We call put_device() in the error path, which is fine for dev==NULL.
However, in case kobject_set_name_vargs() fails, we have dev!=NULL but
device_initialized() wasn't called, yet.
Fix this by splitting device_register() into explicit calls to
device_add() and an early call to device_initialize().
Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
With CONFIG_DEBUG_KOBJECT_RELEASE=y, removing and immediately reloading the
dmi-sysfs module causes the following warning:
sysfs: cannot create duplicate filename '/firmware/dmi'
kobject_add_internal failed for dmi with -EEXIST, don't try to register things with the same name in the same directory.
The "dmi" directory stays in sysfs until the dmi_kobj is released, and
DEBUG_KOBJECT_RELEASE delays that.
I don't think we can hit this problem in normal usage because dmi_kobj is
static and nothing outside dmi-sysfs can get a reference to it, so the
only way to delay the "dmi" release is with DEBUG_KOBJECT_RELEASE.
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Removing the dmi-sysfs module causes the following warning:
# modprobe -r dmi_sysfs
WARNING: CPU: 11 PID: 6785 at fs/sysfs/inode.c:325 sysfs_hash_and_remove+0xa9/0xb0()
sysfs: can not remove 'raw', no directory
This is because putting the entry kobject, e.g., for
"/sys/firmware/dmi/entries/19-0", removes the directory and all its
contents. By the time dmi_sysfs_entry_release() runs, the "raw" file
inside ".../19-0/" has already been removed.
Therefore, we don't need to remove the "raw" bin file at all in
dmi_sysfs_entry_release().
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The commit [3e358ac2bb: firmware: Be a bit more verbose about direct
firmware loading failure] introduced a new warning message about
falling back to user helper, but this isn't true when
CONFIG_FW_LOADER_USER_HELPER isn't set.
In this patch, clear the FW_OPT_FALLBACK flag in the case without
userhelper, so that the corresponding code will be disabled.
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
More than two boolean arguments to a function are rather confusing and
error-prone for callers. Let's make the behavior bit flags instead of
triple combos.
A nice suggestion by Borislav Petkov.
Acked-by: Borislav Petkov <bp@suse.de>
Acked-by: Prarit Bhargava <prarit@redhat.com>
Acked-by: Ming Lei <ming.lei@canonical.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Use the new helper, request_firmware_direct(), for avoiding the
lengthy timeout of non-existing firmware loads. Especially the Intel
microcode driver suffers from this problem because each CPU triggers
the f/w loading, thus it ends up taking (literally) hours with many
cores.
Tested-by: Prarit Bhargava <prarit@redhat.com>
Acked-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When CONFIG_FW_LOADER_USER_HELPER is set, request_firmware() falls
back to the usermode helper for loading via udev when the direct
loading fails. But the recent udev takes way too long timeout (60
seconds) for non-existing firmware. This is unacceptable for the
drivers like microcode loader where they load firmwares optionally,
i.e. it's no error even if no requested file exists.
This patch provides a new helper function, request_firmware_direct().
It behaves as same as request_firmware() except for that it doesn't
fall back to usermode helper but returns an error immediately if the
f/w can't be loaded directly in kernel.
Without CONFIG_FW_LOADER_USER_HELPER=y, request_firmware_direct() is
just an alias of request_firmware(), due to obvious reason.
Tested-by: Prarit Bhargava <prarit@redhat.com>
Acked-by: Ming Lei <ming.lei@canonical.com>
Acked-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If the call to kvasprintf fails then the old name of the object will be leaked,
this patch fixes the bug by restoring the old name before returning ENOMEM.
Signed-off-by: Maurizio Lombardi <mlombard@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There's no "unlink from sysfs" interface for ksets, so I think callers of
kset_unregister() expect the kset to be removed from sysfs immediately,
without waiting for the last reference to be released.
This patch makes the sysfs removal happen immediately, so the caller may
create a new kset with the same name as soon as kset_unregister() returns.
Without this, every caller has to call "kobject_del(&kset->kobj)" first
unless it knows it will never create a new kset with the same name.
This sometimes shows up on module unload and reload, where the reload fails
because it tries to create a kobject with the same name as one from the
original load that still exists. CONFIG_DEBUG_KOBJECT_RELEASE=y makes this
problem easier to hit.
