12 Feb, 2019

1 commit

  • One of the more common cases of allocation size calculations is finding
    the size of a structure that has a zero-sized array at the end, along
    with memory for some number of elements for that array. For example:

    struct foo {
    int stuff;
    void *entry[];
    };

    size = sizeof(struct foo) + count * sizeof(void *);
    instance = alloc(size, GFP_KERNEL)

    Instead of leaving these open-coded and prone to type mistakes, we can
    now use the new struct_size() helper:

    size = struct_size(instance, entry, count);
    instance = alloc(size, GFP_KERNEL)

    Notice that, in this case, variable sz is not necessary, hence it is
    removed.

    This code was detected with the help of Coccinelle.

    Signed-off-by: Gustavo A. R. Silva
    Signed-off-by: Pablo Neira Ayuso

    Gustavo A. R. Silva
     

28 Jun, 2018

1 commit

  • Netfilter assumes that if the socket is present in the skb, then
    it can be used because that reference is cleaned up while the skb
    is crossing netns.

    We want to change that to preserve the socket reference in a future
    patch, so this is a preparation updating netfilter to check if the
    socket netns matches before use it.

    Signed-off-by: Flavio Leitner
    Acked-by: Florian Westphal
    Signed-off-by: David S. Miller

    Flavio Leitner
     

07 Jun, 2018

1 commit

  • One of the more common cases of allocation size calculations is finding
    the size of a structure that has a zero-sized array at the end, along
    with memory for some number of elements for that array. For example:

    struct foo {
    int stuff;
    void *entry[];
    };

    instance = kmalloc(sizeof(struct foo) + sizeof(void *) * count, GFP_KERNEL);

    Instead of leaving these open-coded and prone to type mistakes, we can
    now use the new struct_size() helper:

    instance = kmalloc(struct_size(instance, entry, count), GFP_KERNEL);

    This patch makes the changes for kmalloc()-family (and kvmalloc()-family)
    uses. It was done via automatic conversion with manual review for the
    "CHECKME" non-standard cases noted below, using the following Coccinelle
    script:

    // pkey_cache = kmalloc(sizeof *pkey_cache + tprops->pkey_tbl_len *
    // sizeof *pkey_cache->table, GFP_KERNEL);
    @@
    identifier alloc =~ "kmalloc|kzalloc|kvmalloc|kvzalloc";
    expression GFP;
    identifier VAR, ELEMENT;
    expression COUNT;
    @@

    - alloc(sizeof(*VAR) + COUNT * sizeof(*VAR->ELEMENT), GFP)
    + alloc(struct_size(VAR, ELEMENT, COUNT), GFP)

    // mr = kzalloc(sizeof(*mr) + m * sizeof(mr->map[0]), GFP_KERNEL);
    @@
    identifier alloc =~ "kmalloc|kzalloc|kvmalloc|kvzalloc";
    expression GFP;
    identifier VAR, ELEMENT;
    expression COUNT;
    @@

    - alloc(sizeof(*VAR) + COUNT * sizeof(VAR->ELEMENT[0]), GFP)
    + alloc(struct_size(VAR, ELEMENT, COUNT), GFP)

    // Same pattern, but can't trivially locate the trailing element name,
    // or variable name.
    @@
    identifier alloc =~ "kmalloc|kzalloc|kvmalloc|kvzalloc";
    expression GFP;
    expression SOMETHING, COUNT, ELEMENT;
    @@

    - alloc(sizeof(SOMETHING) + COUNT * sizeof(ELEMENT), GFP)
    + alloc(CHECKME_struct_size(&SOMETHING, ELEMENT, COUNT), GFP)

    Signed-off-by: Kees Cook

    Kees Cook
     

28 Mar, 2018

1 commit


27 Mar, 2018

1 commit

  • Prefer the direct use of octal for permissions.

    Done with checkpatch -f --types=SYMBOLIC_PERMS --fix-inplace
    and some typing.

