      Signed-off-by: NAdrian Bunk <bunk@kernel.org>
      Acked-by: NPavel Machek <pavel@ucw.cz>
      Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      47a460d5
    • A
      alpha: fix warning by fixing flush_tlb_kernel_range() · cbed6c6e
      Andrew Morton 提交于
      mm/vmalloc.c: In function 'unmap_kernel_range':
      mm/vmalloc.c:75: warning: unused variable 'start'
      
      Macros are so horrid.
      
      Cc: Richard Henderson <rth@twiddle.net>
      Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      cbed6c6e
    • N
      agp: alpha nopage · 6d6f8d52
      Nick Piggin 提交于
      Convert AGP alpha driver from nopage to fault.
      NULL is NOPAGE_SIGBUS, so we aren't changing behaviour there.
      Signed-off-by: NNick Piggin <npiggin@suse.de>
      Cc: Richard Henderson <rth@twiddle.net>
      Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      6d6f8d52
    • S
      Alpha doesn't use socketcall · 2f78dcfd
      Samuel Thibault 提交于
      Alpha doesn't use socketcall and doesn't provide __NR_socketcall.
      Signed-off-by: NSamuel Thibault <samuel.thibault@citrix.com>
      Cc: Richard Henderson <rth@twiddle.net>
      Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      2f78dcfd
    • F
      alpha: kill deprecated virt_to_bus · fd2e2633
      FUJITA Tomonori 提交于
      pci-noop.c doesn't use DMA mappings.
      Signed-off-by: NFUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
      Cc: Jens Axboe <jens.axboe@oracle.com>
      Cc: Richard Henderson <rth@twiddle.net>
      Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      fd2e2633
    • A
      alpha: atomic_add_return() should return int · 26a6e661
      Andrew Morton 提交于
      Prevents stuff like
      
      drivers/crypto/hifn_795x.c:2443: warning: format '%d' expects type 'int', but argument 4 has type 'long int'
      drivers/crypto/hifn_795x.c:2443: warning: format '%d' expects type 'int', but argument 4 has type 'long int'
      
      (at least).
      
      Cc: Richard Henderson <rth@twiddle.net>
      Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      26a6e661
    • L
      arch/alpha: remove duplicate includes · e820ce72
      Lucas Woods 提交于
      Signed-off-by: NLucas Woods <woodzy@gmail.com>
      Cc: Richard Henderson <rth@twiddle.net>
      Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      e820ce72
    • A
      m68knommu: remove duplicate exports · 49eaf7d7
      Adrian Bunk 提交于
      One EXPORT_SYMBOL should be enough for everyone.
      Signed-off-by: NAdrian Bunk <bunk@kernel.org>
      Acked-by: NGreg Ungerer <gerg@uclinux.org>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      49eaf7d7
    • P
      nommu: add new vmalloc_user() and remap_vmalloc_range() interfaces. · f905bc44
      Paul Mundt 提交于
      This builds on top of the earlier vmalloc_32_user() work introduced by
      b5073173, as we now have places in the nommu
      allmodconfig that hit up against these missing APIs.
      
      As vmalloc_32_user() is already implemented, this is moved over to
      vmalloc_user() and simply made a wrapper.  As all current nommu platforms are
      32-bit addressable, there's no special casing we have to do for ZONE_DMA and
      things of that nature as per GFP_VMALLOC32.
      
      remap_vmalloc_range() needs to check VM_USERMAP in order to figure out whether
      we permit the remap or not, which means that we also have to rework the
      vmalloc_user() code to grovel for the VMA and set the flag.
      Signed-off-by: NPaul Mundt <lethal@linux-sh.org>
      Acked-by: NDavid McCullough <david_mccullough@securecomputing.com>
      Acked-by: NDavid Howells <dhowells@redhat.com>
      Acked-by: NGreg Ungerer <gerg@snapgear.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      f905bc44
    • J
      m68knommu: removing config variable DUMPTOFLASH · f156ac8c
      Jiri Olsa 提交于
      Removing config variable DUMPTOFLASH, since it is not used
      Signed-off-by: NJiri Olsa <olsajiri@gmail.com>
      Acked-by: NGreg Ungerer <gerg@snapgear.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      f156ac8c
    • J
      m68knomu: remove dead config symbols from m68knomu code · c155f3f9
      Jiri Olsa 提交于
      remove dead config symbols from m68knommu code
      Signed-off-by: NJiri Olsa <olsajiri@gmail.com>
      Acked-by: NGreg Ungerer <gerg@snapgear.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      c155f3f9
    • G
      m68knommu: use ARRAY_SIZE in ColdFire serial driver · 16791963
      Greg Ungerer 提交于
      Use ARRAY_SIZE macroto get maximum ports in ColdFire serial driver.
      Signed-off-by: NGreg Ungerer <gerg@uclinux.org>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      16791963
    • P
      frv: use find_task_by_vpid in cxn_pin_by_pid · 540e3102
      Pavel Emelyanov 提交于
      The function is question gets the pid from sysctl table, so this one is a
      virtual pid, i.e.  the pid of a task as it is seen from inside a namespace.
      