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When CONFIG_DEBUG_KOBJECT_RELEASE=y, delay kobject release functions for a
random time between 1 and 8 seconds, which effectively changes the order in
which they're called.
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
kernfs inherited "security.*" xattr support from sysfs. This patch
extends xattr support to "trusted.*" using simple_xattr_*(). As
trusted xattrs are restricted to CAP_SYS_ADMIN, simple_xattr_*() which
uses kernel memory for storage shouldn't be problematic.
Note that the existing "security.*" support doesn't implement
get/remove/list and the this patch only implements those ops for
"trusted.*". We probably want to extend those ops to include support
for "security.*".
This patch will allow using kernfs from cgroup which requires
"trusted.*" xattr support.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: David P. Quigley <dpquigl@tycho.nsa.gov>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
sysfs_init_inode_attrs() is a bit clumsy to use requiring the caller
to check whether @sd->s_iattr is already set or not. Rename it to
sysfs_inode_attrs(), update it to check whether @sd->s_iattr is
already initialized before trying to initialize it and return
@sd->s_iattr. This simplifies the callers.
While at it,
* Rename struct sysfs_inode_attrs pointer variables to "attrs". As
kernfs no longer deals with "struct attribute", this isn't confusing
and makes it easier to distinguish from struct iattr pointers.
* A new field will be added to sysfs_inode_attrs. Reindent in
preparation.
This patch doesn't introduce any behavior changes.
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Previously, example_init() leaked a kset if any of the object creations
failed. This fixes the leak by calling kset_unregister() in the error
path.
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
fs/kernfs/kernfs-internal.h needed to include fs/sysfs/sysfs.h because
part of kernfs core implementation was living in sysfs.
fs/sysfs/sysfs.h needed to include fs/kernfs/kernfs-internal.h because
include/linux/kernfs.h didn't expose enough interface.
The separation is complete and neither is true anymore. Remove the
cross inclusion and make sysfs a proper user of kernfs.
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
fs/sysfs/symlink.c::sysfs_delete_link() tests @sd->s_flags for
SYSFS_FLAG_NS. Let's add kernfs_ns_enabled() so that sysfs doesn't
have to test sysfs_dirent flag directly. This makes things tidier for
kernfs proper too.
This is purely cosmetic.
v2: To avoid possible NULL deref, use noop dummy implementation which
always returns false when !CONFIG_SYSFS.
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
sysfs_dirent includes some information which should be available to
kernfs users - the type, flags, name and parent pointer. This patch
moves sysfs_dirent definition from kernfs/kernfs-internal.h to
include/linux/kernfs.h so that kernfs users can access them.
The type part of flags is exported as enum kernfs_node_type, the flags
kernfs_node_flag, sysfs_type() and kernfs_enable_ns() are moved to
include/linux/kernfs.h and the former is updated to return the enum
type. sysfs_dirent->s_parent and ->s_name are marked explicitly as
public.
This patch doesn't introduce any functional changes.
v2: Flags exported too and kernfs_enable_ns() definition moved.
v3: While moving kernfs_enable_ns() to include/linux/kernfs.h, v1 and
v2 put the definition outside CONFIG_SYSFS replacing the dummy
implementation with the actual implementation too. Unfortunately,
this can lead to oops when !CONFIG_SYSFS because
kernfs_enable_ns() may be called on a NULL @sd and now tries to
dereference @sd instead of not doing anything. This issue was
reported by Yuanhan Liu.
Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: Yuanhan Liu <yuanhan.liu@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Move core mount code to fs/kernfs/mount.c. The respective
declarations in fs/sysfs/sysfs.h are moved to
fs/kernfs/kernfs-internal.h.
This is pure relocation.
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We're in the process of separating out core sysfs functionality into
kernfs which will deal with sysfs_dirents directly. This patch
rearranges mount path so that the kernfs and sysfs parts are separate.
* As sysfs_super_info won't be visible outside kernfs proper,
kernfs_super_ns() is added to allow kernfs users to access a
super_block's namespace tag.
* Generic mount operation is separated out into kernfs_mount_ns().
sysfs_mount() now just performs sysfs-specific permission check,
acquires namespace tag, and invokes kernfs_mount_ns().
