1. 22 May, 2004 40 commits
    • Andrew Morton's avatar
      [PATCH] Convert i_shared_sem back to a spinlock · c0868962
      Andrew Morton authored
      Having a semaphore in there causes modest performance regressions on heavily
      mmap-intensive workloads on some hardware.  Specifically, up to 30% in SDET on
      NUMAQ and big PPC64.
      
      So switch it back to being a spinlock.  This does mean that unmap_vmas() needs
      to be told whether or not it is allowed to schedule away; that's simple to do
      via the zap_details structure.
      
      This change means that there will be high scheuling latencies when someone
      truncates a large file which is currently mmapped, but nobody does that
      anyway.  The scheduling points in unmap_vmas() are mainly for munmap() and
      exit(), and they still will work OK for that.
      
      From: Hugh Dickins <hugh@veritas.com>
      
        Sorry, my premature optimizations (trying to pass down NULL zap_details
        except when needed) have caught you out doubly: unmap_mapping_range_list was
        NULLing the details even though atomic was set; and if it hadn't, then
        zap_pte_range would have missed free_swap_and_cache and pte_clear when pte
        not present.  Moved the optimization into zap_pte_range itself.  Plus
        massive documentation update.
      
      From: Hugh Dickins <hugh@veritas.com>
      
        Here's a second patch to add to the first: mremap's cows can't come home
        without releasing the i_mmap_lock, better move the whole "Subtle point"
        locking from move_vma into move_page_tables.  And it's possible for the file
        that was behind an anonymous page to be truncated while we drop that lock,
        don't want to abort mremap because of VM_FAULT_SIGBUS.
      
        (Eek, should we be checking do_swap_page of a vm_file area against the
        truncate_count sequence?  Technically yes, but I doubt we need bother.)
      
      
      - We cannot hold i_mmap_lock across move_one_page() because
        move_one_page() needs to perform __GFP_WAIT allocations of pagetable pages.
      
      - Move the cond_resched() out so we test it once per page rather than only
        when move_one_page() returns -EAGAIN.
      c0868962
    • Andrew Morton's avatar
      [PATCH] rmap 13 include/asm deletions · 71a18745
      Andrew Morton authored
      From: Hugh Dickins <hugh@veritas.com>
      
      Delete include/asm*/rmap.h
      Delete pte_addr_t typedef from include/asm*/pgtable.h
      Delete KM_PTE2 from subset of include/asm*/kmap_types.h
      Beware when 4G/4G returns to -mm: i386 may need KM_FILLER for 8K stack.
      71a18745
    • Andrew Morton's avatar
      [PATCH] rmap 12 pgtable remove rmap · 865fadf0
      Andrew Morton authored
      From: Hugh Dickins <hugh@veritas.com>
      
      Remove the support for pte_chain rmap from page table initialization, just
      continue to maintain nr_page_table_pages (but only for user page tables -
      it also counted vmalloc page tables before, little need, and I'm unsure if
      per-cpu stats are safe early enough on all arches).  mm/memory.c is the
      only core file affected.
      
      But ppc and ppc64 have found the old rmap page table initialization useful
      to support their ptep_test_and_clear_young: so transfer rmap's
      initialization to them (even on kernel page tables?  well, okay).
      865fadf0
    • Andrew Morton's avatar
      [PATCH] rmap 11 mremap moves · 70b671f8
      Andrew Morton authored
      From: Hugh Dickins <hugh@veritas.com>
      
      A weakness of the anonmm scheme is its difficulty in tracking pages shared
      between two or more mms (one being an ancestor of the other), when mremap has
      been used to move a range of pages in one of those mms.  mremap move is not
      very common anyway, and it's more often used on a page range exclusive to the
      mm; but uncommon though it may be, we must not allow unlocked pages to become
      unswappable.
      
      This patch follows Linus' suggestion, simply to take a private copy of the
      page in such a case: early C-O-W.  My previous implementation was daft with
      respect to pages currently on swap: it insisted on swapping them in to copy
      them.  No need for that: just take the copy when a page is brought in from
      swap, and its intended address is found to clash with what rmap has already
      noted.
      