      So the find_task_by_vpid() must be used here.
      Signed-off-by: NPavel Emelyanov <xemul@openvz.org>
      Cc: "Eric W. Biederman" <ebiederm@xmission.com>
      Cc: David Howells <dhowells@redhat.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      540e3102
    • J
      frv: remove dead config symbol from FRV code · 8c5900b2
      Jiri Olsa 提交于
      Remove dead config symbol from FRV code.
      Signed-off-by: NJiri Olsa <olsajiri@gmail.com>
      Acked-by: NDavid Howells <dhowells@redhat.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      8c5900b2
    • R
      FRV: move DMA macros to scatterlist.h for consistency. · 82b12e23
      Robert P. J. Day 提交于
      To be consistent with other architectures, these two DMA macros should
      be defined in scatterlist.h as opposed to dma-mapping.h
      Signed-off-by: NRobert P. J. Day <rpjday@crashcourse.ca>
      Acked-by: NDavid Howells <dhowells@redhat.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      82b12e23
    • D
      FRV: permit the memory to be located elsewhere in NOMMU mode · 7038220a
      David Howells 提交于
      Permit the memory to be located somewhere other than address 0xC0000000 in
      NOMMU mode.  The configuration options are already present, it just
      requires wiring up in the linker script.
      
      Note that only a limited set of locations of runtime addresses are available
      because of the way the CPU protection registers work.
      Signed-off-by: NDavid Howells <dhowells@redhat.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      7038220a
    • C
      Smack: Simplified Mandatory Access Control Kernel · e114e473
      Casey Schaufler 提交于
      Smack is the Simplified Mandatory Access Control Kernel.
      
      Smack implements mandatory access control (MAC) using labels
      attached to tasks and data containers, including files, SVIPC,
      and other tasks. Smack is a kernel based scheme that requires
      an absolute minimum of application support and a very small
      amount of configuration data.
      
      Smack uses extended attributes and
      provides a set of general mount options, borrowing technics used
      elsewhere. Smack uses netlabel for CIPSO labeling. Smack provides
      a pseudo-filesystem smackfs that is used for manipulation of
      system Smack attributes.
      
      The patch, patches for ls and sshd, a README, a startup script,
      and x86 binaries for ls and sshd are also available on
      
          http://www.schaufler-ca.com
      
      Development has been done using Fedora Core 7 in a virtual machine
      environment and on an old Sony laptop.
      
      Smack provides mandatory access controls based on the label attached
      to a task and the label attached to the object it is attempting to
      access. Smack labels are deliberately short (1-23 characters) text
      strings. Single character labels using special characters are reserved
      for system use. The only operation applied to Smack labels is equality
      comparison. No wildcards or expressions, regular or otherwise, are
      used. Smack labels are composed of printable characters and may not
      include "/".
      
      A file always gets the Smack label of the task that created it.
      
      Smack defines and uses these labels:
      
          "*" - pronounced "star"
          "_" - pronounced "floor"
          "^" - pronounced "hat"
          "?" - pronounced "huh"
      
      The access rules enforced by Smack are, in order:
      
      1. Any access requested by a task labeled "*" is denied.
      2. A read or execute access requested by a task labeled "^"
         is permitted.
      3. A read or execute access requested on an object labeled "_"
         is permitted.
      4. Any access requested on an object labeled "*" is permitted.
      5. Any access requested by a task on an object with the same
         label is permitted.
      6. Any access requested that is explicitly defined in the loaded
         rule set is permitted.
      7. Any other access is denied.
      
      Rules may be explicitly defined by writing subject,object,access
      triples to /smack/load.
      
      Smack rule sets can be easily defined that describe Bell&LaPadula
      sensitivity, Biba integrity, and a variety of interesting
      configurations. Smack rule sets can be modified on the fly to
      accommodate changes in the operating environment or even the time
      of day.
      
      Some practical use cases:
      
      Hierarchical levels. The less common of the two usual uses
      for MLS systems is to define hierarchical levels, often
      unclassified, confidential, secret, and so on. To set up smack
      to support this, these rules could be defined:
      
         C        Unclass rx
         S        C       rx
         S        Unclass rx
         TS       S       rx
         TS       C       rx
         TS       Unclass rx
      
      A TS process can read S, C, and Unclass data, but cannot write it.
      An S process can read C and Unclass. Note that specifying that
      TS can read S and S can read C does not imply TS can read C, it
      has to be explicitly stated.
      
