Messages in this thread | | | Subject | Re: [PATCH v4 05/18] nitro_enclaves: Handle PCI device command requests | From | "Paraschiv, Andra-Irina" <> | Date | Sat, 4 Jul 2020 18:05:58 +0300 |
| |
On 02/07/2020 18:19, Alexander Graf wrote: > > > On 22.06.20 22:03, Andra Paraschiv wrote: >> The Nitro Enclaves PCI device exposes a MMIO space that this driver >> uses to submit command requests and to receive command replies e.g. for >> enclave creation / termination or setting enclave resources. >> >> Add logic for handling PCI device command requests based on the given >> command type. >> >> Register an MSI-X interrupt vector for command reply notifications to >> handle this type of communication events. >> >> Signed-off-by: Alexandru-Catalin Vasile <lexnv@amazon.com> >> Signed-off-by: Andra Paraschiv <andraprs@amazon.com> >> >> Fix issue reported in: >> https://lore.kernel.org/lkml/202004231644.xTmN4Z1z%25lkp@intel.com/ >> >> Reported-by: kbuild test robot <lkp@intel.com> >> Signed-off-by: Andra Paraschiv <andraprs@amazon.com> >> --- >> Changelog >> >> v3 -> v4 >> >> * Use dev_err instead of custom NE log pattern. >> * Return IRQ_NONE when interrupts are not handled. >> >> v2 -> v3 >> >> * Remove the WARN_ON calls. >> * Update static calls sanity checks. >> * Remove "ratelimited" from the logs that are not in the ioctl call >> paths. >> >> v1 -> v2 >> >> * Add log pattern for NE. >> * Remove the BUG_ON calls. >> * Update goto labels to match their purpose. >> * Add fix for kbuild report. >> --- >> drivers/virt/nitro_enclaves/ne_pci_dev.c | 232 +++++++++++++++++++++++ >> 1 file changed, 232 insertions(+) >> >> diff --git a/drivers/virt/nitro_enclaves/ne_pci_dev.c >> b/drivers/virt/nitro_enclaves/ne_pci_dev.c >> index 235fa3ecbee2..c24230cfe7c0 100644 >> --- a/drivers/virt/nitro_enclaves/ne_pci_dev.c >> +++ b/drivers/virt/nitro_enclaves/ne_pci_dev.c >> @@ -27,6 +27,218 @@ static const struct pci_device_id ne_pci_ids[] = { >> MODULE_DEVICE_TABLE(pci, ne_pci_ids); >> +/** >> + * ne_submit_request - Submit command request to the PCI device >> based on the >> + * command type. >> + * >> + * This function gets called with the ne_pci_dev mutex held. >> + * >> + * @pdev: PCI device to send the command to. >> + * @cmd_type: command type of the request sent to the PCI device. >> + * @cmd_request: command request payload. >> + * @cmd_request_size: size of the command request payload. >> + * >> + * @returns: 0 on success, negative return value on failure. >> + */ >> +static int ne_submit_request(struct pci_dev *pdev, >> + enum ne_pci_dev_cmd_type cmd_type, >> + void *cmd_request, size_t cmd_request_size) >> +{ >> + struct ne_pci_dev *ne_pci_dev = pci_get_drvdata(pdev); >> + >> + if (!ne_pci_dev || !ne_pci_dev->iomem_base) >> + return -EINVAL; > > How can this ever happen?
Removed this one and the next checks in v5 of the patch series.