    Miscellanea:

    o Whitespace neatening around these conversions.

    Signed-off-by: Joe Perches
    Signed-off-by: David S. Miller

    Joe Perches
     

23 Mar, 2018

1 commit

  • Fun set of conflict resolutions here...

    For the mac80211 stuff, these were fortunately just parallel
    adds. Trivially resolved.

    In drivers/net/phy/phy.c we had a bug fix in 'net' that moved the
    function phy_disable_interrupts() earlier in the file, whilst in
    'net-next' the phy_error() call from this function was removed.

    In net/ipv4/xfrm4_policy.c, David Ahern's changes to remove the
    'rt_table_id' member of rtable collided with a bug fix in 'net' that
    added a new struct member "rt_mtu_locked" which needs to be copied
    over here.

    The mlxsw driver conflict consisted of net-next separating
    the span code and definitions into separate files, whilst
    a 'net' bug fix made some changes to that moved code.

    The mlx5 infiniband conflict resolution was quite non-trivial,
    the RDMA tree's merge commit was used as a guide here, and
    here are their notes:

    ====================

    Due to bug fixes found by the syzkaller bot and taken into the for-rc
    branch after development for the 4.17 merge window had already started
    being taken into the for-next branch, there were fairly non-trivial
    merge issues that would need to be resolved between the for-rc branch
    and the for-next branch. This merge resolves those conflicts and
    provides a unified base upon which ongoing development for 4.17 can
    be based.

    Conflicts:
    drivers/infiniband/hw/mlx5/main.c - Commit 42cea83f9524
    (IB/mlx5: Fix cleanup order on unload) added to for-rc and
    commit b5ca15ad7e61 (IB/mlx5: Add proper representors support)
    add as part of the devel cycle both needed to modify the
    init/de-init functions used by mlx5. To support the new
    representors, the new functions added by the cleanup patch
    needed to be made non-static, and the init/de-init list
    added by the representors patch needed to be modified to
    match the init/de-init list changes made by the cleanup
    patch.
    Updates:
    drivers/infiniband/hw/mlx5/mlx5_ib.h - Update function
    prototypes added by representors patch to reflect new function
    names as changed by cleanup patch
    drivers/infiniband/hw/mlx5/ib_rep.c - Update init/de-init
    stage list to match new order from cleanup patch
    ====================

    Signed-off-by: David S. Miller

    David S. Miller
     

12 Mar, 2018

1 commit

  • recent and hashlimit both create /proc files, but only check that
    name is 0 terminated.

    This can trigger WARN() from procfs when name is "" or "/".
    Add helper for this and then use it for both.

    Cc: Eric Dumazet
    Reported-by: Eric Dumazet
    Reported-by:
    Signed-off-by: Florian Westphal
    Signed-off-by: Pablo Neira Ayuso

    Florian Westphal
     

28 Feb, 2018

1 commit


15 Feb, 2018

1 commit


26 Jul, 2017

1 commit


09 May, 2017

1 commit

  • There are many code paths opencoding kvmalloc. Let's use the helper
    instead. The main difference to kvmalloc is that those users are
    usually not considering all the aspects of the memory allocator. E.g.
    allocation requests
    Reviewed-by: Boris Ostrovsky # Xen bits
    Acked-by: Kees Cook
    Acked-by: Vlastimil Babka
    Acked-by: Andreas Dilger # Lustre
    Acked-by: Christian Borntraeger # KVM/s390
    Acked-by: Dan Williams # nvdim
    Acked-by: David Sterba # btrfs
    Acked-by: Ilya Dryomov # Ceph
    Acked-by: Tariq Toukan # mlx4
    Acked-by: Leon Romanovsky # mlx5
    Cc: Martin Schwidefsky
    Cc: Heiko Carstens
    Cc: Herbert Xu
    Cc: Anton Vorontsov
    Cc: Colin Cross
    Cc: Tony Luck
    Cc: "Rafael J. Wysocki"
    Cc: Ben Skeggs
    Cc: Kent Overstreet
    Cc: Santosh Raspatur
    Cc: Hariprasad S
    Cc: Yishai Hadas
    Cc: Oleg Drokin
    Cc: "Yan, Zheng"
    Cc: Alexander Viro
    Cc: Alexei Starovoitov
    Cc: Eric Dumazet
    Cc: David Miller
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Michal Hocko
     

