Since ODP had a single struct mmu_notifier located in the ucontext it
could only handle a single MM at a time, and this prevented it from using
the new owning_mm system.
With the prior rework it is now simple to let ODP track multiple MMs per
ucontext, finish the job so that the per_mm is allocated on a mm by mm
basis, and freed when the last umem is dropped from the ucontext.
As a side effect the new saner locking removes the lockdep splat about
nesting the umem_rwsem between mmu_notifier_unregister and
ib_umem_odp_release.
It also makes ODP work with multiple processes, across, fork, etc.
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
This is the first step to make ODP use the owning_mm that is now part of
struct ib_umem.
Each ODP umem is linked to a single per_mm structure, which in turn, is
linked to a single mm, via the embedded mmu_notifier. This first patch
introduces the structure and reworks eveything to use it.
This also needs to introduce tgid into the ib_ucontext_per_mm, as
get_user_pages_remote() requires the originating task for statistics
tracking.
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
This no longer has any use, we can use container_of to get to the
umem_odp, and a simple flag to indicate if this is an odp MR. Remove the
few remaining references to it.
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
These two structures are linked together, use the container_of pattern
instead of a double allocation to make the code simpler and easier to
follow.
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
All of these functions already require the ODP version of the umem struct,
make this very clear by having the signature require it. This paves the
way to using the container_of() pattern to link umem_odp and umem
together.
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
This is just wrong, the process that calls into the reg_mr is the process
associated with the umem, and that does not have to be the same process
that created the context.
When this code was first written mmgrab() didn't exist, however these days
we can just directly hold the mm_struct pointer in the umem and have no
ambiguity when it comes to releasing the umem as to which mm it was
associated with.
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
The disassociate_ucontext function in every driver is now empty, so we
don't need this ugly and wrong code that was messing with tgids.
rdma_user_mmap_io does this same work in a better way.
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
To support disassociation and PCI hot unplug, we have to track all the
VMAs that refer to the device IO memory. When disassociation occurs the
VMAs have to be revised to point to the zero page, not the IO memory, to
allow the physical HW to be unplugged.
The three drivers supporting this implemented three different versions
of this algorithm, all leaving something to be desired. This new common
implementation has a few differences from the driver versions:
- Track all VMAs, including splitting/truncating/etc. Tie the lifetime of
the private data allocation to the lifetime of the vma. This avoids any
tricks with setting vm_ops which Linus didn't like. (see link)
- Support multiple mms, and support properly tracking mmaps triggered by
processes other than the one first opening the uverbs fd. This makes
fork behavior of disassociation enabled drivers the same as fork support
in normal drivers.
- Don't use crazy get_task stuff.
- Simplify the approach for to racing between vm_ops close and
disassociation, fixing the related bugs most of the driver
implementations had. Since we are in core code the tracking list can be
placed in struct ib_uverbs_ufile, which has a lifetime strictly longer
than any VMAs created by mmap on the uverbs FD.
Link: https://www.spinics.net/lists/stable/msg248747.html
Link: https://lkml.kernel.org/r/CA+55aFxJTV_g46AQPoPXen-UPiqR1HGMZictt7VpC-SMFbm3Cw@mail.gmail.com
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
The error path has several mistakes
- cdev_del should not be called if cdev_device_add fails
- We must call put_device on all the goto exit paths as that is what frees
the uapi, SRCU and the struct itself.
While we are here consolidate all the uvdev_dev init that cannot fail at
the top.
Fixes: c5c4d92e70 ("RDMA/uverbs: Use cdev_device_add() instead of cdev_add()")
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Reviewed-by: Parav Pandit <parav@mellanox.com>
rdma_set_src_addr_rcu should check copy_src_l2_addr fails, rather than
always return 0. Also copy_src_l2_addr should return 'ret' as its return
value when rdma_translate_ip fails.
Fixes: c31d4b2ddf ("RDMA/core: Protect against changing dst->dev during destination resolve")
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Reviewed-by: Parav Pandit <parav@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
This does nothing but indicate if the uverbs_file is in the device's list,
use list_del_init instead.
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
When resolving destination address or route, when net namespace is
unavailable, refer to the net namespace of the netdevice of the SGID
attribute. This is typically the case for requests arriving from the
network for RoCE ports.