Thanks, Andra
> >> + >> + memcpy_toio(ne_pci_dev->iomem_base + NE_SEND_DATA, cmd_request, >> + cmd_request_size); >> + >> + iowrite32(cmd_type, ne_pci_dev->iomem_base + NE_COMMAND); >> + >> + return 0; >> +} >> + >> +/** >> + * ne_retrieve_reply - Retrieve reply from the PCI device. >> + * >> + * This function gets called with the ne_pci_dev mutex held. >> + * >> + * @pdev: PCI device to receive the reply from. >> + * @cmd_reply: command reply payload. >> + * @cmd_reply_size: size of the command reply payload. >> + * >> + * @returns: 0 on success, negative return value on failure. >> + */ >> +static int ne_retrieve_reply(struct pci_dev *pdev, >> + struct ne_pci_dev_cmd_reply *cmd_reply, >> + size_t cmd_reply_size) >> +{ >> + struct ne_pci_dev *ne_pci_dev = pci_get_drvdata(pdev); >> + >> + if (!ne_pci_dev || !ne_pci_dev->iomem_base) >> + return -EINVAL; > > Same. > >> + >> + memcpy_fromio(cmd_reply, ne_pci_dev->iomem_base + NE_RECV_DATA, >> + cmd_reply_size); >> + >> + return 0; >> +} >> + >> +/** >> + * ne_wait_for_reply - Wait for a reply of a PCI command. >> + * >> + * This function gets called with the ne_pci_dev mutex held. >> + * >> + * @pdev: PCI device for which a reply is waited. >> + * >> + * @returns: 0 on success, negative return value on failure. >> + */ >> +static int ne_wait_for_reply(struct pci_dev *pdev) >> +{ >> + struct ne_pci_dev *ne_pci_dev = pci_get_drvdata(pdev); >> + int rc = -EINVAL; > > Unused assignment? > >> + >> + if (!ne_pci_dev) >> + return -EINVAL; > > Same. > >> + >> + /* >> + * TODO: Update to _interruptible and handle interrupted wait event >> + * e.g. -ERESTARTSYS, incoming signals + add / update timeout. >> + */ >> + rc = wait_event_timeout(ne_pci_dev->cmd_reply_wait_q, >> + atomic_read(&ne_pci_dev->cmd_reply_avail) != 0, >> + msecs_to_jiffies(NE_DEFAULT_TIMEOUT_MSECS)); >> + if (!rc) >> + return -ETIMEDOUT; >> + >> + return 0; >> +} >> + >> +int ne_do_request(struct pci_dev *pdev, enum ne_pci_dev_cmd_type >> cmd_type, >> + void *cmd_request, size_t cmd_request_size, >> + struct ne_pci_dev_cmd_reply *cmd_reply, size_t >> cmd_reply_size) >> +{ >> + struct ne_pci_dev *ne_pci_dev = NULL; >> + int rc = -EINVAL; >> + >> + if (!pdev) >> + return -ENODEV; > > When can this happen? > >> + >> + ne_pci_dev = pci_get_drvdata(pdev); >> + if (!ne_pci_dev || !ne_pci_dev->iomem_base) >> + return -EINVAL; > > Same > >> + >> + if (cmd_type <= INVALID_CMD || cmd_type >= MAX_CMD) { >> + dev_err_ratelimited(&pdev->dev, "Invalid cmd type=%u\n", >> + cmd_type); >> + >> + return -EINVAL; >> + } >> + >> + if (!cmd_request) { >> + dev_err_ratelimited(&pdev->dev, "Null cmd request\n"); >> + >> + return -EINVAL; >> + } >> + >> + if (cmd_request_size > NE_SEND_DATA_SIZE) { >> + dev_err_ratelimited(&pdev->dev, >> + "Invalid req size=%zu for cmd type=%u\n", >> + cmd_request_size, cmd_type); >> + >> + return -EINVAL; >> + } >> + >> + if (!cmd_reply) { >> + dev_err_ratelimited(&pdev->dev, "Null cmd reply\n"); >> + >> + return -EINVAL; >> + } >> + >> + if (cmd_reply_size > NE_RECV_DATA_SIZE) { >> + dev_err_ratelimited(&pdev->dev, "Invalid reply size=%zu\n", >> + cmd_reply_size); >> + >> + return -EINVAL; >> + } >> + >> + /* >> + * Use