      Non-hierarchical categories. This is the more common of the
      usual uses for an MLS system. Since the default rule is that a
      subject cannot access an object with a different label no
      access rules are required to implement compartmentalization.
      
      A case that the Bell & LaPadula policy does not allow is demonstrated
      with this Smack access rule:
      
      A case that Bell&LaPadula does not allow that Smack does:
      
          ESPN    ABC   r
          ABC     ESPN  r
      
      On my portable video device I have two applications, one that
      shows ABC programming and the other ESPN programming. ESPN wants
      to show me sport stories that show up as news, and ABC will
      only provide minimal information about a sports story if ESPN
      is covering it. Each side can look at the other's info, neither
      can change the other. Neither can see what FOX is up to, which
      is just as well all things considered.
      
      Another case that I especially like:
      
          SatData Guard   w
          Guard   Publish w
      
      A program running with the Guard label opens a UDP socket and
      accepts messages sent by a program running with a SatData label.
      The Guard program inspects the message to ensure it is wholesome
      and if it is sends it to a program running with the Publish label.
      This program then puts the information passed in an appropriate
      place. Note that the Guard program cannot write to a Publish
      file system object because file system semanitic require read as
      well as write.
      
      The four cases (categories, levels, mutual read, guardbox) here
      are all quite real, and problems I've been asked to solve over
      the years. The first two are easy to do with traditonal MLS systems
      while the last two you can't without invoking privilege, at least
      for a while.
      Signed-off-by: NCasey Schaufler <casey@schaufler-ca.com>
      Cc: Joshua Brindle <method@manicmethod.com>
      Cc: Paul Moore <paul.moore@hp.com>
      Cc: Stephen Smalley <sds@tycho.nsa.gov>
      Cc: Chris Wright <chrisw@sous-sol.org>
      Cc: James Morris <jmorris@namei.org>
      Cc: "Ahmed S. Darwish" <darwish.07@gmail.com>
      Cc: Andrew G. Morgan <morgan@kernel.org>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      e114e473
    • P
      NetLabel: introduce a new kernel configuration API for NetLabel · eda61d32
      Paul Moore 提交于
      Add a new set of configuration functions to the NetLabel/LSM API so that
      LSMs can perform their own configuration of the NetLabel subsystem without
      relying on assistance from userspace.
      Signed-off-by: NPaul Moore <paul.moore@hp.com>
      Signed-off-by: NCasey Schaufler <casey@schaufler-ca.com>
      Reviewed-by: NJames Morris <jmorris@namei.org>
      Cc: Chris Wright <chrisw@sous-sol.org>
      Cc: Stephen Smalley <sds@tycho.nsa.gov>
      Cc: Casey Schaufler <casey@schaufler-ca.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      eda61d32
    • S
      oom_kill: remove uid==0 checks · 97829955
      Serge E. Hallyn 提交于
      Root processes are considered more important when out of memory and killing
      proceses.  The check for CAP_SYS_ADMIN was augmented with a check for
      uid==0 or euid==0.
      
      There are several possible ways to look at this:
      
      	1. uid comparisons are unnecessary, trust CAP_SYS_ADMIN
      	   alone.  However CAP_SYS_RESOURCE is the one that really
      	   means "give me extra resources" so allow for that as
      	   well.
      	2. Any privileged code should be protected, but uid is not
      	   an indication of privilege.  So we should check whether
      	   any capabilities are raised.
      	3. uid==0 makes processes on the host as well as in containers
      	   more important, so we should keep the existing checks.
      	4. uid==0 makes processes only on the host more important,
      	   even without any capabilities.  So we should be keeping
      	   the (uid==0||euid==0) check but only when
      	   userns==&init_user_ns.
      
      I'm following number 1 here.
      Signed-off-by: NSerge Hallyn <serue@us.ibm.com>
      Cc: Andrew Morgan <morgan@kernel.org>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      97829955
    • S
      capabilities: introduce per-process capability bounding set · 3b7391de
      Serge E. Hallyn 提交于
      The capability bounding set is a set beyond which capabilities cannot grow.
       Currently cap_bset is per-system.  It can be manipulated through sysctl,
      but only init can add capabilities.  Root can remove capabilities.  By
      default it includes all caps except CAP_SETPCAP.
      
      This patch makes the bounding set per-process when file capabilities are
      enabled.  It is inherited at fork from parent.  Noone can add elements,
      CAP_SETPCAP is required to remove them.
      