* Generic superblock release is separated out into kernfs_kill_sb()
which can be used directly as file_system_type->kill_sb(). As sysfs
needs to put the namespace tag, sysfs_kill_sb() wraps
kernfs_kill_sb() with ns tag put.
* sysfs_dir_cachep init and sysfs_inode_init() are separated out into
kernfs_init(). kernfs_init() uses only small amount of memory and
trying to handle and propagate kernfs_init() failure doesn't make
much sense. Use SLAB_PANIC for sysfs_dir_cachep and make
sysfs_inode_init() panic on failure.
After this change, kernfs_init() should be called before
sysfs_init(), fs/namespace.c::mnt_init() modified accordingly.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: linux-fsdevel@vger.kernel.org
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
kernfs is being updated to allow multiple sysfs_dirent hierarchies so
that it can also be used by other users. Currently, sysfs
super_blocks are always attached to one kernfs_root - sysfs_root - and
distinguished only by their namespace tags.
This patch adds sysfs_super_info->root and update
sysfs_fill/test_super() so that super_blocks are identified by the
combination of both the associated kernfs_root and namespace tag.
This allows mounting different kernfs hierarchies.
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
kernfs is being updated to allow multiple sysfs_dirent hierarchies so
that it can also be used by other users. Currently, inode number is
allocated using a global ida, sysfs_ino_ida; however, inos for
different hierarchies should be handled separately.
This patch makes ino allocation per kernfs_root. sysfs_ino_ida is
replaced by kernfs_root->ino_ida and sysfs_new_dirent() is updated to
take @root and allocate ino from it. ida_simple_get/remove() are used
instead of sysfs_ino_lock and sysfs_alloc/free_ino().
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There currently is single kernfs hierarchy in the whole system which
is used for sysfs. kernfs needs to support multiple hierarchies to
allow other users. This patch introduces struct kernfs_root which
serves as the root of each kernfs hierarchy and implements
kernfs_create/destroy_root().
* Each kernfs_root is associated with a root sd (sysfs_dentry). The
root is freed when the root sd is released and kernfs_destory_root()
simply invokes kernfs_remove() on the root sd. sysfs_remove_one()
is updated to handle release of the root sd. Note that ps_iattr
update in sysfs_remove_one() is trivially updated for readability.
* Root sd's are now dynamically allocated using sysfs_new_dirent().
Update sysfs_alloc_ino() so that it gives out ino from 1 so that the
root sd still gets ino 1.
* While kernfs currently only points to the root sd, it'll soon grow
fields which are specific to each hierarchy. As determining a given
sd's root will be necessary, sd->s_dir.root is added. This backlink
fits better as a separate field in sd; however, sd->s_dir is inside
union with space to spare, so use it to save space and provide
kernfs_root() accessor to determine the root sd.
* As hierarchies may be destroyed now, each mount needs to hold onto
the hierarchy it's attached to. Update sysfs_fill_super() and
sysfs_kill_sb() so that they get and put the kernfs_root
respectively.
* sysfs_root is replaced with kernfs_root which is dynamically created
by invoking kernfs_create_root() from sysfs_init().
This patch doesn't introduce any visible behavior changes.
v2: kernfs_create_root() forgot to set @sd->priv. Fixed.
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Currently, it's assumed that there's a single kernfs hierarchy in the
system anchored at sysfs_root which is defined as a global struct. To
allow other users of kernfs, this will be made dynamic. Introduce a
new global variable sysfs_root_sd which points to &sysfs_root and
convert all &sysfs_root users.
This patch doesn't introduce any behavior difference.
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
It has been very long since sysfs depended on vfs to keep track of
internal states and whether sysfs is mounted or not doesn't make any
difference to sysfs's internal operation.
In addition to init and filesystem type registration, sysfs_init()
invokes kern_mount() to create in-kernel mount of sysfs. This
internal mounting doesn't server any purpose anymore. Remove it.
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add const qualifier to sysfs_super_info->ns so that it's consistent
with other namespace tag usages in sysfs. Because kobject doesn't use
const qualifier for namespace tags, this ends up requiring an explicit
cast to drop const qualifier in free_sysfs_super_info().
