Add restrack annotations to track allocations of ucontexts.

Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

Add ability to track allocated ib_ucontext, which are limited
resource and worth to be visible by users.

Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

Make all of the write() handlers use a consistent flow

From Jason,

This series unifies all the write handlers to use a flow that is very
similar to the ioctl handler flow, including having the same basic
assumptions about extensible buffer handling and the same handler
function call signature.

Along the way this consolidates all the copy_to/from_user into a small
set of safe buffer accessor functions tailored to the usage here. These
accessors use the new dispatcher-controlled calling convention for ucore
data, and support a placement of the response that does not rely on the
cmd.response value.

Overall this brings in in strong bounds checking to all the write()
handlers and consistent enforcement of the zero-fill/zero-check
methodology for buffer extension.

The end result is a significant complexity reduction for all of the
handlers and creates a high degree of uniformity between the write,
write_ex, and ioctl handlers and dispatch flow.

Thanks

Jason Gunthorpe (12):
  RDMA/uverbs: Remove out_len checks that are now done by the core
  RDMA/uverbs: Use uverbs_attr_bundle to pass ucore for write/write_ex
  RDMA/uverbs: Get rid of the 'callback' scheme in the compat path
  RDMA/uverbs: Use uverbs_response() for remaining response copying
  RDMA/uverbs: Use uverbs_request() for request copying
  RDMA/uverbs: Use uverbs_request() and core for write_ex handlers
  RDMA/uverbs: Fill in the response for IB_USER_VERBS_EX_CMD_MODIFY_QP
  RDMA/uverbs: Simplify ib_uverbs_ex_query_device
  RDMA/uverbs: Add a simple iterator interface for reading the command
  RDMA/uverbs: Use the iterator for ib_uverbs_unmarshall_recv()
  RDMA/uverbs: Do not check the input length on create_cq/qp paths
  RDMA/uverbs: Use only attrs for the write() handler signature

 drivers/infiniband/core/rdma_core.h   |    5 +-
 drivers/infiniband/core/uverbs_cmd.c  | 1165 ++++++++++---------------
 drivers/infiniband/core/uverbs_main.c |   23 +-
 drivers/infiniband/core/uverbs_uapi.c |   23 +-
 include/rdma/uverbs_ioctl.h           |    9 +-
 5 files changed, 479 insertions(+), 746 deletions(-)

Signed-off-by: Doug Ledford <dledford@redhat.com>

All of the old arguments can be derived from the uverbs_attr_bundle
structure, so get rid of the redundant arguments. Most of the prior work
has been removing users of the arguments to allow this to be a simple
patch.

Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

If the user did not provide a long enough command buffer then the missing
bytes are forced to zero. There is no reason to check the length if a zero
value is OK.

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 has a very complicated memory layout, with two flex arrays. Use
the iterator API to make reading it clearer.

Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

Several methods have a command with a trailing flex array, and they
all open code some extraction scheme. Centralize this into a simple
iterator API.

Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

We truncate the response structure if there is not enough room in the
user buffer so there is no reason to have all the mess with finely managing
response_length. Just fully fill the attrs and truncate on copy.

Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

A response struct was defined, and userspace is providing it (but not
checking it). Fill it in and write it out.

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 write_ex handlers have this horrible boilerplate in every function to
do the zero extend/zero check and min size checks. This is now handled in
the core code via the meta-data, and the zero checks are handled by
uverbs_request(). Replace all the occurrences.

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 function properly zero-extends, and zero-checks if the user
buffer is not the same size as the kernel command struct.

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 function properly truncates and zero-fills the response which is the
standard used by the ioctl uAPI when working with user data.

Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

There is no reason for this. For response processing we simply need to
copy, truncate, and zero fill the response into whatever output buffer
was provided. Add a function uverbs_response() that does this
consistently.

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 creates a consistent way to access the two core buffers across write
and write_ex handlers.

Remove the open coded ucore conversion in the write/ex compatibility
handlers.

Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

write() methods must work with fixed sized structures as that is the only
way to know where the udata segment starts. The common udata code now
rejects any write() that has a response buffer shorter than the core's
response.

Thus all the checks of out_len for write methods are redundant and can be
removed.

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 current implementation of create QP requires contiguous memory, such a
requirement is problematic once the memory is fragmented or the system is
low in memory, it causes failures in dma_zalloc_coherent().

This patch takes advantage of the new mlx5_core API which allocates a
fragmented buffer. This makes the QP creation much more resilient to
memory fragmentation. Data-path code was adapted to the fact that WQEs can
cross buffers.