      One example use of this is to start a safer container.  For instance, until
      device namespaces or per-container device whitelists are introduced, it is
      best to take CAP_MKNOD away from a container.
      
      The bounding set will not affect pP and pE immediately.  It will only
      affect pP' and pE' after subsequent exec()s.  It also does not affect pI,
      and exec() does not constrain pI'.  So to really start a shell with no way
      of regain CAP_MKNOD, you would do
      
      	prctl(PR_CAPBSET_DROP, CAP_MKNOD);
      	cap_t cap = cap_get_proc();
      	cap_value_t caparray[1];
      	caparray[0] = CAP_MKNOD;
      	cap_set_flag(cap, CAP_INHERITABLE, 1, caparray, CAP_DROP);
      	cap_set_proc(cap);
      	cap_free(cap);
      
      The following test program will get and set the bounding
      set (but not pI).  For instance
      
      	./bset get
      		(lists capabilities in bset)
      	./bset drop cap_net_raw
      		(starts shell with new bset)
      		(use capset, setuid binary, or binary with
      		file capabilities to try to increase caps)
      
      ************************************************************
      cap_bound.c
      ************************************************************
       #include <sys/prctl.h>
       #include <linux/capability.h>
       #include <sys/types.h>
       #include <unistd.h>
       #include <stdio.h>
       #include <stdlib.h>
       #include <string.h>
      
       #ifndef PR_CAPBSET_READ
       #define PR_CAPBSET_READ 23
       #endif
      
       #ifndef PR_CAPBSET_DROP
       #define PR_CAPBSET_DROP 24
       #endif
      
      int usage(char *me)
      {
      	printf("Usage: %s get\n", me);
      	printf("       %s drop <capability>\n", me);
      	return 1;
      }
      
       #define numcaps 32
      char *captable[numcaps] = {
      	"cap_chown",
      	"cap_dac_override",
      	"cap_dac_read_search",
      	"cap_fowner",
      	"cap_fsetid",
      	"cap_kill",
      	"cap_setgid",
      	"cap_setuid",
      	"cap_setpcap",
      	"cap_linux_immutable",
      	"cap_net_bind_service",
      	"cap_net_broadcast",
      	"cap_net_admin",
      	"cap_net_raw",
      	"cap_ipc_lock",
      	"cap_ipc_owner",
      	"cap_sys_module",
      	"cap_sys_rawio",
      	"cap_sys_chroot",
      	"cap_sys_ptrace",
      	"cap_sys_pacct",
      	"cap_sys_admin",
      	"cap_sys_boot",
      	"cap_sys_nice",
      	"cap_sys_resource",
      	"cap_sys_time",
      	"cap_sys_tty_config",
      	"cap_mknod",
      	"cap_lease",
      	"cap_audit_write",
      	"cap_audit_control",
      	"cap_setfcap"
      };
      
      int getbcap(void)
      {
      	int comma=0;
      	unsigned long i;
      	int ret;
      
      	printf("i know of %d capabilities\n", numcaps);
      	printf("capability bounding set:");
      	for (i=0; i<numcaps; i++) {
      		ret = prctl(PR_CAPBSET_READ, i);
      		if (ret < 0)
      			perror("prctl");
      		else if (ret==1)
      			printf("%s%s", (comma++) ? ", " : " ", captable[i]);
      	}
      	printf("\n");
      	return 0;
      }
      
      int capdrop(char *str)
      {
      	unsigned long i;
      
      	int found=0;
      	for (i=0; i<numcaps; i++) {
      		if (strcmp(captable[i], str) == 0) {
      			found=1;
      			break;
      		}
      	}
      	if (!found)
      		return 1;
      	if (prctl(PR_CAPBSET_DROP, i)) {
      		perror("prctl");
      		return 1;
      	}
      	return 0;
      }
      
      int main(int argc, char *argv[])
      {
      	if (argc<2)
      		return usage(argv[0]);
      	if (strcmp(argv[1], "get")==0)
      		return getbcap();
      	if (strcmp(argv[1], "drop")!=0 || argc<3)
      		return usage(argv[0]);
      	if (capdrop(argv[2])) {
      		printf("unknown capability\n");
      		return 1;
      	}
      	return execl("/bin/bash", "/bin/bash", NULL);
      }
      ************************************************************
      