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
sysfs_fill_super() takes three params - @sb, @data and @silent - but
uses only @sb. Drop the latter two.
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Move core symlink code to fs/kernfs/symlink.c. fs/sysfs/symlink.c now
only contains sysfs wrappers around kernfs interfaces. The respective
declarations in fs/sysfs/sysfs.h are moved to
fs/kernfs/kernfs-internal.h.
This is pure relocation.
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Move core file code to fs/kernfs/file.c. fs/sysfs/file.c now contains
sysfs kernfs_ops callbacks, sysfs wrappers around kernfs interfaces,
and sysfs_schedule_callback(). The respective declarations in
fs/sysfs/sysfs.h are moved to fs/kernfs/kernfs-internal.h.
This is pure relocation.
v2: Refreshed on top of the v2 of "sysfs, kernfs: prepare read path
for kernfs".
v3: Refreshed on top of the v3 of "sysfs, kernfs: prepare read path
for kernfs".
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Move core dir code to fs/kernfs/dir.c. fs/sysfs/dir.c now only
contains sysfs_warn_dup() and sysfs wrappers around kernfs interfaces.
The respective declarations in fs/sysfs/sysfs.h are moved to
fs/kernfs/kernfs-internal.h.
This is pure relocation.
v2: sysfs_symlink_target_lock was mistakenly relocated to kernfs. It
should remain with sysfs. Fixed.
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There's nothing sysfs-specific in fs/sysfs/inode.c. Move everything
in it to fs/kernfs/inode.c. The respective declarations in
fs/sysfs/sysfs.h are moved to fs/kernfs/kernfs-internal.h.
This is pure relocation.
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Move data structure, constant and basic accessor declarations from
fs/sysfs/sysfs.h to fs/kernfs/kernfs-internal.h. The two files
currently include each other. Once kernfs / sysfs separation is
complete, the cross inclusions will be removed. Inclusion protectors
are added to fs/sysfs/sysfs.h to allow cross-inclusion.
This patch doesn't introduce any functional changes.
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Introduce kernfs interface for finding, getting and putting
sysfs_dirents.
* sysfs_find_dirent() is renamed to kernfs_find_ns() and lockdep
assertion for sysfs_mutex is added.
* sysfs_get_dirent_ns() is renamed to kernfs_find_and_get().
* Macro inline dancing around __sysfs_get/put() are removed and
kernfs_get/put() are made proper functions implemented in
fs/sysfs/dir.c.
While the conversions are mostly equivalent, there's one difference -
kernfs_get() doesn't return the input param as its return value. This
change is intentional. While passing through the input increases
writability in some areas, it is unnecessary and has been shown to
cause confusion regarding how the last ref is handled.
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Currently, sysfs_dirent active_ref lockdep annotation uses
attribute->[s]key as the lockdep key, which forces
kernfs_create_file_ns() to assume that sysfs_dirent->priv is pointing
to a struct attribute which may not be true for non-sysfs users. This
patch restructures the lockdep annotation such that
* kernfs_ops contains lockdep_key which is used by default for files
created kernfs_create_file_ns().
* kernfs_create_file_ns_key() is introduced which takes an extra @key
argument. The created file will use the specified key for
active_ref lockdep annotation. If NULL is specified, lockdep for
the file is disabled.
* sysfs_add_file_mode_ns() is updated to use
kernfs_create_file_ns_key() with the appropriate key from the
attribute or NULL if ignore_lockdep is set.
This makes the lockdep annotation properly contained in kernfs while
allowing sysfs to cleanly keep its current behavior. This patch
doesn't introduce any behavior differences.
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We want to add one more SYSFS_FLAG_* but we can't use the next higher
bit, 0x10000, as the flag field is 16bits wide. The flags are
currently arranged weirdly - 8 bits are set aside for the type flags
when there are only three three used, the first flag starts at 0x1000
instead of 0x0100 and flag literals have 5 digits (20 bits) when only
4 digits can be used.
Rearrange them so that type bits are only the lowest four, flags start
at 0x0010 and similar flags are grouped.
This patch doesn't cause any behavior difference.