      If do_swap_page has to make this copy in the mremap moved case (simply a call
      to do_wp_page), might as well do so also in the case when it's a write access
      but the page not exclusive, it's always seemed a little odd that swapin needed
      a second fault for that.  A bug even: get_user_pages force imagines that a
      single call to handle_mm_fault must break C-O-W.  Another bugfix: swapoff's
      unuse_process didn't check is_vm_hugetlb_page.
      
      Andrea's anon_vma has no such problem with mremap moved pages, handling them
      with elegant use of vm_pgoff - though at some cost to vma merging.  How
      important is it to handle them efficiently?  For now there's a msg
      printk(KERN_WARNING "%s: mremap moved %d cows\n", current->comm, cows);
      70b671f8
    • Andrew Morton's avatar
      [PATCH] rmap 10 add anonmm rmap · 6bccf794
      Andrew Morton authored
      From: Hugh Dickins <hugh@veritas.com>
      
      Hugh's anonmm object-based reverse mapping scheme for anonymous pages.  We
      have not yet decided whether to adopt this scheme, or Andrea's more advanced
      anon_vma scheme.  anonmm is easier for me to merge quickly, to replace the
      pte_chain rmap taken out in the previous patch; a patch to install Andrea's
      anon_vma will follow in due course.
      
      Why build up and tear down chains of pte pointers for anonymous pages, when a
      page can only appear at one particular address, in a restricted group of mms
      that might share it?  (Except: see next patch on mremap.)
      
      Introduce struct anonmm per mm to track anonymous pages, all forks from one
      exec sharing the same bundle of linked anonmms.  Anonymous pages originate in
      one mm, but may be forked into another mm of the bundle later on.  Callouts
      from fork.c to allocate, dup and exit the anonmm structure private to rmap.c.
      
      From: Hugh Dickins <hugh@veritas.com>
      
        Two concurrent exits (of the last two mms sharing the anonhd).  First
        exit_rmap brings anonhd->count down to 2, gets preempted (at the
        spin_unlock) by second, which brings anonhd->count down to 1, sees it's 1
        and frees the anonhd (without making any change to anonhd->count itself),
        cpu goes on to do something new which reallocates the old anonhd as a new
        struct anonmm (probably not a head, in which case count will start at 1),
        first resumes after the spin_unlock and sees anonhd->count 1, frees "anonhd"
        again, it's used for something else, a later exit_rmap list_del finds list
        corrupt.
      6bccf794
    • Andrew Morton's avatar
      [PATCH] rmap 9 remove pte_chains · 123e4df7
      Andrew Morton authored
      From: Hugh Dickins <hugh@veritas.com>
      
      Lots of deletions: the next patch will put in the new anon rmap, which
      should look clearer if first we remove all of the old pte-pointer-based
      rmap from the core in this patch - which therefore leaves anonymous rmap
      totally disabled, anon pages locked in memory until process frees them.
      
      Leave arch files (and page table rmap) untouched for now, clean them up in
      a later batch.  A few constructive changes amidst all the deletions:
      
      Choose names (e.g.  page_add_anon_rmap) and args (e.g.  no more pteps) now
      so we need not revisit so many files in the next patch.  Inline function
      page_dup_rmap for fork's copy_page_range, simply bumps mapcount under lock.
       cond_resched_lock in copy_page_range.  Struct page rearranged: no pte
      union, just mapcount moved next to atomic count, so two ints can occupy one
      long on 64-bit; i386 struct page now 32 bytes even with PAE.  Never pass
      PageReserved to page_remove_rmap, only do_wp_page did so.
      
      
      From: Hugh Dickins <hugh@veritas.com>
      
        Move page_add_anon_rmap's BUG_ON(page_mapping(page)) inside the rmap_lock
        (well, might as well just check mapping if !mapcount then): if this page is
        being mapped or unmapped on another cpu at the same time, page_mapping's
        PageAnon(page) and page->mapping are volatile.
      