07 Apr, 2017

1 commit


18 Nov, 2016

1 commit

  • Make struct pernet_operations::id unsigned.

    There are 2 reasons to do so:

    1)
    This field is really an index into an zero based array and
    thus is unsigned entity. Using negative value is out-of-bound
    access by definition.

    2)
    On x86_64 unsigned 32-bit data which are mixed with pointers
    via array indexing or offsets added or subtracted to pointers
    are preffered to signed 32-bit data.

    "int" being used as an array index needs to be sign-extended
    to 64-bit before being used.

    void f(long *p, int i)
    {
    g(p[i]);
    }

    roughly translates to

    movsx rsi, esi
    mov rdi, [rsi+...]
    call g

    MOVSX is 3 byte instruction which isn't necessary if the variable is
    unsigned because x86_64 is zero extending by default.

    Now, there is net_generic() function which, you guessed it right, uses
    "int" as an array index:

    static inline void *net_generic(const struct net *net, int id)
    {
    ...
    ptr = ng->ptr[id - 1];
    ...
    }

    And this function is used a lot, so those sign extensions add up.

    Patch snipes ~1730 bytes on allyesconfig kernel (without all junk
    messing with code generation):

    add/remove: 0/0 grow/shrink: 70/598 up/down: 396/-2126 (-1730)

    Unfortunately some functions actually grow bigger.
    This is a semmingly random artefact of code generation with register
    allocator being used differently. gcc decides that some variable
    needs to live in new r8+ registers and every access now requires REX
    prefix. Or it is shifted into r12, so [r12+0] addressing mode has to be
    used which is longer than [r8]

    However, overall balance is in negative direction:

    add/remove: 0/0 grow/shrink: 70/598 up/down: 396/-2126 (-1730)
    function old new delta
    nfsd4_lock 3886 3959 +73
    tipc_link_build_proto_msg 1096 1140 +44
    mac80211_hwsim_new_radio 2776 2808 +32
    tipc_mon_rcv 1032 1058 +26
    svcauth_gss_legacy_init 1413 1429 +16
    tipc_bcbase_select_primary 379 392 +13
    nfsd4_exchange_id 1247 1260 +13
    nfsd4_setclientid_confirm 782 793 +11
    ...
    put_client_renew_locked 494 480 -14
    ip_set_sockfn_get 730 716 -14
    geneve_sock_add 829 813 -16
    nfsd4_sequence_done 721 703 -18
    nlmclnt_lookup_host 708 686 -22
    nfsd4_lockt 1085 1063 -22
    nfs_get_client 1077 1050 -27
    tcf_bpf_init 1106 1076 -30
    nfsd4_encode_fattr 5997 5930 -67
    Total: Before=154856051, After=154854321, chg -0.00%

    Signed-off-by: Alexey Dobriyan
    Signed-off-by: David S. Miller

    Alexey Dobriyan
     

03 Nov, 2016

1 commit


23 Sep, 2016

1 commit


19 Sep, 2015

1 commit


17 Feb, 2015

1 commit

  • given:
    -A INPUT -m recent --update --seconds 30 --hitcount 4
    and
    iptables-save > foo

    then
    iptables-restore < foo

    will fail with:
    kernel: xt_recent: hitcount (4) is larger than packets to be remembered (4) for table DEFAULT

    Even when the check is fixed, the restore won't work if the hitcount is
    increased to e.g. 6, since by the time checkentry runs it will find the
    'old' incarnation of the table.