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Introduce kernfs interface to wake up poll(2) which takes and returns
sysfs_dirents.
sysfs_notify_dirent() is renamed to kernfs_notify() and sysfs_notify()
is updated so that it doesn't directly grab sysfs_mutex but acquires
the target sysfs_dirents using sysfs_get_dirent().
sysfs_notify_dirent() is reimplemented as a dumb inline wrapper around
kernfs_notify().
This patch doesn't introduce any behavior changes.
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
kernfs_ops currently only supports single_open() behavior which is
pretty restrictive. Add optional callbacks ->seq_{start|next|stop}()
which, when implemented, are invoked for seq_file traversal. This
allows full seq_file functionality for kernfs users. This currently
doesn't have any user and doesn't change any behavior.
v2: Refreshed on top of the updated "sysfs, kernfs: prepare read path
for kernfs".
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
sysfs_add_one() is a wrapper around __sysfs_add_one() which prints out
duplicate name warning if __sysfs_add_one() fails with -EEXIST. The
previous kernfs conversions moved all dup warnings to sysfs interface
functions and sysfs_add_one() doesn't have any user left.
Remove sysfs_add_one() and update __sysfs_add_one() to take its name.
This patch doesn't make any functional changes.
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Introduce kernfs interface to create a file which takes and returns
sysfs_dirents.
The actual file creation part is separated out from
sysfs_add_file_mode_ns() into kernfs_create_file_ns(). The former now
only decides the kernfs_ops to use and the file's size and invokes the
latter.
This patch doesn't introduce behavior changes.
v2: Dummy implementation for !CONFIG_SYSFS updated to return -ENOSYS.
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
After kernfs_ops and sysfs_dirent->s_attr.size addition, the
distinction between SYSFS_KOBJ_BIN_ATTR and SYSFS_KOBJ_ATTR is only
necessary while creating files to decide which kernfs_ops to use.
Afterwards, they behave exactly the same.
This patch removes SYSFS_KOBJ_BIN_ATTR along with sysfs_is_bin().
sysfs_add_file[_mode_ns]() are updated to take bool @is_bin instead of
@type.
This patch doesn't introduce any behavior changes. This completely
isolates the distinction between the two sysfs file types in the sysfs
layer proper.
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
sysfs sets the size of regular files unconditionally at PAGE_SIZE and
takes the size of bin files from bin_attribute. The latter is a
pretty bad interface which forces bin_attribute users to create a
separate copy of bin_attribute for each instance of the file -
e.g. pci resource files.
Add sysfs_dirent->s_attr.size so that the size can be specified
separately. This unifies inode init paths of ATTR and BIN_ATTR
identical and allows for generic size handling for kernfs.
Unfortunately, this grows the size of sysfs_dirent by sizeof(loff_t).
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We're in the process of separating out core sysfs functionality into
kernfs which will deal with sysfs_dirents directly. This patch
introduces kernfs_ops which hosts methods kernfs users implement and
updates fs/sysfs/file.c such that sysfs_kf_*() functions populate
kernfs_ops and kernfs_file_*() functions call the matching entries
from kernfs_ops.
kernfs_ops contains the following groups of methods.
* seq_show() - for kernfs files which use seq_file for reads.
* read() - for direct read implementations. Used iff seq_show() is
not implemented.
* write() - for writes.
* mmap() - for mmaps.
Notes:
* sysfs_elem_attr->ops is added so that kernfs_ops can be accessed
from sysfs_dirent. kernfs_ops() helper is added to verify locking
and access the field.
* SYSFS_FLAG_HAS_(SEQ_SHOW|MMAP) added. sd->s_attr->ops is accessible
only while holding active_ref and there are cases where we want to
take different actions depending on which ops are implemented.
These two flags cache whether the two ops are implemented for those.
* kernfs_file_*() no longer test sysfs type but chooses different
behaviors depending on which methods in kernfs_ops are implemented.
The conversions are trivial except for the open path. As
kernfs_file_open() now decides whether to allow read/write accesses
depending on the kernfs_ops implemented, the presence of methods in
kobjs and attribute_bin should be propagated to kernfs_ops.
sysfs_add_file_mode_ns() is updated so that it propagates presence /
absence of the callbacks through _empty, _ro, _wo, _rw kernfs_ops.