        But page_mapping(page) is used more widely: I've a nasty feeling that
        clear_page_anon, page_add_anon_rmap and/or page_mapping need barriers added
        (also in 2.6.6 itself),
      123e4df7
    • Andrew Morton's avatar
      [PATCH] slab: consolidate panic code · b33a7bad
      Andrew Morton authored
      Many places do:
      
      	if (kmem_cache_create(...) == NULL)
      		panic(...);
      
      We can consolidate all that by passing another flag to kmem_cache_create()
      which says "panic if it doesn't work".
      b33a7bad
    • Andrew Morton's avatar
      [PATCH] rmap 8 unmap nonlinear · 108e3158
      Andrew Morton authored
      From: Hugh Dickins <hugh@veritas.com>
      
      The previous patch let the ptes of file pages be located via page
      ->mapping->i_mmap and i_mmap_shared lists of vmas; which works well unless
      the vma is VM_NONLINEAR - one in which sys_remap_file_pages has been used
      to place pages in unexpected places, to avoid an explosion of distinct
      unmergable vmas.  Such pages were effectively locked in memory.
      
      page_referenced_file is already skipping nonlinear vmas, they'd just waste
      its time, and age unfairly any pages in their proper positions.  Now extend
      try_to_unmap_file, to persuade it to swap from nonlinears.
      
      Ignoring the page requested, try to unmap cluster of 32 neighbouring ptes
      (in worst case all empty slots) in a nonlinear vma, then move on to the
      next vma; stopping when we've unmapped at least as many maps as the
      requested page had (vague guide of how hard to try), or have reached the
      end.  With large sparse nonlinear vmas, this could take a long time:
      inserted a cond_resched while no locks are held, unusual at this level but
      I think okay, shrink_list does so.
      
      Use vm_private_data a little like the old mm->swap_address, as a cursor
      recording how far we got, so we don't attack the same ptes next time around
      (earlier tried inserting an empty marker vma in the list, but that got
      messy).  How well this will work on real- life nonlinear vmas remains to be
      seen, but should work better than locking them all in memory, or swapping
      everything out all the time.
      
      Existing users of vm_private_data have either VM_RESERVED or VM_DONTEXPAND
      set, both of which are in the VM_SPECIAL category where we never try to
      merge vmas: so removed the vm_private_data test from is_mergeable_vma, so
      we can still merge VM_NONLINEARs.  Of course, we could instead add another
      field to vm_area_struct.
      108e3158
    • Andrew Morton's avatar
      [PATCH] rmap 7 object-based rmap · cab971db
      Andrew Morton authored
      From: Hugh Dickins <hugh@veritas.com>
      
      Dave McCracken's object-based reverse mapping scheme for file pages: why
      build up and tear down chains of pte pointers for file pages, when
      page->mapping has i_mmap and i_mmap_shared lists of all the vmas which
      might contain that page, and it appears at one deterministic position
      within the vma (unless vma is nonlinear - see next patch)?
      
      Has some drawbacks: more work to locate the ptes from page_referenced and
      try_to_unmap, especially if the i_mmap lists contain a lot of vmas covering
      different ranges; has to down_trylock the i_shared_sem, and hope that
      doesn't fail too often.  But attractive in that it uses less lowmem, and
      shifts the rmap burden away from the hot paths, to swapout.
      
      Hybrid scheme for the moment: carry on with pte_chains for anonymous pages,
      that's unchanged; but file pages keep mapcount in the pte union of struct
      page, where anonymous pages keep chain pointer or direct pte address: so
      page_mapped(page) works on both.
      
      Hugh massaged it a little: distinct page_add_file_rmap entry point; list
      searches check rss so as not to waste time on mms fully swapped out; check
      mapcount to terminate once all ptes have been found; and a WARN_ON if
      page_referenced should have but couldn't find all the ptes.
      cab971db
    • Andrew Morton's avatar
      [PATCH] __set_page_dirty_nobuffers race fix · d61ae266
      Andrew Morton authored
      Running __mark_inode_dirty() against a swapcache page is illegal and will
      oops.
      
      I see a race in set_page_dirty() wherein it can be called with a PageSwapCache
      page, but if the page is removed from swapcache after
      __set_page_dirty_nobuffers() drops tree_lock(), we have the situation where
      PageSwapCache() is false, but local variable `mapping' points at swapcache.
      
      Handle that by checking for non-null mapping->host.  We don't care about the
      page state at this point - we're only interested in the inode.
      