      [serue@us.ibm.com: fix typo]
      Signed-off-by: NSerge E. Hallyn <serue@us.ibm.com>
      Signed-off-by: NAndrew G. Morgan <morgan@kernel.org>
      Cc: Stephen Smalley <sds@tycho.nsa.gov>
      Cc: James Morris <jmorris@namei.org>
      Cc: Chris Wright <chrisw@sous-sol.org>
      Cc: Casey Schaufler <casey@schaufler-ca.com>a
      Signed-off-by: N"Serge E. Hallyn" <serue@us.ibm.com>
      Tested-by: NJiri Slaby <jirislaby@gmail.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      3b7391de
    • A
      Remove unnecessary include from include/linux/capability.h · 46c383cc
      Andrew Morgan 提交于
      KaiGai Kohei observed that this line in the linux header is not needed.
      Signed-off-by: NAndrew G. Morgan <morgan@kernel.org>
      Cc: KaiGai Kohei <kaigai@kaigai.gr.jp>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      46c383cc
    • A
      Add 64-bit capability support to the kernel · e338d263
      Andrew Morgan 提交于
      The patch supports legacy (32-bit) capability userspace, and where possible
      translates 32-bit capabilities to/from userspace and the VFS to 64-bit
      kernel space capabilities.  If a capability set cannot be compressed into
      32-bits for consumption by user space, the system call fails, with -ERANGE.
      
      FWIW libcap-2.00 supports this change (and earlier capability formats)
      
       http://www.kernel.org/pub/linux/libs/security/linux-privs/kernel-2.6/
      
      [akpm@linux-foundation.org: coding-syle fixes]
      [akpm@linux-foundation.org: use get_task_comm()]
      [ezk@cs.sunysb.edu: build fix]
      [akpm@linux-foundation.org: do not initialise statics to 0 or NULL]
      [akpm@linux-foundation.org: unused var]
      [serue@us.ibm.com: export __cap_ symbols]
      Signed-off-by: NAndrew G. Morgan <morgan@kernel.org>
      Cc: Stephen Smalley <sds@tycho.nsa.gov>
      Acked-by: NSerge Hallyn <serue@us.ibm.com>
      Cc: Chris Wright <chrisw@sous-sol.org>
      Cc: James Morris <jmorris@namei.org>
      Cc: Casey Schaufler <casey@schaufler-ca.com>
      Signed-off-by: NErez Zadok <ezk@cs.sunysb.edu>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      e338d263
    • A
      revert "capabilities: clean up file capability reading" · 8f6936f4
      Andrew Morton 提交于
      Revert b68680e4 to make way for the next
      patch: "Add 64-bit capability support to the kernel".
      
      We want to keep the vfs_cap_data.data[] structure, using two 'data's for
      64-bit caps (and later three for 96-bit caps), whereas
      b68680e4 had gotten rid of the 'data' struct
      made its members inline.
      
      The 64-bit caps patch keeps the stack abuse fix at get_file_caps(), which was
      the more important part of that patch.
      
      [akpm@linux-foundation.org: coding-style fixes]
      Cc: Stephen Smalley <sds@tycho.nsa.gov>
      Cc: Serge Hallyn <serue@us.ibm.com>
      Cc: Chris Wright <chrisw@sous-sol.org>
      Cc: James Morris <jmorris@namei.org>
      Cc: Casey Schaufler <casey@schaufler-ca.com>
      Cc: Andrew Morgan <morgan@kernel.org>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      8f6936f4
    • D
      VFS: Reorder vfs_getxattr to avoid unnecessary calls to the LSM · 4bea5805
      David P. Quigley 提交于
      Originally vfs_getxattr would pull the security xattr variable using
      the inode getxattr handle and then proceed to clobber it with a subsequent call
      to the LSM.
      
      This patch reorders the two operations such that when the xattr requested is
      in the security namespace it first attempts to grab the value from the LSM
      directly.
      
      If it fails to obtain the value because there is no module present or the
      module does not support the operation it will fall back to using the inode
      getxattr operation.
      
      In the event that both are inaccessible it returns EOPNOTSUPP.
      Signed-off-by: NDavid P. Quigley <dpquigl@tycho.nsa.gov>
      Cc: Stephen Smalley <sds@tycho.nsa.gov>
      Cc: Chris Wright <chrisw@sous-sol.org>
      Acked-by: NJames Morris <jmorris@namei.org>
      Acked-by: NSerge Hallyn <serue@us.ibm.com>
      Cc: Casey Schaufler <casey@schaufler-ca.com>
      Cc: Al Viro <viro@zeniv.linux.org.uk>
      Cc: Christoph Hellwig <hch@lst.de>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      4bea5805
    • D
      VFS/Security: Rework inode_getsecurity and callers to return resulting buffer · 42492594
      David P. Quigley 提交于
      This patch modifies the interface to inode_getsecurity to have the function
      return a buffer containing the security blob and its length via parameters
      instead of relying on the calling function to give it an appropriately sized
      buffer.
      
      Security blobs obtained with this function should be freed using the
      release_secctx LSM hook.  This alleviates the problem of the caller having to
      guess a length and preallocate a buffer for this function allowing it to be
      used elsewhere for Labeled NFS.
      