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
sysfs_open_file will be used as the primary handle for kernfs methods.
Move its definition from fs/sysfs/file.c to include/linux/kernfs.h and
mark the public and private fields.
This is pure relocation.
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We're in the process of separating out core sysfs functionality into
kernfs which will deal with sysfs_dirents directly. This patch
prepares the rest - open, release and poll. There isn't much to do.
Just renaming is enough. As sysfs_file_operations and
sysfs_bin_operations are identical now, use the same file_operations
for both - kernfs_file_operations.
This patch doesn't introduce any behavior changes.
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We're in the process of separating out core sysfs functionality into
kernfs which will deal with sysfs_dirents directly. This patch
rearranges mmap path so that the kernfs and sysfs parts are separate.
sysfs_kf_bin_mmap() which handles the interaction with bin_attribute
mmap method is factored out of sysfs_bin_mmap(), which is renamed to
kernfs_file_mmap(). All vma ops are renamed accordingly.
sysfs_bin_mmap() is updated such that it can be used for both file
types. This will eventually allow using the same file_operations for
both file types, which is necessary to separate out kernfs.
This patch doesn't introduce any behavior changes.
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We're in the process of separating out core sysfs functionality into
kernfs which will deal with sysfs_dirents directly. This patch
rearranges write path so that the kernfs and sysfs parts are separate.
kernfs_file_write() handles all boilerplate work including buffer
management and locking and invokes sysfs_kf_write() or
sysfs_kf_bin_write() depending on the file type which deals with the
interaction with kobj store or bin_attribute write method.
While this patch changes the order of some operations, it shouldn't
change any visible behavior.
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We're in the process of separating out core sysfs functionality into
kernfs which will deal with sysfs_dirents directly. This patch
rearranges read path so that the kernfs and sysfs parts are separate.
* Regular file read path is refactored such that
kernfs_seq_start/next/stop/show() handle all the boilerplate work
including locking and updating event count for poll, while
sysfs_kf_seq_show() deals with interaction with kobj show method.
* Bin file read path is refactored such that kernfs_file_direct_read()
handles all the boilerplate work including buffer management and
locking, while sysfs_kf_bin_read() deals with interaction with
bin_attribute read method.
kernfs_file_read() is added. It invokes either the seq_file or direct
read path depending on the file type. This will eventually allow
using the same file_operations for both file types, which is necessary
to separate out kernfs.
While this patch changes the order of some operations, it shouldn't
change any visible behavior.
v2: Dropped unnecessary zeroing of @count from sysfs_kf_seq_show().
Add comments explaining single_open() behavior. Both suggested by
Pavel.
v3: seq_stop() is called even after seq_start() failed.
kernfs_seq_start() updated so that it doesn't unlock
sysfs_open_file->mutex on failure so that kernfs_seq_stop()
doesn't try to unlock an already unlocked mutex. Reported by
Fengguang.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Introduce kernfs interface to manipulate a directory which takes and
returns sysfs_dirents.
create_dir() is renamed to kernfs_create_dir_ns() and its argumantes
and return value are updated. create_dir() usages are replaced with
kernfs_create_dir_ns() and sysfs_create_subdir() usages are replaced
with kernfs_create_dir(). Dup warnings are handled explicitly by
sysfs users of the kernfs interface.
sysfs_enable_ns() is renamed to kernfs_enable_ns().
This patch doesn't introduce any behavior changes.
v2: Dummy implementation for !CONFIG_SYSFS updated to return -ENOSYS.
v3: kernfs_enable_ns() added.
v4: Refreshed on top of "sysfs: drop kobj_ns_type handling, take #2"
so that this patch removes sysfs_enable_ns().
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
A directory sysfs_dirent points to the associated kobj. A regular or
bin file points to the associated [bin_]attribute. This patch
replaces sysfs_dirent->s_dir.kobj and ->s_attr.[bin_]attr with void *
->priv.
This is to prepare for kernfs interface so that sysfs can specify the
private data in the same way for directories and files. This lower
debuggability but not by much - the whole thing was overlaid in a
union anyway. If debuggability becomes an issue, we can later add
->priv accessors which explicitly check for the sysfs_dirent type and
performs casting.
This patch doesn't introduce any behavior difference.
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