We also use the opportunity to fix some cosmetic legacy coding convention
errors which were in the feature scope.

Signed-off-by: Guy Levi <guyle@mellanox.com>
Reviewed-by: Majd Dibbiny <majd@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

The current implementation of create SRQ requires contiguous memory, such
a requirement is problematic once the memory is fragmented or the system
is low in memory, it causes failures in dma_zalloc_coherent().

This patch takes the advantage of the new mlx5_core API which allocates a
fragmented buffer, and makes the SRQ creation much more resilient to
memory fragmentation. Data-path code was adapted to the fact that WQEs can
cross buffers.

Signed-off-by: Guy Levi <guyle@mellanox.com>
Reviewed-by: Majd Dibbiny <majd@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>

FRWR memory registration is done with a series of calls and WRs.
1. ULP invokes ib_dma_map_sg()
2. ULP invokes ib_map_mr_sg()
3. ULP posts an IB_WR_REG_MR on the Send queue

Step 2 generates an iova. It is permissible for ULPs to change this
iova (with certain restrictions) between steps 2 and 3.

rxe_map_mr_sg captures the MR's iova but later when rxe processes the
REG_MR WR, it ignores the MR's iova field. If a ULP alters the MR's iova
after step 2 but before step 3, rxe never captures that change.

When the remote sends an RDMA Read targeting that MR, rxe looks up the
R_key, but the altered iova does not match the iova stored in the MR,
causing the RDMA Read request to fail.

Reported-by: Anna Schumaker <schumaker.anna@gmail.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

Allow a user to attach a DEVX counter via mlx5 raw flow creation. In order
to attach a counter we introduce a new attribute:

MLX5_IB_ATTR_CREATE_FLOW_ARR_COUNTERS_DEVX

A counter can be attached to multiple flow steering rules.

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>

QIB driver was added in 2010 with many BUG_ON(), most of them were cleaned
out after years of development and usages.

It looks like that it is safe now to remove rest of BUG_ONs.

Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Acked-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

There is a spelling mistake in a usnic_err error message, fix it.

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

drivers/infiniband/core/uverbs_cmd.c:1095:1-3: WARNING: PTR_ERR_OR_ZERO can be used

 Use PTR_ERR_OR_ZERO rather than if(IS_ERR(...)) + PTR_ERR

Generated by: scripts/coccinelle/api/ptr_ret.cocci

Fixes: 7106a976 ("RDMA/uverbs: Make write() handlers return 0 on success")
Signed-off-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

Fix spelling mistake in usnic_err error message

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

Have the core code initialize the driver_udata if the method has a udata
description. This is done using the same create_udata the handler was
supposed to call.

This makes ioctl consistent with the write and write_ex paths.

Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>

Now that we have metadata describing the command format the core code can
directly compute the udata pointers and all the really ugly
ib_uverbs_init_udata() calls can be removed from the handlers.

This means all the write() handlers are no longer sensitive to the layout
of the command buffer.

Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>

The core code needs to compute the udata so we may as well pass it in the
uverbs_attr_bundle instead of on the stack. This converts the simple case
of write_ex() which already has a core calculation.

Also change the write() path to use the attrs for ib_uverbs_init_udata()
instead of on the stack. This lets the write to write_ex compatibility
path continue to follow the lead of the _ex path.

Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>

The size meta-data in the prior patch describes the smallest acceptable
buffer for the write() interface. Globally check this in the core code.

This is necessary in the case of write() methods that have a driver udata
to prevent computing a negative udata buffer length.

The return code of -ENOSPC is chosen here as some of the handlers already
use this code, however many other handler use EINVAL.

Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>

We need the structure sizes to compute the location of the udata in the
core code. Annotate the sizes into the new macro language.

This is generated largely by script and checked by comparing against the
similar list in rdma-core.

Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>

The uverbs_attr_bundle already contains this pointer, and most methods
don't actually need it. Get rid of the redundant function argument.

Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>

Currently they return the command length, while all other handlers return
0. This makes the write path closer to the write_ex and ioctl path.

Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>

Now that we can add meta-data to the description of write() methods we
need to pass the uverbs_attr_bundle into all write based handlers so
future patches can use it as a container for any new data transferred out
of the core.

This is the first step to bringing the write() and ioctl() methods to a
common interface signature.

This is a simple search/replace, and we push the attr down into the uobj
and other APIs to keep changes minimal.

Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>

If the struct is used with a driver_udata it should have a trailing
driver_data flex array to mark it as having udata.

In most cases this forces the end of the struct to be aligned to u64 which
is needed to make the trailing driver_data naturally aligned.

Unfortunately We have a few cases where the base struct is not aligned to
8 bytes, these are marked with a u32 driver_data and userspace will check
for alignment issues when it compiles the driver.

Also remove the empty ib_uverbs_modify_qp_resp as nothing uses this.

pahole says there is no change to any struct sizes by this change.

Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>

There is a spelling mistake in the module description text, fix it.

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Reviewed-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

When the rdma device is getting removed, get resource info can race with
device removal, as below:

      CPU-0                                  CPU-1
    --------                               --------
    rdma_nl_rcv_msg()
       nldev_res_get_cq_dumpit()
          mutex_lock(device_lock);
          get device reference
          mutex_unlock(device_lock);        [..]
                                            ib_unregister_device()
                                            /* Valid reference to
                                             * device->dev exists.
                                             */
                                             ib_dealloc_device()

          [..]
          provider->fill_res_entry();

Even though device object is not freed, fill_res_entry() can get called on
device which doesn't have a driver anymore. Kernel core device reference
count is not sufficient, as this only keeps the structure valid, and
doesn't guarantee the driver is still loaded.

Similar race can occur with device renaming and device removal, where
device_rename() tries to rename a unregistered device. While this is fine
for devices of a class which are not net namespace aware, but it is
incorrect for net namespace aware class coming in subsequent series.  If a
class is net namespace aware, then the below [1] call trace is observed in
above situation.

Therefore, to avoid the race, keep a reference count and let device
unregistration wait until all netlink users drop the reference.

[1] Call trace:
kernfs: ns required in 'infiniband' for 'mlx5_0'
WARNING: CPU: 18 PID: 44270 at fs/kernfs/dir.c:842 kernfs_find_ns+0x104/0x120
libahci i2c_core mlxfw libata dca [last unloaded: devlink]
RIP: 0010:kernfs_find_ns+0x104/0x120
Call Trace:
kernfs_find_and_get_ns+0x2e/0x50
sysfs_rename_link_ns+0x40/0xb0
device_rename+0xb2/0xf0
ib_device_rename+0xb3/0x100 [ib_core]
nldev_set_doit+0x165/0x190 [ib_core]
rdma_nl_rcv_msg+0x249/0x250 [ib_core]
? netlink_deliver_tap+0x8f/0x3e0
rdma_nl_rcv+0xd6/0x120 [ib_core]
netlink_unicast+0x17c/0x230
netlink_sendmsg+0x2f0/0x3e0
sock_sendmsg+0x30/0x40
__sys_sendto+0xdc/0x160

Fixes: da5c8507 ("RDMA/nldev: add driver-specific resource tracking")
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 several rdma_cm module specific functions are declared in
core_priv.h file. Now that we have cma_priv.h file specific to rdma_cm
kernel module, move them from core_priv.h to cma_priv.h

Signed-off-by: Parav Pandit <parav@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

Add annotations to the uverbs_api structure indicating which driver
methods are called by the implementation. If the required method
is NULL the write API will be not be callable.

This effectively duplicates the cmd_mask system, however it does it by
expressing invariants required by the core code, not by delegating
decision making to the driver. This is another step toward eliminating
cmd_mask.

Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>

Now that we use struct uverbs_uapi to link the method functions to the
dispatcher there is no reason to have them be extern symbols.

Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>

This organizes the write commands into objects and links them to the
uverbs_api data structure. The command path is reworked to use uapi
instead of its internal structures.

The command mask is moved from a runtime check to a registration time
check in the uapi.

Since the write interface does not have the object ID as part of the
command, the radix bins are converted into linear lists to support the
lookup.

Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>

Bringing all uapi entry points into one place lets us deal with them
consistently. For instance the write, write_ex and ioctl paths can be
disabled when an API is not supported by the driver.

This will replace the uverbs_cmd_table static arrays.

Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>

If we can't destroy the object then we certainly shouldn't allow it be
created or used. Remove it from the uverbs_uapi in this case.

This also disables methods of other objects that have mandatory object
handle inputs - ie REG_DM_MR is now automatically removed if DM objects
cannot be created.

Typically drivers not supporting an interface will mark all of the
supporting functions as NULL, including destroy.

This is intended to automatically eliminate entire corner cases in the API
that are difficult to test.

Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>