Signed-off-by: Parav Pandit <parav@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Introduce an API rdma_read_gid_attr_ndev_rcu() to return GID attribute
netdevice which is in UP state for accessing netdevice's fields such as
net namespace and ifindex.
This is useful for users who intent to access netdevice fields under rcu
lock.
Signed-off-by: Parav Pandit <parav@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Currently RoCE route resolve functionality is split between two
functions. (a) roce_resolve_route_from_path() and its helper function
rdma_resolve_ip_route().
Due to this multiple sockaddr src structures are created in both functions
with rdma_dev_addr is an interface between the two for checks.
Since there is only one user of rdma_resolve_ip_route() as RoCE, combine
the functionality of both functions to roce_resolve_route_from_path() and
further reduce the scope of rdma_dev_addr to core/addr.c
This also allow to extend addr_resolve() in subsequent patch to consider
netdev properties of GID in safer way under rcu lock.
Additionally src and dst addresses were always provided, so skip the src
addr NULL pointer check as they are present on the stack now.
Signed-off-by: Parav Pandit <parav@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
During resolving address process, during route lookup and while performing
src address translation in case of loopback mode, hold the rcu lock so
that if netdevice is moving to different net namespace, or being
unregistered, it can be synchronized with net/core/dev.c, ie
change_net_namespace()
->dev_close_many()
->rt6_uncached_list_flush_dev() who would change dst->dev
to loopback device of the given net namespace.
Therefore, hold the rcu lock and sync with synchronize_net() of
change_net_namespace() to ensure that netdevice cannot get freed while
dst->dev is being used.
Signed-off-by: Parav Pandit <parav@mellanox.com>
Reviewed-by: Daniel Jurgens <danielj@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Set and refer to rdma_dev_addr network type instead of dst->ndev to reduce
dependency on accessing dst netdevice.
Signed-off-by: Parav Pandit <parav@mellanox.com>
Reviewed-by: Daniel Jurgens <danielj@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Use common code flow for resolving neighbour and for finding source
addresses.
Signed-off-by: Parav Pandit <parav@mellanox.com>
Reviewed-by: Daniel Jurgens <danielj@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Now that rdma_copy_addr() only copies the source addresses and all callers
are interested in copying only source addresses, simplify it to drop the
destination address argument.
Given that it only copies source layer2 addresses, rename it to
rdma_copy_src_l2_addr for better code readability.
Signed-off-by: Parav Pandit <parav@mellanox.com>
Reviewed-by: Daniel Jurgens <danielj@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
rdma_translate_ip() is done while resolving address for the loopback
addresses. The current flow is convoluted with resolve neighbor being
optional.
This patch simplifies the code in following ways.
(a) Use common code between IPv4 and IPv6 for address translation,
loopback checks and acquiring netdevice.
(b) During neigh resolve in addr_resolve_neigh(), only copy destination
address.
(c) Always resolve the source address before the destination address,
because it doesn't depend on resolving neigh being requested or not.
This helps to reduce 3 calls of rdma_copy_addr and rdma_translate_ip to
one and makes it easier to follow the code flow.
Now that ib_nl_fetch_ha() doesn't depend on dst, drop dst argument from
ib_nl_fetch_ha().
Signed-off-by: Parav Pandit <parav@mellanox.com>
Reviewed-by: Daniel Jurgens <danielj@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Current code typecasts destination address using extra variable but uses
source address as is.
Even though the compiler optimizes such code well, just let each protocol
specific function typecast for src and dest both and have symmetric code.
Signed-off-by: Parav Pandit <parav@mellanox.com>
Reviewed-by: Daniel Jurgens <danielj@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
addr4_resolve() and addr6_resolve() are called by checking the value of
sa_family.
Both above functions overwrite the value after typecasting, this is not
necessary.
Signed-off-by: Parav Pandit <parav@mellanox.com>
Reviewed-by: Daniel Jurgens <danielj@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
This fixes two issues:
1. When address family is other than IPv4 or v6, rdma_translate_ip()
returns success which is incorrect.
2. When address familty is AF_INET6, and if the source address is not
found, it returns success, which is also incorrect.