      The patch also removed the unused err parameter.  The conversion is similar to
      the one performed by Al Viro for the security_getprocattr hook.
      Signed-off-by: NDavid P. Quigley <dpquigl@tycho.nsa.gov>
      Cc: Stephen Smalley <sds@tycho.nsa.gov>
      Cc: Chris Wright <chrisw@sous-sol.org>
      Acked-by: NJames Morris <jmorris@namei.org>
      Acked-by: NSerge Hallyn <serue@us.ibm.com>
      Cc: Casey Schaufler <casey@schaufler-ca.com>
      Cc: Al Viro <viro@zeniv.linux.org.uk>
      Cc: Christoph Hellwig <hch@lst.de>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      42492594
    • M
      37291458
    • M
      slob: reduce external fragmentation by using three free lists · 20cecbae
      Matt Mackall 提交于
      By putting smaller objects on their own list, we greatly reduce overall
      external fragmentation and increase repeatability.  This reduces total SLOB
      overhead from > 50% to ~6% on a simple boot test.
      Signed-off-by: NMatt Mackall <mpm@selenic.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      20cecbae
    • M
      slob: fix free block merging at head of subpage · 679299b3
      Matt Mackall 提交于
      We weren't merging freed blocks at the beginning of the free list.  Fixing
      this showed a 2.5% efficiency improvement in a userspace test harness.
      Signed-off-by: NMatt Mackall <mpm@selenic.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      679299b3
    • F
      writeback: speed up writeback of big dirty files · 8bc3be27
      Fengguang Wu 提交于
      After making dirty a 100M file, the normal behavior is to start the
      writeback for all data after 30s delays.  But sometimes the following
      happens instead:
      
      	- after 30s:    ~4M
      	- after 5s:     ~4M
      	- after 5s:     all remaining 92M
      
      Some analyze shows that the internal io dispatch queues goes like this:
      
      		s_io            s_more_io
      		-------------------------
      	1)	100M,1K         0
      	2)	1K              96M
      	3)	0               96M
      1) initial state with a 100M file and a 1K file
      
      2) 4M written, nr_to_write <= 0, so write more
      
      3) 1K written, nr_to_write > 0, no more writes(BUG)
      
      nr_to_write > 0 in (3) fools the upper layer to think that data have all
      been written out.  The big dirty file is actually still sitting in
      s_more_io.  We cannot simply splice s_more_io back to s_io as soon as s_io
      becomes empty, and let the loop in generic_sync_sb_inodes() continue: this
      may starve newly expired inodes in s_dirty.  It is also not an option to
      draw inodes from both s_more_io and s_dirty, an let the loop go on: this
      might lead to live locks, and might also starve other superblocks in sync
      time(well kupdate may still starve some superblocks, that's another bug).
      
      We have to return when a full scan of s_io completes.  So nr_to_write > 0
      does not necessarily mean that "all data are written".  This patch
      introduces a flag writeback_control.more_io to indicate that more io should
      be done.  With it the big dirty file no longer has to wait for the next
      kupdate invokation 5s later.
      
      In sync_sb_inodes() we only set more_io on super_blocks we actually
      visited.  This avoids the interaction between two pdflush deamons.
      
      Also in __sync_single_inode() we don't blindly keep requeuing the io if the
      filesystem cannot progress.  Failing to do so may lead to 100% iowait.
      Tested-by: NMike Snitzer <snitzer@gmail.com>
      Signed-off-by: NFengguang Wu <wfg@mail.ustc.edu.cn>
      Cc: Michael Rubin <mrubin@google.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      8bc3be27
    • S
      mm: fix section mismatch warning in sparse.c · a322f8ab
      Sam Ravnborg 提交于
      Fix following warning:
      WARNING: mm/built-in.o(.text+0x22069): Section mismatch in reference from the function sparse_early_usemap_alloc() to the function .init.text:__alloc_bootmem_node()
      
      static sparse_early_usemap_alloc() were used only by sparse_init()
      and with sparse_init() annotated _init it is safe to
      annotate sparse_early_usemap_alloc with __init too.
      Signed-off-by: NSam Ravnborg <sam@ravnborg.org>
      Cc: Andy Whitcroft <apw@shadowen.org>
      Cc: Mel Gorman <mel@csn.ul.ie>
      Cc: Christoph Lameter <clameter@sgi.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      a322f8ab
    • N
      mm: fix PageUptodate data race · 0ed361de
      Nick Piggin 提交于
      After running SetPageUptodate, preceeding stores to the page contents to
      actually bring it uptodate may not be ordered with the store to set the
      page uptodate.
      