    We can avoid this by increasing the maximum threshold silently; we only
    have to rm all the current entries of the table (these entries would
    not have enough room to handle the increased hitcount).

    This even makes (not-very-useful)
    -A INPUT -m recent --update --seconds 30 --hitcount 4
    -A INPUT -m recent --update --seconds 30 --hitcount 42
    work.

    Fixes: abc86d0f99242b7f142b (netfilter: xt_recent: relax ip_pkt_list_tot restrictions)
    Tracked-down-by: Chris Vine
    Signed-off-by: Florian Westphal
    Signed-off-by: Pablo Neira Ayuso

    Florian Westphal
     

27 Nov, 2014

1 commit

  • The maximum value for the hitcount parameter is given by
    "ip_pkt_list_tot" parameter (default: 20).

    Exceeding this value on the command line will cause the rule to be
    rejected. The parameter is also readonly, i.e. it cannot be changed
    without module unload or reboot.

    Store size per table, then base nstamps[] size on the hitcount instead.

    The module parameter is retained for backwards compatibility.

    Signed-off-by: Florian Westphal
    Signed-off-by: Pablo Neira Ayuso

    Florian Westphal
     

05 Jun, 2014

1 commit


02 May, 2013

1 commit

  • Supply accessor functions to set attributes in proc_dir_entry structs.

    The following are supplied: proc_set_size() and proc_set_user().

    Signed-off-by: David Howells
    Acked-by: Mauro Carvalho Chehab
    cc: linuxppc-dev@lists.ozlabs.org
    cc: linux-media@vger.kernel.org
    cc: netdev@vger.kernel.org
    cc: linux-wireless@vger.kernel.org
    cc: linux-pci@vger.kernel.org
    cc: netfilter-devel@vger.kernel.org
    cc: alsa-devel@alsa-project.org
    Signed-off-by: Al Viro

    David Howells
     

10 Apr, 2013

1 commit

  • The only part of proc_dir_entry the code outside of fs/proc
    really cares about is PDE(inode)->data. Provide a helper
    for that; static inline for now, eventually will be moved
    to fs/proc, along with the knowledge of struct proc_dir_entry
    layout.

    Signed-off-by: Al Viro

    Al Viro
     

27 Feb, 2013

1 commit

  • Pull vfs pile (part one) from Al Viro:
    "Assorted stuff - cleaning namei.c up a bit, fixing ->d_name/->d_parent
    locking violations, etc.

    The most visible changes here are death of FS_REVAL_DOT (replaced with
    "has ->d_weak_revalidate()") and a new helper getting from struct file
    to inode. Some bits of preparation to xattr method interface changes.

    Misc patches by various people sent this cycle *and* ocfs2 fixes from
    several cycles ago that should've been upstream right then.

    PS: the next vfs pile will be xattr stuff."

    * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (46 commits)
    saner proc_get_inode() calling conventions
    proc: avoid extra pde_put() in proc_fill_super()
    fs: change return values from -EACCES to -EPERM
    fs/exec.c: make bprm_mm_init() static
    ocfs2/dlm: use GFP_ATOMIC inside a spin_lock
    ocfs2: fix possible use-after-free with AIO
    ocfs2: Fix oops in ocfs2_fast_symlink_readpage() code path
    get_empty_filp()/alloc_file() leave both ->f_pos and ->f_version zero
    target: writev() on single-element vector is pointless
    export kernel_write(), convert open-coded instances
    fs: encode_fh: return FILEID_INVALID if invalid fid_type
    kill f_vfsmnt
    vfs: kill FS_REVAL_DOT by adding a d_weak_revalidate dentry op
    nfsd: handle vfs_getattr errors in acl protocol
    switch vfs_getattr() to struct path
    default SET_PERSONALITY() in linux/elf.h
    ceph: prepopulate inodes only when request is aborted
    d_hash_and_lookup(): export, switch open-coded instances
    9p: switch v9fs_set_create_acl() to inode+fid, do it before d_instantiate()
    9p: split dropping the acls from v9fs_set_create_acl()
    ...