Therefore, introduce and use rdma_find_ndev_for_src_ip_rcu() helper
function which returns correct success or error status and is also useful
for future code refactor in addr_resolve().
Signed-off-by: Parav Pandit <parav@mellanox.com>
Reviewed-by: Daniel Jurgens <danielj@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Support attaching flow actions to a flow rule via raw create flow.
For now only NIC RX path is supported. This change requires to export
flow resources management functions so we can maintain proper bookkeeping
of flow actions.
Signed-off-by: Mark Bloch <markb@mellanox.com>
Reviewed-by: Yishai Hadas <yishaih@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Use ib_set_flow() when initializing flow related resources.
Signed-off-by: Mark Bloch <markb@mellanox.com>
Reviewed-by: Yishai Hadas <yishaih@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Methods sometimes need to get a flexible set of IDRs and not a strict set
as can be achieved today by the conventional IDR attribute. Add a new
IDRS_ARRAY attribute to the generic uverbs ioctl layer.
IDRS_ARRAY points to array of idrs of the same object type and same access
rights, only write and read are supported.
Signed-off-by: Guy Levi <guyle@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>``
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Even though device->ifindex is assigned before adding the device in the
list which is read by netlink flow, it is better to assign rdma device
index before publishing the device in the system to users and clients.
Signed-off-by: Parav Pandit <parav@mellanox.com>
Reviewed-by: Daniel Jurgens <danielj@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
During register_device() init sequence is,
(a) register with rdma cgroup followed by
(b) register with sysfs
Therefore, unregister_device() sequence should follow the reverse order.
Signed-off-by: Parav Pandit <parav@mellanox.com>
Reviewed-by: Daniel Jurgens <danielj@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Lockdep engine handles correctly downgrade of locks and it simply
incorrect to disable lockdep checks prior to calling mmu_notifier.
Remove lockdep_off and ensure locks correctness.
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Even though device registration/unregistration and client
registration/unregistration is not a performance path, define the
client_data_lock as rwlock for code clarity.
Signed-off-by: Parav Pandit <parav@mellanox.com>
Reviewed-by: Daniel Jurgens <danielj@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
add_client_context(), ib_unregister_device() and ib_unregister_client()
are designed to call from blocking context. There is no need to save and
restore last interrupt state when called from such blocking context. Even
though this is not a performance path, using the right spin lock API is
desired for code clarity.
To avoid checkpatch warning while removing flags, sizeof() is used.
Signed-off-by: Parav Pandit <parav@mellanox.com>
Reviewed-by: Daniel Jurgens <danielj@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
While unregistering a device, remove the context elements from the list to
not have any stale entries. With that any errors/bugs can be checked when
device is freed.
Signed-off-by: Parav Pandit <parav@mellanox.com>
Reviewed-by: Daniel Jurgens <danielj@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
While traversing client_data_list in following conditions, linked list is
only read, no elements of the list are removed. Therefore, use
list_for_each_entry(), instead of list_for_each_safe().
Signed-off-by: Parav Pandit <parav@mellanox.com>
Reviewed-by: Daniel Jurgens <danielj@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
While unregistering a client, only context removal should be protected
with lock. There is no need to protect a freeing of such context which is
already removed from the list.
Signed-off-by: Parav Pandit <parav@mellanox.com>
Reviewed-by: Daniel Jurgens <danielj@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Currently rdma_addr_cancel() is an async operation, which notifies that
cancel is done by executing the callback function given during
rdma_resolve_ip(). If resolve_ip request is already completed than
callback is not executed.
Instead, now rdma_resolve_addr() and rdma_addr_cancel() simplified in
following ways.
1. rdma_addr_cancel() now a synchronous method. If request was
pending, after it is cancelled, no callback is notified.
2. rdma_resolve_addr() and respective addr_handler() callback doesn't
need to hold reference to cm_id.
Signed-off-by: Parav Pandit <parav@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
While registering a mad agent, a user space can trigger various errors
and flood the logs.
Therefore, decrease verbosity and rate limit such error messages.
While we are at it, use __func__ to print function name.
Signed-off-by: Parav Pandit <parav@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Reviewed-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
When requested QP type is not supported for a {device, port}, return the
error right away before validating all parameters during mad agent
registration time.
