wireguard-linux/drivers/mmc/core/mmc_ops.c, branch jd/unified-crypt-queue

mmc: core: Re-work the code for eMMC sanitize

2020-03-26T13:45:31Z

The error path for sanitize operations that completes with -ETIMEDOUT, is tightly coupled with the internal request handling code of the core. More precisely, mmc_wait_for_req_done() checks for specific sanitize errors. This is not only inefficient as it affects all types of requests, but also hackish. Therefore, let's improve the behaviour by moving the error path out of the mmc core. To do that, retuning needs to be held while running the sanitize operation. Moreover, to avoid exporting unnecessary symbols to the mmc block module, let's move the code into the mmc_ops.c file. While updating the actual code, let's also take the opportunity to clean up some of the mess around it. Signed-off-by: Ulf Hansson Link: https://lore.kernel.org/r/20200316152152.15122-1-ulf.hansson@linaro.org

mmc: core: Fixup support for HW busy detection for HPI commands

2020-03-24T13:35:40Z

In case the host specify a max_busy_timeout, we need to validate that the needed timeout for the HPI command conforms to that requirement. If that's not the case, let's convert from a R1B response to a R1 response, as to instruct the host to avoid HW busy detection. Additionally, when R1B is used we must also inform the host about the busy timeout for the command, so let's do that via updating cmd.busy_timeout. Finally, when R1B is used and in case the host supports HW busy detection, there should be no need for doing polling, so then skip that. Signed-off-by: Ulf Hansson Tested-by: Baolin Wang Tested-by: Ludovic Barre Reviewed-by: Ludovic Barre Link: https://lore.kernel.org/r/20200204085449.32585-12-ulf.hansson@linaro.org

mmc: core: Convert to mmc_poll_for_busy() for HPI commands

2020-03-24T13:35:40Z

Rather than open coding the polling loop in mmc_interrupt_hpi(), let's convert to use mmc_poll_for_busy(). Note that, moving to mmc_poll_for_busy() for HPI also improves the behaviour according to below. - Adds support for polling via the optional ->card_busy() host ops. - Require R1_READY_FOR_DATA to be set in the CMD13 response before exiting the polling loop. - Adds a throttling mechanism to avoid CPU hogging when polling. Signed-off-by: Ulf Hansson Tested-by: Baolin Wang Tested-by: Ludovic Barre Reviewed-by: Ludovic Barre Link: https://lore.kernel.org/r/20200204085449.32585-11-ulf.hansson@linaro.org

mmc: core: Drop redundant out-parameter to mmc_send_hpi_cmd()

2020-03-24T13:35:40Z

The 'u32 *status' is unused by the caller, so let's drop it. Signed-off-by: Ulf Hansson Tested-by: Baolin Wang Tested-by: Ludovic Barre Reviewed-by: Ludovic Barre Link: https://lore.kernel.org/r/20200204085449.32585-10-ulf.hansson@linaro.org

mmc: core: Convert to mmc_poll_for_busy() for erase/trim/discard

2020-03-24T13:35:40Z

Rather than open coding the polling loop in mmc_do_erase(), let's convert to use mmc_poll_for_busy(). To allow a slightly different error parsing during polling, compared to the __mmc_switch() case, a new in-parameter to mmc_poll_for_busy() is needed, but other than that the conversion is straight forward. Besides addressing the open coding issue, moving to mmc_poll_for_busy() for erase/trim/discard improves the behaviour according to below. - Adds support for polling via the optional ->card_busy() host ops. - Returns zero to indicate success when the final polling attempt finds the card non-busy, even if the timeout expired. - Exits the polling loop when state moves to R1_STATE_TRAN, rather than when leaving R1_STATE_PRG. - Decreases the starting range for throttling to 32-64us. Signed-off-by: Ulf Hansson Tested-by: Baolin Wang Tested-by: Ludovic Barre Reviewed-by: Ludovic Barre Link: https://lore.kernel.org/r/20200204085449.32585-9-ulf.hansson@linaro.org

mmc: core: Update CMD13 busy check for CMD6 commands

2020-03-24T13:35:39Z

Through mmc_poll_for_busy() a CMD13 may be sent to get the status of the (e)MMC card. If the state of the card is R1_STATE_PRG, the card is considered as being busy, which means we continue to poll with CMD13. This seems to be sufficient, but it's also unnecessary fragile, as it means a new command/request could potentially be sent to the card when it's in an unknown state. To try to improve the situation, but also to move towards a more consistent CMD13 polling behaviour in the mmc core, let's deploy the same policy we use for regular I/O write requests. In other words, let's check that card returns to the R1_STATE_TRAN and that the R1_READY_FOR_DATA bit is set in the CMD13 response, before exiting the polling loop. Note that, potentially this changed behaviour could lead to unnecessary waiting for the timeout to expire, if the card for some reason, moves to an unexpected error state. However, as we bail out from the polling loop when R1_SWITCH_ERROR bit is set or when the CMD13 fails, this shouldn't be an issue. Signed-off-by: Ulf Hansson Tested-by: Baolin Wang Tested-by: Ludovic Barre Reviewed-by: Ludovic Barre Link: https://lore.kernel.org/r/20200204085449.32585-8-ulf.hansson@linaro.org

mmc: core: Split up mmc_poll_for_busy()

2020-03-24T13:35:39Z

To make the code more readable, move the part that gets the busy status of the card out into a separate function, mmc_busy_status(). Then call it from mmc_poll_for_busy(). Signed-off-by: Ulf Hansson Tested-by: Baolin Wang Tested-by: Ludovic Barre Reviewed-by: Ludovic Barre Link: https://lore.kernel.org/r/20200204085449.32585-6-ulf.hansson@linaro.org

mmc: core: Drop redundant in-parameter to __mmc_switch()

2020-03-24T13:35:39Z

The use_busy_signal in-parameter is set true by all callers of __mmc_switch(), hence it's redundant so drop it. Signed-off-by: Ulf Hansson Tested-by: Baolin Wang Tested-by: Ludovic Barre Reviewed-by: Ludovic Barre Link: https://lore.kernel.org/r/20200204085449.32585-5-ulf.hansson@linaro.org

mmc: core: Extend mmc_switch_status() to rid of __mmc_switch_status()

2020-03-24T13:35:39Z

To simplify code, let's extend mmc_switch_status() to cope with needs addressed in __mmc_switch_status(). Then move all users to the updated mmc_switch_status() API and drop __mmc_switch_status() altogether. Signed-off-by: Ulf Hansson Tested-by: Baolin Wang Tested-by: Ludovic Barre Reviewed-by: Ludovic Barre Link: https://lore.kernel.org/r/20200204085449.32585-4-ulf.hansson@linaro.org

mmc: core: Drop unused define

2020-03-24T13:35:39Z

The last user of MMC_OPS_TIMEOUT_MS was recently removed, however the define stayed around. Let's remove it. Signed-off-by: Ulf Hansson Tested-by: Baolin Wang Tested-by: Ludovic Barre Reviewed-by: Ludovic Barre Link: https://lore.kernel.org/r/20200204085449.32585-3-ulf.hansson@linaro.org