    Linus Torvalds
     

23 Feb, 2013

1 commit


19 Feb, 2013

1 commit

  • proc_net_remove is only used to remove proc entries
    that under /proc/net,it's not a general function for
    removing proc entries of netns. if we want to remove
    some proc entries which under /proc/net/stat/, we still
    need to call remove_proc_entry.

    this patch use remove_proc_entry to replace proc_net_remove.
    we can remove proc_net_remove after this patch.

    Signed-off-by: Gao feng
    Signed-off-by: David S. Miller

    Gao feng
     

05 Jan, 2013

1 commit

  • xt_recent can try high order page allocations and this can fail.

    iptables: page allocation failure: order:9, mode:0xc0d0

    It also wastes about half the allocated space because of kmalloc()
    power-of-two roundups and struct recent_table layout.

    Use vmalloc() instead to save space and be less prone to allocation
    errors when memory is fragmented.

    Reported-by: Miroslav Kratochvil
    Reported-by: Dave Jones
    Reported-by: Harald Reindl
    Signed-off-by: Eric Dumazet
    Signed-off-by: Pablo Neira Ayuso

    Eric Dumazet
     

27 Dec, 2012

1 commit


15 Aug, 2012

1 commit


07 Jun, 2012

1 commit


16 Apr, 2012

1 commit


15 Oct, 2010

1 commit

  • All file_operations should get a .llseek operation so we can make
    nonseekable_open the default for future file operations without a
    .llseek pointer.

    The three cases that we can automatically detect are no_llseek, seq_lseek
    and default_llseek. For cases where we can we can automatically prove that
    the file offset is always ignored, we use noop_llseek, which maintains
    the current behavior of not returning an error from a seek.

    New drivers should normally not use noop_llseek but instead use no_llseek
    and call nonseekable_open at open time. Existing drivers can be converted
    to do the same when the maintainer knows for certain that no user code
    relies on calling seek on the device file.

    The generated code is often incorrectly indented and right now contains
    comments that clarify for each added line why a specific variant was
    chosen. In the version that gets submitted upstream, the comments will
    be gone and I will manually fix the indentation, because there does not
    seem to be a way to do that using coccinelle.

    Some amount of new code is currently sitting in linux-next that should get
    the same modifications, which I will do at the end of the merge window.

    Many thanks to Julia Lawall for helping me learn to write a semantic
    patch that does all this.

    ===== begin semantic patch =====
    // This adds an llseek= method to all file operations,
    // as a preparation for making no_llseek the default.
    //
    // The rules are
    // - use no_llseek explicitly if we do nonseekable_open
    // - use seq_lseek for sequential files
    // - use default_llseek if we know we access f_pos
    // - use noop_llseek if we know we don't access f_pos,
    // but we still want to allow users to call lseek
    //
    @ open1 exists @
    identifier nested_open;
    @@
    nested_open(...)
    {

    }

    @ open exists@
    identifier open_f;
    identifier i, f;
    identifier open1.nested_open;
    @@
    int open_f(struct inode *i, struct file *f)
    {

    }

    @ read disable optional_qualifier exists @
    identifier read_f;
    identifier f, p, s, off;
    type ssize_t, size_t, loff_t;
    expression E;
    identifier func;
    @@
    ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off)
    {

    }

    @ read_no_fpos disable optional_qualifier exists @
    identifier read_f;
    identifier f, p, s, off;
    type ssize_t, size_t, loff_t;
    @@
    ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off)
    {
    ... when != off
    }

    @ write @
    identifier write_f;
    identifier f, p, s, off;
    type ssize_t, size_t, loff_t;
    expression E;
    identifier func;
    @@
    ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off)
    {