Signed-off-by: Parav Pandit <parav@mellanox.com>
Reviewed-by: Daniel Jurgens <danielj@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
For dependencies, branch based on rdma.git 'for-rc' of
https://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma.git/
Pull 'uverbs_dev_cleanups' from Leon Romanovsky:
====================
Reuse the char device code interfaces to simplify ib_uverbs_device
creation and destruction. As part of this series, we are sending fix to
cleanup path, which was discovered during internal review,
The fix definitely can go to -rc, but it means that this series will be
dependent on rdma-rc.
====================
* branch 'uverbs_dev_cleanups':
RDMA/uverbs: Use device.groups to initialize device attributes
RDMA/uverbs: Use cdev_device_add() instead of cdev_add()
RDMA/core: Depend on device_add() to add device attributes
RDMA/uverbs: Fix error cleanup path of ib_uverbs_add_one()
Resolved conflict in ib_device_unregister_sysfs()
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Instead of explicitly adding device attribute files and handling such
error conditions, depend on device core layer to create device attributes
files based group pointer NULL terminated array.
Signed-off-by: Parav Pandit <parav@mellanox.com>
Reviewed-by: Daniel Jurgens <danielj@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Instead of doing two step process to add char device and create underlying
device, use cdev_device_add() which does both.
Currently a kobject per uverbs_device is created to keep reference to its
holding ib_uverbs_device in addition to its underlying device 'dev'.
Instead just use uverbs_device->dev to keep a reference to.
With this change there is single reference tracker for ib_uverbs_device
structure.
This allows for subsequent patch to registers group attribute as well
using single API cdev_device_add().
Signed-off-by: Parav Pandit <parav@mellanox.com>
Reviewed-by: Daniel Jurgens <danielj@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Instead of adding/removing device attribute files, depend on device_add()
which considers adding these device files based on NULL terminated
attributes group array.
Signed-off-by: Parav Pandit <parav@mellanox.com>
Reviewed-by: Daniel Jurgens <danielj@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
If ib_uverbs_create_uapi() fails, dev_num should be freed from the bitmap.
Fixes: 7d96c9b176 ("IB/uverbs: Have the core code create the uverbs_root_spec")
Signed-off-by: Parav Pandit <parav@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Reuse existing get_device() API to do it symmetric to already used
put_device() in commit 924b8900a4 ("RDMA/core: Replace open-coded
variant of put_device")
Signed-off-by: Parav Pandit <parav@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
The "closing" variable is used as boolean and set to "true" in one
place, update the declaration of that variable and their other
assignment to proper type.
Fixes: e951747a08 ("IB/uverbs: Rework the locking for cleaning up the ucontext")
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
The upstream kernel commit cited below modified the workqueue in the
new CQ API to be bound to a specific CPU (instead of being unbound).
This caused ALL users of the new CQ API to use the same bound WQ.
Specifically, MAD handling was severely delayed when the CPU bound
to the WQ was busy handling (higher priority) interrupts.
This caused a delay in the MAD "heartbeat" response handling,
which resulted in ports being incorrectly classified as "down".
To fix this, add a new "unbound" WQ type to the new CQ API, so that users
have the option to choose either a bound WQ or an unbound WQ.
For MADs, choose the new "unbound" WQ.
Fixes: b7363e67b2 ("IB/device: Convert ib-comp-wq to be CPU-bound")
Signed-off-by: Jack Morgenstein <jackm@dev.mellanox.co.il>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.m>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Refactor the initialization of a flow action object to a common function.
Signed-off-by: Mark Bloch <markb@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
This makes it clear and safe to access constants passed in from user
space. We define a consistent ABI of u64 for all constants, and verify
that the data passed in can be represented by the type the user supplies.
The expectation is this will always be used with an enum declaring the
constant values, and the user will use the enum type as input to the
accessor.
To retrieve the attribute value we introduce two helper calls - one
standard which may fail if attribute is not valid and one where caller can
provide a default value which will be used in case the attribute is not
valid (useful when attribute is optional).
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Ariel Levkovich <lariel@mellanox.com>
Signed-off-by: Mark Bloch <markb@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
The object lock was supposed to always be released during destroy, but
when the destruction retry series was integrated with the destroy series
it created a failure path that missed the unlock.