      
      
      There is a converse case: what if a page is added to swapcache as we are
      running set_page_dirty() against it?
      
      In this case the page gets its PG_dirty flag set but it is not tagged as dirty
      in the swapper_space radix tree.  The swap writeout code will handle this OK
      and test_clear_page_dirty()'s call to
      radix_tree_tag_clear(PAGECACHE_TAG_DIRTY) will silently have no effect.  The
      only downside is that future radix-tree-based writearound won't notice that
      such pages are dirty and swap IO scheduling will be a teensy bit worse.
      
      
      The patch also fixes the (silly) testing of local variable `mapping' to see if
      the page was truncated.  We should test page_mapping() for that.
      d61ae266
    • Andrew Morton's avatar
      [PATCH] Make sync_page use swapper_space again · e6dfd92e
      Andrew Morton authored
      Revert recent changes to sync_page().  Now that page_mapping() returns
      &swapper_space for swapcache pages we don't need to test for PageSwapCache in
      sync_page().
      e6dfd92e
    • Andrew Morton's avatar
      [PATCH] vmscan: revert may_enter_fs changes · 8ea360d4
      Andrew Morton authored
      Fix up the "may we call writepage" logic for the swapcache changes.
      8ea360d4
    • Andrew Morton's avatar
      [PATCH] revert recent swapcache handling changes · e74193ad
      Andrew Morton authored
      Go back to the 2.6.5 concepts, with rmap additions.  In particular:
      
      - Implement Andrea's flavour of page_mapping().  This function opaquely does
        the right thing for pagecache pages, anon pages and for swapcache pages.
      
        The critical thing here is that page_mapping() returns &swapper_space for
        swapcache pages without actually requiring the storage at page->mapping. 
        This frees page->mapping for the anonmm/anonvma metadata.
      
      - Andrea and Hugh placed the pagecache index of swapcache pages into
        page->private rather than page->index.  So add new page_index() function
        which hides this.
      
      - Make swapper_space.set_page_dirty() again point at
        __set_page_dirty_buffers().  If we don't do that, a bare set_page_dirty()
        will fall through to __set_page_dirty_buffers(), which is silly.
      
        This way, __set_page_dirty_buffers() can continue to use page->mapping.
        It should never go near anon or swapcache pages.
      
      - Give swapper_space a ->set_page_dirty address_space_operation method, so
        that set_page_dirty() will not fall through to __set_page_dirty_buffers()
        for swapcache pages.  That function is not set up to handle them.
      
      
      The main effect of these changes is that swapcache pages are treated more
      similarly to pagecache pages.  And we are again tagging swapcache pages as
      dirty in their radix tree, which is a requirement if we later wish to
      implement swapcache writearound based on tagged radix-tree walks.
      e74193ad
    • Andrew Morton's avatar
      [PATCH] __add_to_swap_cache and add_to_pagecache() simplification · 7379e302
      Andrew Morton authored
      Simplify the logic in there a bit.
      7379e302
    • Andrew Morton's avatar
      [PATCH] Make swapper_space tree_lock irq-safe · b6c418dc
      Andrew Morton authored
      ->tree_lock is supposed to be IRQ-safe.  Hugh worked out that with his
      changes, we never actually take it from interrupt context, so spin_lock() is
      sufficient.
      
      Apart from kinda freaking me out, the analysis which led to this decision
      becomes untrue with later patches.  So make it irq-safe.
      b6c418dc
    • Linus Torvalds's avatar
      Merge bk://kernel.bkbits.net/davem/net-2.6 · a20a9dee
      Linus Torvalds authored
      into ppc970.osdl.org:/home/torvalds/v2.6/linux
      a20a9dee
    • Linus Torvalds's avatar
      Avoid type warning in comparison by making it explicit. · 4d4aaa67
      Linus Torvalds authored
      (The difference between two pointers is a "size_t", while
      MAX_LEN and the result here are "int"s).
      4d4aaa67
    • Stephen Hemminger's avatar
      [BRIDGE]: Forwarding table sanity checks. · 649f71c5
      Stephen Hemminger authored
      Forwarding table paranoia:
      * Solve some potential problems if a device changes address and one or
        more device has the same address.  
      * Warn if new device added to a bridge matches a entry that has shown
        up on the network.
      * Also don't put static entries in the timer list, they don't time
        out so shouldn't be there.
      649f71c5
    • Stephen Hemminger's avatar
      [BRIDGE]: Compat hooks for new-ioctl interface. · d6bd6619
      Stephen Hemminger authored
      Replacement 64 bit compatibility code for the new ioctl's.  The new 
      ioctl's all pass through clean, but for the old style ioctl's it uses
      the mis-feature of the earlier bridge-utils that they check the API version.
      