    }

    @ write_no_fpos @
    identifier write_f;
    identifier f, p, s, off;
    type ssize_t, size_t, loff_t;
    @@
    ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off)
    {
    ... when != off
    }

    @ fops0 @
    identifier fops;
    @@
    struct file_operations fops = {
    ...
    };

    @ has_llseek depends on fops0 @
    identifier fops0.fops;
    identifier llseek_f;
    @@
    struct file_operations fops = {
    ...
    .llseek = llseek_f,
    ...
    };

    @ has_read depends on fops0 @
    identifier fops0.fops;
    identifier read_f;
    @@
    struct file_operations fops = {
    ...
    .read = read_f,
    ...
    };

    @ has_write depends on fops0 @
    identifier fops0.fops;
    identifier write_f;
    @@
    struct file_operations fops = {
    ...
    .write = write_f,
    ...
    };

    @ has_open depends on fops0 @
    identifier fops0.fops;
    identifier open_f;
    @@
    struct file_operations fops = {
    ...
    .open = open_f,
    ...
    };

    // use no_llseek if we call nonseekable_open
    ////////////////////////////////////////////
    @ nonseekable1 depends on !has_llseek && has_open @
    identifier fops0.fops;
    identifier nso ~= "nonseekable_open";
    @@
    struct file_operations fops = {
    ... .open = nso, ...
    +.llseek = no_llseek, /* nonseekable */
    };

    @ nonseekable2 depends on !has_llseek @
    identifier fops0.fops;
    identifier open.open_f;
    @@
    struct file_operations fops = {
    ... .open = open_f, ...
    +.llseek = no_llseek, /* open uses nonseekable */
    };

    // use seq_lseek for sequential files
    /////////////////////////////////////
    @ seq depends on !has_llseek @
    identifier fops0.fops;
    identifier sr ~= "seq_read";
    @@
    struct file_operations fops = {
    ... .read = sr, ...
    +.llseek = seq_lseek, /* we have seq_read */
    };

    // use default_llseek if there is a readdir
    ///////////////////////////////////////////
    @ fops1 depends on !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
    identifier fops0.fops;
    identifier readdir_e;
    @@
    // any other fop is used that changes pos
    struct file_operations fops = {
    ... .readdir = readdir_e, ...
    +.llseek = default_llseek, /* readdir is present */
    };

    // use default_llseek if at least one of read/write touches f_pos
    /////////////////////////////////////////////////////////////////
    @ fops2 depends on !fops1 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
    identifier fops0.fops;
    identifier read.read_f;
    @@
    // read fops use offset
    struct file_operations fops = {
    ... .read = read_f, ...
    +.llseek = default_llseek, /* read accesses f_pos */
    };

    @ fops3 depends on !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
    identifier fops0.fops;
    identifier write.write_f;
    @@
    // write fops use offset
    struct file_operations fops = {
    ... .write = write_f, ...
    + .llseek = default_llseek, /* write accesses f_pos */
    };

    // Use noop_llseek if neither read nor write accesses f_pos
    ///////////////////////////////////////////////////////////

    @ fops4 depends on !fops1 && !fops2 && !fops3 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
    identifier fops0.fops;
    identifier read_no_fpos.read_f;
    identifier write_no_fpos.write_f;
    @@
    // write fops use offset
    struct file_operations fops = {
    ...
    .write = write_f,
    .read = read_f,
    ...
    +.llseek = noop_llseek, /* read and write both use no f_pos */
    };

    @ depends on has_write && !has_read && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
    identifier fops0.fops;
    identifier write_no_fpos.write_f;
    @@
    struct file_operations fops = {
    ... .write = write_f, ...
    +.llseek = noop_llseek, /* write uses no f_pos */
    };

    @ depends on has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
    identifier fops0.fops;
    identifier read_no_fpos.read_f;
    @@
    struct file_operations fops = {
    ... .read = read_f, ...
    +.llseek = noop_llseek, /* read uses no f_pos */
    };