Keep with convention, if destroy fails the caller must undo all locking.
Fixes: 87ad80abc7 ("IB/uverbs: Consolidate uobject destruction")
Signed-off-by: Artemy Kovalyov <artemyko@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
The current code grabs the private_data of whatever file descriptor
userspace has supplied and implicitly casts it to a `struct ucma_file *`,
potentially causing a type confusion.
This is probably fine in practice because the pointer is only used for
comparisons, it is never actually dereferenced; and even in the
comparisons, it is unlikely that a file from another filesystem would have
a ->private_data pointer that happens to also be valid in this context.
But ->private_data is not always guaranteed to be a valid pointer to an
object owned by the file's filesystem; for example, some filesystems just
cram numbers in there.
Check the type of the supplied file descriptor to be safe, analogous to how
other places in the kernel do it.
Fixes: 88314e4dda ("RDMA/cma: add support for rdma_migrate_id()")
Signed-off-by: Jann Horn <jannh@google.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
There are several blockable mmu notifiers which might sleep in
mmu_notifier_invalidate_range_start and that is a problem for the
oom_reaper because it needs to guarantee a forward progress so it cannot
depend on any sleepable locks.
Currently we simply back off and mark an oom victim with blockable mmu
notifiers as done after a short sleep. That can result in selecting a new
oom victim prematurely because the previous one still hasn't torn its
memory down yet.
We can do much better though. Even if mmu notifiers use sleepable locks
there is no reason to automatically assume those locks are held. Moreover
majority of notifiers only care about a portion of the address space and
there is absolutely zero reason to fail when we are unmapping an unrelated
range. Many notifiers do really block and wait for HW which is harder to
handle and we have to bail out though.
This patch handles the low hanging fruit.
__mmu_notifier_invalidate_range_start gets a blockable flag and callbacks
are not allowed to sleep if the flag is set to false. This is achieved by
using trylock instead of the sleepable lock for most callbacks and
continue as long as we do not block down the call chain.
I think we can improve that even further because there is a common pattern
to do a range lookup first and then do something about that. The first
part can be done without a sleeping lock in most cases AFAICS.
The oom_reaper end then simply retries if there is at least one notifier
which couldn't make any progress in !blockable mode. A retry loop is
already implemented to wait for the mmap_sem and this is basically the
same thing.
The simplest way for driver developers to test this code path is to wrap
userspace code which uses these notifiers into a memcg and set the hard
limit to hit the oom. This can be done e.g. after the test faults in all
the mmu notifier managed memory and set the hard limit to something really
small. Then we are looking for a proper process tear down.
[akpm@linux-foundation.org: coding style fixes]
[akpm@linux-foundation.org: minor code simplification]
Link: http://lkml.kernel.org/r/20180716115058.5559-1-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Acked-by: Christian König <christian.koenig@amd.com> # AMD notifiers
Acked-by: Leon Romanovsky <leonro@mellanox.com> # mlx and umem_odp
Reported-by: David Rientjes <rientjes@google.com>
Cc: "David (ChunMing) Zhou" <David1.Zhou@amd.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: David Airlie <airlied@linux.ie>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: Doug Ledford <dledford@redhat.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Mike Marciniszyn <mike.marciniszyn@intel.com>
Cc: Dennis Dalessandro <dennis.dalessandro@intel.com>
Cc: Sudeep Dutt <sudeep.dutt@intel.com>
Cc: Ashutosh Dixit <ashutosh.dixit@intel.com>
Cc: Dimitri Sivanich <sivanich@sgi.com>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: "Jérôme Glisse" <jglisse@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Felix Kuehling <felix.kuehling@amd.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
rdma.git merge resolution for the 4.19 merge window
Conflicts:
drivers/infiniband/core/rdma_core.c
- Use the rdma code and revise with the new spelling for
atomic_fetch_add_unless
drivers/nvme/host/rdma.c
- Replace max_sge with max_send_sge in new blk code
drivers/nvme/target/rdma.c
- Use the blk code and revise to use NULL for ib_post_recv when
appropriate
- Replace max_sge with max_recv_sge in new blk code
net/rds/ib_send.c
- Use the net code and revise to use NULL for ib_post_recv when
appropriate
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