this mutex so that the PCI device handles one command >> request at >> + * a time. >> + */ >> + mutex_lock(&ne_pci_dev->pci_dev_mutex); >> + >> + atomic_set(&ne_pci_dev->cmd_reply_avail, 0); >> + >> + rc = ne_submit_request(pdev, cmd_type, cmd_request, >> cmd_request_size); >> + if (rc < 0) { >> + dev_err_ratelimited(&pdev->dev, >> + "Error in submit request [rc=%d]\n", rc); >> + >> + goto unlock_mutex; >> + } >> + >> + rc = ne_wait_for_reply(pdev); >> + if (rc < 0) { >> + dev_err_ratelimited(&pdev->dev, >> + "Error in wait for reply [rc=%d]\n", rc); >> + >> + goto unlock_mutex; >> + } >> + >> + rc = ne_retrieve_reply(pdev, cmd_reply, cmd_reply_size); >> + if (rc < 0) { >> + dev_err_ratelimited(&pdev->dev, >> + "Error in retrieve reply [rc=%d]\n", rc); >> + >> + goto unlock_mutex; >> + } >> + >> + atomic_set(&ne_pci_dev->cmd_reply_avail, 0); >> + >> + if (cmd_reply->rc < 0) { >> + dev_err_ratelimited(&pdev->dev, >> + "Error in cmd process logic [rc=%d]\n", >> + cmd_reply->rc); >> + >> + rc = cmd_reply->rc; >> + >> + goto unlock_mutex; >> + } >> + >> + mutex_unlock(&ne_pci_dev->pci_dev_mutex); >> + >> + return 0; > > Can you just set rc to 0 and fall through?
Done.
> >> + >> +unlock_mutex: >> + mutex_unlock(&ne_pci_dev->pci_dev_mutex); >> + >> + return rc; >> +} >> + >> +/** >> + * ne_reply_handler - Interrupt handler for retrieving a reply matching >> + * a request sent to the PCI device for enclave lifetime management. >> + * >> + * @irq: received interrupt for a reply sent by the PCI device. >> + * @args: PCI device private data structure. >> + * >> + * @returns: IRQ_HANDLED on handled interrupt, IRQ_NONE otherwise. >> + */ >> +static irqreturn_t ne_reply_handler(int irq, void *args) >> +{ >> + struct ne_pci_dev *ne_pci_dev = (struct ne_pci_dev *)args; >> + >> + if (!ne_pci_dev) >> + return IRQ_NONE; > > How can this ever happen? > > > Alex > >> + >> + atomic_set(&ne_pci_dev->cmd_reply_avail, 1); >> + >> + /* TODO: Update to _interruptible. */ >> + wake_up(&ne_pci_dev->cmd_reply_wait_q); >> + >> + return IRQ_HANDLED; >> +} >> + >> /** >> * ne_setup_msix - Setup MSI-X vectors for the PCI device. >> * >> @@ -59,7 +271,25 @@ static int ne_setup_msix(struct pci_dev *pdev) >> return rc; >> } >> + /* >> + * This IRQ gets triggered every time the PCI device responds to a >> + * command request. The reply is then retrieved, reading from >> the MMIO >> + * space of the PCI device. >> + */ >> + rc = request_irq(pci_irq_vector(pdev, NE_VEC_REPLY), >> + ne_reply_handler, 0, "enclave_cmd", ne_pci_dev); >> + if (rc < 0) { >> + dev_err(&pdev->dev, "Error in request irq reply [rc=%d]\n", >> rc); >> + >> + goto free_irq_vectors; >> + } >> + >> return 0; >> + >> +free_irq_vectors: >> + pci_free_irq_vectors(pdev); >> + >> + return rc; >> } >> /** >> @@ -74,6 +304,8 @@ static void ne_teardown_msix(struct pci_dev *pdev) >> if (!ne_pci_dev) >> return; >> + free_irq(pci_irq_vector(pdev, NE_VEC_REPLY), ne_pci_dev); >> + >> pci_free_irq_vectors(pdev); >> } >>
Amazon Development Center (Romania) S.R.L. registered office: 27A Sf. Lazar Street, UBC5, floor 2, Iasi, Iasi County, 700045, Romania. Registered in Romania. Registration number J22/2621/2005.
| |