      So if an old 32bit version of brctl is run on a 64bit platform it will
      report
      	bridge utilities not compatible with kernel version
      
      Tested on Itanium 1; but should solve issue for sparc, ppc, and x86_64
      d6bd6619
    • Stephen Hemminger's avatar
      [BRIDGE]: New ioctl interface for 32/64 compatability. · 5075405c
      Stephen Hemminger authored
      Add four new ioctl's for the operations that can't be done through sysfs.
      The existing bridge ioctl's are multiplexed, and most go through SIOCDEVPRIVATE
      so they won't work in a mixed 32/64bit environment.
      
      The new release of bridge-utils will use these if possible, and fall
      back to the old interface.
      5075405c
    • Stephen Hemminger's avatar
      [BRIDGE]: Add sysfs support. · 3d702922
      Stephen Hemminger authored
      3d702922
    • Stephen Hemminger's avatar
      [BRIDGE]: Expose timer_residue function for use by sysfs. · f1d65789
      Stephen Hemminger authored
      Move the local function timer_residue to br_timer_value so it can
      be used by both ioctl and sysfs code.
      f1d65789
    • Stephen Hemminger's avatar
      [BRIDGE]: Read forwarding table chunk at a time. · 7e40dbf8
      Stephen Hemminger authored
      Change how the read of forwarding table works.  Instead of copying
      entries to user one at a time, use an intermediate kernel buffer and
      do up to a page at a chunk.
      
      This gets rid of some awkward code dealing with entries getting deleted
      during the copy.  And allows same function to be used by later sysfs
      hook.
      7e40dbf8
    • Stephen Hemminger's avatar
      [BRIDGE]: Fix deadlock on device removal. · 367c89b5
      Stephen Hemminger authored
      Fix a deadlock where deleting a device call br_del_if with lock held.
      br_del_if doesn't want to be called under lock anymore.
      367c89b5
    • Stephen Hemminger's avatar
      [BRIDGE]: Ioctl cleanup and consolidation. · 39b81cce
      Stephen Hemminger authored
      Merge the ioctl stub calls that just end up calling the sub-function
      to do the actual ioctl.  Move br_get_XXX_ifindices into the ioctl file
      as well where they can be static.
      39b81cce
    • Stephen Hemminger's avatar
      [BRIDGE]: Relax locking on add/delete. · af13a450
      Stephen Hemminger authored
      Relax the locking on add/delete interfaces to a bridge.  Since these operations
      are already called with RTNL semaphore, only need to hold the bridge lock while
      doing operations related to STP and processing path.  This is necessary for later
      sysfs support where those operations might sleep.
      af13a450
    • Stephen Hemminger's avatar
      [BRIDGE]: Cleanup of bridge allocation. · 20d50e8c
      Stephen Hemminger authored
      Minor cleanup (lead in to later sysfs support).  
      Change new_nb to new_bridge_dev and return the net_device rather than
      bridge because that is what the caller wants anyway.
      20d50e8c
    • Stephen Hemminger's avatar
      [BRIDGE]: Handle delete of multiple devices with same address. · c5c0a0e3
      Stephen Hemminger authored
      This fixes the issue discovered when removing bluetooth devices from a bridge.
      Need to add special case code when forwarding table is being cleaned up to 
      handle the case where several devices share the same hardware address.
      c5c0a0e3
    • Herbert Xu's avatar
      [IPSEC]: Lock policy in policy timer. · e8d12276
      Herbert Xu authored
      e8d12276
    • Bartlomiej Zolnierkiewicz's avatar
      [PATCH] IDE PCI: don't initialize fields of static chipset tables to zero · 46f55c63
      Bartlomiej Zolnierkiewicz authored
      Also remove unused EOL define from ide.h.
      
