Use existing function ntb_transport_tx_free_entry() instead of open coding
the check to see if there are outstanding tx descriptors.

Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>

ntb_transport_tx_free_entry() never returns 0 with the current
calculation. If head == tail, then it would return qp->tx_max_entry.
Change compare to tail >= head and when they are equal, a 0 would be
returned.

Fixes: e74bfeedad08 ("NTB: Add flow control to the ntb_netdev")
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: renlonglong <ren.longlong@h3c.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>

Currently when the transport receive packets after netdev has closed the
transport returns error and triggers tx errors to be incremented and
carrier to be stopped. There is no reason to return error if the device is
already closed. Drop the packet and return 0.

Fixes: e26a5843f7f5 ("NTB: Split ntb_hw_intel and ntb_transport drivers")
Reported-by: Yuan Y Lu <yuan.y.lu@intel.com>
Tested-by: Yuan Y Lu <yuan.y.lu@intel.com>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>

The tx tail index is not reset when the link goes down. This causes the
tail index to go out of sync when the link goes down and comes back up.
Refactor the ntb_qp_link_down_reset() and reset the tail index as well.

Fixes: 2849b5d70641 ("NTB: Reset transport QP link stats on down")
Reported-by: Yuan Y Lu <yuan.y.lu@intel.com>
Tested-by: Yuan Y Lu <yuan.y.lu@intel.com>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>

This patch removes the error checking for debugfs_create_dir in
ntb_hw_amd.c. This is because the DebugFS kernel API is developed
in a way that the caller can safely ignore the errors that
occur during the creation of DebugFS nodes. The debugfs APIs have
a IS_ERR() judge in start_creating() which can handle it
gracefully. so these checks are unnecessary.

Signed-off-by: Ruan Jinjie <ruanjinjie@huawei.com>
Acked-by: Sanjay R Mehta <sanju.mehta@amd.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>

Use memdup_user_nul() helper instead of open-coding to simplify the code.

Signed-off-by: Ruan Jinjie <ruanjinjie@huawei.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Reviewed-by: Dan Carpenter <dan.carpenter@linaro.org>
Reviewed-by: Serge Semin <fancer.lancer@gmail.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>

Make IS_ERR() judge the debugfs_create_dir() function return
in perf_setup_dbgfs().

Signed-off-by: Minjie Du <duminjie@vivo.com>
Reviewed-by: Serge Semin <fancer.lancer@gmail.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>

It is expected that most callers should _ignore_ the errors
return by debugfs_create_dir() in tool_setup_dbgfs()

Signed-off-by: Wang Ming <machel@vivo.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Reviewed-by: Dan Carpenter <dan.carpenter@linaro.org>
Reviewed-by: Serge Semin <fancer.lancer@gmail.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>

The debugfs_create_dir function returns ERR_PTR in case of error, and the
only correct way to check if an error occurred is 'IS_ERR' inline function.
This patch will replace the null-comparison with IS_ERR.

Signed-off-by: Anup Sharma <anupnewsmail@gmail.com>
Suggested-by: Ivan Orlov <ivan.orlov0322@gmail.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>

Remove pci_clear_master to simplify the code,
the bus-mastering is also cleared in do_pci_disable_device,
like this:
./drivers/pci/pci.c:2197
static void do_pci_disable_device(struct pci_dev *dev)
{
	u16 pci_command;

	pci_read_config_word(dev, PCI_COMMAND, &pci_command);
	if (pci_command & PCI_COMMAND_MASTER) {
		pci_command &= ~PCI_COMMAND_MASTER;
		pci_write_config_word(dev, PCI_COMMAND, pci_command);
	}

	pcibios_disable_device(dev);
}.
And dev->is_busmaster is set to 0 in pci_disable_device.

Signed-off-by: Cai Huoqing <cai.huoqing@linux.dev>
Acked-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>