      Therefore, another CPU which checks PageUptodate is true, then reads the
      page contents can get stale data.
      
      Fix this by having an smp_wmb before SetPageUptodate, and smp_rmb after
      PageUptodate.
      
      Many places that test PageUptodate, do so with the page locked, and this
      would be enough to ensure memory ordering in those places if
      SetPageUptodate were only called while the page is locked.  Unfortunately
      that is not always the case for some filesystems, but it could be an idea
      for the future.
      
      Also bring the handling of anonymous page uptodateness in line with that of
      file backed page management, by marking anon pages as uptodate when they
      _are_ uptodate, rather than when our implementation requires that they be
      marked as such.  Doing allows us to get rid of the smp_wmb's in the page
      copying functions, which were especially added for anonymous pages for an
      analogous memory ordering problem.  Both file and anonymous pages are
      handled with the same barriers.
      
      FAQ:
      Q. Why not do this in flush_dcache_page?
      A. Firstly, flush_dcache_page handles only one side (the smb side) of the
      ordering protocol; we'd still need smp_rmb somewhere. Secondly, hiding away
      memory barriers in a completely unrelated function is nasty; at least in the
      PageUptodate macros, they are located together with (half) the operations
      involved in the ordering. Thirdly, the smp_wmb is only required when first
      bringing the page uptodate, wheras flush_dcache_page should be called each time
      it is written to through the kernel mapping. It is logically the wrong place to
      put it.
      
      Q. Why does this increase my text size / reduce my performance / etc.
      A. Because it is adding the necessary instructions to eliminate the data-race.
      
      Q. Can it be improved?
      A. Yes, eg. if you were to create a rule that all SetPageUptodate operations
      run under the page lock, we could avoid the smp_rmb places where PageUptodate
      is queried under the page lock. Requires audit of all filesystems and at least
      some would need reworking. That's great you're interested, I'm eagerly awaiting
      your patches.
      Signed-off-by: NNick Piggin <npiggin@suse.de>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      0ed361de
    • S
      page migraton: handle orphaned pages · 62e1c553
      Shaohua Li 提交于
      Orphaned page might have fs-private metadata, the page is truncated.  As
      the page hasn't mapping, page migration refuse to migrate the page.  It
      appears the page is only freed in page reclaim and if zone watermark is
      low, the page is never freed, as a result migration always fail.  I thought
      we could free the metadata so such page can be freed in migration and make
      migration more reliable.
      
      [akpm@linux-foundation.org: go direct to try_to_free_buffers()]
      Signed-off-by: NShaohua Li <shaohua.li@intel.com>
      Acked-by: NNick Piggin <npiggin@suse.de>
      Acked-by: NChristoph Lameter <clameter@sgi.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      62e1c553
    • Y
      Document lowmem_reserve_ratio · 7786fa9a
      Yasunori Goto 提交于
      Though the lower_zone_protection was changed to lowmem_reserve_ratio, the
      document has been not changed.  The lowmem_reserve_ratio seems quite hard
      to estimate, but there is no guidance.  This patch is to change document
      for it.
      Signed-off-by: NYasunori Goto <y-goto@jp.fujitsu.com>
      Cc: Andrea Arcangeli <andrea@cpushare.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      7786fa9a
    • M
      check ADVICE of fadvise64_64 even if get_xip_page is given · b5beb1ca
      Masatake YAMATO 提交于
      I've written some test programs in ltp project.  During writing I met an
      problem which I cannot solve in user land.  So I wrote a patch for linux
      kernel.  Please, include this patch if acceptable.
      
      The test program tests the 4th parameter of fadvise64_64:
      
          long sys_fadvise64_64(int fd, loff_t offset, loff_t len, int advice);
      
      My test case calls fadvise64_64 with invalid advice value and checks errno is
      set to EINVAL.  About the advice parameter man page says:
      
          ...
          Permissible values for advice include:
      
      	   POSIX_FADV_NORMAL
                        ...
      	   POSIX_FADV_SEQUENTIAL
                        ...
      	   POSIX_FADV_RANDOM
      		  ...
      	   POSIX_FADV_NOREUSE
                        ...
      	   POSIX_FADV_WILLNEED
                        ...
      	   POSIX_FADV_DONTNEED
      		  ...
          ERRORS
                 ...
      	   EINVAL An invalid value was specified for advice.
      
      However, I got a bug report that the system call invocations
      in my test case returned 0 unexpectedly.
      