      This trivial patch makes grepping a lot easier.
      46f55c63
    • Bartlomiej Zolnierkiewicz's avatar
      [PATCH] two fixups for my ARM/ARM26 IDE changes · 58148fac
      Bartlomiej Zolnierkiewicz authored
      - initializing needs to be set to 1 before calling ide_arm_init()
      
      - ide_default_io_ctl() should be 0 on arm26
      58148fac
    • Bartlomiej Zolnierkiewicz's avatar
      [PATCH] remove dead drivers/ide/ppc/swarm.c · cbc6f01b
      Bartlomiej Zolnierkiewicz authored
      This driver was partially merged in 2.5.32 and never compiled in 2.5/2.6.
      It was fixed in linux-mips CVS but has been broken again about 5 months ago.
      Just remove it for now (it is in wrong directory anyway).
      cbc6f01b
    • Adrian Bunk's avatar
      [PATCH] more comx removal · 6f9af6fc
      Adrian Bunk authored
      The patch below removes the MAINTAINERS entry for the removed comx
      driver.
      
      Additionally, the following comx header files could be removed:
        drivers/net/wan/mixcom.h
        drivers/net/wan/hscx.h
        drivers/net/wan/munich32x.h
        drivers/net/wan/falc-lh.h
      
      I've double-checked that none of them are used by any other driver.
      6f9af6fc
    • Adrian Bunk's avatar
      [PATCH] JFFS2_FS_NAND=y compile error · 8fcb7c33
      Adrian Bunk authored
      The case of CONFIG_JFFS2_FS_NAND=y got broken recently.
      
      The bug is obvious, and the fix is trivial:
      8fcb7c33
    • Andrew Morton's avatar
      [PATCH] autofs4: MAINTAINERS update · c56f34ad
      Andrew Morton authored
      From: Ian Kent <raven@themaw.net>
      
      This changes the autofs4 maintainer to me.  Recommended by Joe Perches and
      OKed with Jeremy.
      c56f34ad
    • Andrew Morton's avatar
      [PATCH] autofs4: printk cleanup · 2d9a3b29
      Andrew Morton authored
      From: Ian Kent <raven@themaw.net>
      
      This is a patch contributed by Joe Perches to automatically include the
      function name in the dprintk statements.
      2d9a3b29
    • Andrew Morton's avatar
      [PATCH] x86 cpuid cache info update · a7250728
      Andrew Morton authored
      From: Francois Romieu <romieu@fr.zoreil.com>
      
      Missing cache size format for Intel P4E (p.26 of doc.  241618-025, "Intel
      Processor Identification and the CPUID Instruction").
      a7250728
    • Andrew Morton's avatar
      [PATCH] i4l: Eicon driver: fix __devexit in prototype · dfbbadeb
      Andrew Morton authored
      From: Armin Schindler <armin@melware.de>
      
      Fixes a compiler warning about unused Eicon ISDN driver function if hotplug is
      disabled.
      dfbbadeb
    • Andrew Morton's avatar
      [PATCH] swsusp: fix devfs breakage introduced in 2.6.6 · 12186dc4
      Andrew Morton authored
      From: Pavel Machek <pavel@ucw.cz>
      
      This fixes bad interaction between devfs and swsusp.
      
      Check whether the swap device is the specified resume device, irrespective of
      whether they are specified by identical names.
      
      (Thus, device inode aliasing is allowed.  You can say /dev/hda4 instead of
      /dev/ide/host0/bus0/target0/lun0/part4 [if using devfs] and they'll be
      considered the same device.  This is *necessary* for devfs, since the resume
      code can only recognize the form /dev/hda4, but the suspend code would like
      the long name [as shown in 'cat /proc/mounts'].)
      
      [Thanks to devfs hero whose name I forgot.]
      12186dc4
    • Andrew Morton's avatar
      [PATCH] swsusp: kill unneccessary debugging · a7f8c55f
      Andrew Morton authored
      From: Pavel Machek <pavel@ucw.cz>
      
      This is no longer neccessary.  We have enough pauses elsewhere, and it works
      well enough that this is not needed.
      a7f8c55f