    @ depends on !has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
    identifier fops0.fops;
    @@
    struct file_operations fops = {
    ...
    +.llseek = noop_llseek, /* no read or write fn */
    };
    ===== End semantic patch =====

    Signed-off-by: Arnd Bergmann
    Cc: Julia Lawall
    Cc: Christoph Hellwig

    Arnd Bergmann
     

12 May, 2010

3 commits


20 Apr, 2010

1 commit


30 Mar, 2010

1 commit

  • …it slab.h inclusion from percpu.h

    percpu.h is included by sched.h and module.h and thus ends up being
    included when building most .c files. percpu.h includes slab.h which
    in turn includes gfp.h making everything defined by the two files
    universally available and complicating inclusion dependencies.

    percpu.h -> slab.h dependency is about to be removed. Prepare for
    this change by updating users of gfp and slab facilities include those
    headers directly instead of assuming availability. As this conversion
    needs to touch large number of source files, the following script is
    used as the basis of conversion.

    http://userweb.kernel.org/~tj/misc/slabh-sweep.py

    The script does the followings.

    * Scan files for gfp and slab usages and update includes such that
    only the necessary includes are there. ie. if only gfp is used,
    gfp.h, if slab is used, slab.h.

    * When the script inserts a new include, it looks at the include
    blocks and try to put the new include such that its order conforms
    to its surrounding. It's put in the include block which contains
    core kernel includes, in the same order that the rest are ordered -
    alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
    doesn't seem to be any matching order.

    * If the script can't find a place to put a new include (mostly
    because the file doesn't have fitting include block), it prints out
    an error message indicating which .h file needs to be added to the
    file.

    The conversion was done in the following steps.

    1. The initial automatic conversion of all .c files updated slightly
    over 4000 files, deleting around 700 includes and adding ~480 gfp.h
    and ~3000 slab.h inclusions. The script emitted errors for ~400
    files.

    2. Each error was manually checked. Some didn't need the inclusion,
    some needed manual addition while adding it to implementation .h or
    embedding .c file was more appropriate for others. This step added
    inclusions to around 150 files.

    3. The script was run again and the output was compared to the edits
    from #2 to make sure no file was left behind.

    4. Several build tests were done and a couple of problems were fixed.
    e.g. lib/decompress_*.c used malloc/free() wrappers around slab
    APIs requiring slab.h to be added manually.

    5. The script was run on all .h files but without automatically
    editing them as sprinkling gfp.h and slab.h inclusions around .h
    files could easily lead to inclusion dependency hell. Most gfp.h
    inclusion directives were ignored as stuff from gfp.h was usually
    wildly available and often used in preprocessor macros. Each
    slab.h inclusion directive was examined and added manually as
    necessary.

    6. percpu.h was updated not to include slab.h.

    7. Build test were done on the following configurations and failures
    were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my
    distributed build env didn't work with gcov compiles) and a few
    more options had to be turned off depending on archs to make things
    build (like ipr on powerpc/64 which failed due to missing writeq).

    * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
    * powerpc and powerpc64 SMP allmodconfig
    * sparc and sparc64 SMP allmodconfig
    * ia64 SMP allmodconfig
    * s390 SMP allmodconfig
    * alpha SMP allmodconfig
    * um on x86_64 SMP allmodconfig

    8. percpu.h modifications were reverted so that it could be applied as
    a separate patch and serve as bisection point.

    Given the fact that I had only a couple of failures from tests on step
    6, I'm fairly confident about the coverage of this conversion patch.
    If there is a breakage, it's likely to be something in one of the arch
    headers which should be easily discoverable easily on most builds of
    the specific arch.

    Signed-off-by: Tejun Heo <tj@kernel.org>
    Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
    Cc: Ingo Molnar <mingo@redhat.com>
    Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>

    Tejun Heo
     

25 Mar, 2010

5 commits