      I've inspected the kernel code:
      
          asmlinkage long sys_fadvise64_64(int fd, loff_t offset, loff_t len, int advice)
          {
      	    struct file *file = fget(fd);
      	    struct address_space *mapping;
      	    struct backing_dev_info *bdi;
      	    loff_t endbyte;			/* inclusive */
      	    pgoff_t start_index;
      	    pgoff_t end_index;
      	    unsigned long nrpages;
      	    int ret = 0;
      
      	    if (!file)
      		    return -EBADF;
      
      	    if (S_ISFIFO(file->f_path.dentry->d_inode->i_mode)) {
      		    ret = -ESPIPE;
      		    goto out;
      	    }
      
      	    mapping = file->f_mapping;
      	    if (!mapping || len < 0) {
      		    ret = -EINVAL;
      		    goto out;
      	    }
      
      	    if (mapping->a_ops->get_xip_page)
      		    /* no bad return value, but ignore advice */
      		    goto out;
          ...
          out:
      	    fput(file);
      	    return ret;
          }
      
      I found the advice parameter is just ignored in the case
      mapping->a_ops->get_xip_page is given. This behavior is different from
      what is written on the man page. Is this o.k.?
      
      get_xip_page is given if CONFIG_EXT2_FS_XIP is true.
      Anyway I cannot find the easy way to detect get_xip_page
      field is given or CONFIG_EXT2_FS_XIP is true from the
      user space.
      
      I propose the following patch which checks the advice parameter
      even if get_xip_page is given.
      Signed-off-by: NMasatake YAMATO <yamato@redhat.com>
      Acked-by: NCarsten Otte <cotte@de.ibm.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      b5beb1ca
    • L
      Include count of pagecache pages in show_mem() output · e6f3602d
      Larry Woodman 提交于
      The show_mem() output does not include the total number of pagecache
      pages.  This would be helpful when analyzing the debug information in
      the /var/log/messages file after OOM kills occur.
      
      This patch includes the total pagecache pages in that output.
      Signed-off-by: NLarry Woodman <lwoodman@redhat.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      e6f3602d
    • B
      Fix dirty page accounting leak with ext3 data=journal · a2b34564
      Bjorn Steinbrink 提交于
      In 46d2277c ("Clean up and make
      try_to_free_buffers() not race with dirty pages"), try_to_free_buffers
      was changed to bail out if the page was dirty.
      
      That in turn caused truncate_complete_page to leak massive amounts of
      memory, because the dirty bit was only cleared after the call to
      try_to_free_buffers.
      
      So the call to cancel_dirty_page was moved up to have the dirty bit
      cleared early in 3e67c098 ("truncate:
      clear page dirtiness before running try_to_free_buffers()").
      
      The problem with that fix is, that the page can be redirtied after
      cancel_dirty_page was called, eg. like this:
      
      truncate_complete_page()
        cancel_dirty_page() // PG_dirty cleared, decr. dirty pages
        do_invalidatepage()
          ext3_invalidatepage()
            journal_invalidatepage()
              journal_unmap_buffer()
                __dispose_buffer()
                  __journal_unfile_buffer()
                    __journal_temp_unlink_buffer()
                      mark_buffer_dirty(); // PG_dirty set, incr. dirty pages
      
      And then we end up with dirty pages being wrongly accounted.
      
      As a result, in ecdfc978 ("Resurrect
      'try_to_free_buffers()' VM hackery") the changes to try_to_free_buffers
      were reverted, so the original reason for the massive memory leak is
      gone, and we can also revert the move of the call to cancel_dirty_page
      from truncate_complete_page and get the accounting right again.
      
      I'm not sure if it matters, but opposed to the final check in
      __remove_from_page_cache, this one also cares about the task io
      accounting, so maybe we want to use this instead, although it's not
      quite the clean fix either.
      Signed-off-by: NBjörn Steinbrink <B.Steinbrink@gmx.de>
      Tested-by: NKrzysztof Piotr Oledzki <ole@ans.pl>
      Cc: Jan Kara <jack@ucw.cz>
      Cc: Nick Piggin <nickpiggin@yahoo.com.au>
      Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
      Cc: Thomas Osterried <osterried@jesse.de>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      a2b34564
    • Q
      set_page_refcounted() VM_BUG_ON fix · ae1276b9
      Qi Yong 提交于
      The current PageTail semantic is that a PageTail page is first a
      PageCompound page.  So remove the redundant PageCompound test in
      set_page_refcounted().
      Signed-off-by: NQi Yong <qiyong@fc-cn.com>
      Cc: Christoph Lameter <clameter@sgi.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      ae1276b9
    • H
      mm: remove fastcall from mm/ · 920c7a5d
      Harvey Harrison 提交于
      fastcall is always defined to be empty, remove it
      
      [akpm@linux-foundation.org: coding-style fixes]
      Signed-off-by: NHarvey Harrison <harvey.harrison@gmail.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      920c7a5d