lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
Open Source and information security mailing list archives
| ||
|
Date: Mon, 21 Dec 2020 18:04:13 +0530 From: rojay@...eaurora.org To: Akash Asthana <akashast@...eaurora.org> Cc: wsa@...nel.org, swboyd@...omium.org, dianders@...omium.org, saiprakash.ranjan@...eaurora.org, gregkh@...uxfoundation.org, mka@...omium.org, msavaliy@....qualcomm.com, skakit@...eaurora.org, vkaur@...eaurora.org, pyarlaga@...eaurora.org, rnayak@...eaurora.org, agross@...nel.org, bjorn.andersson@...aro.org, linux-arm-msm@...r.kernel.org, linux-i2c@...r.kernel.org, linux-kernel@...r.kernel.org, sumit.semwal@...aro.org, linux-media@...r.kernel.org Subject: Re: [RESEND PATCH V6 1/2] i2c: i2c-qcom-geni: Store DMA mapping data in geni_i2c_dev struct On 2020-12-09 18:29, Akash Asthana wrote: > Hi Roja, > > On 12/3/2020 4:01 PM, Roja Rani Yarubandi wrote: >> Store DMA mapping data in geni_i2c_dev struct to enhance DMA mapping >> data scope. For example during shutdown callback to unmap DMA mapping, >> this stored DMA mapping data can be used to call geni_se_tx_dma_unprep >> and geni_se_rx_dma_unprep functions. >> >> Add two helper functions geni_i2c_rx_msg_cleanup and >> geni_i2c_tx_msg_cleanup to unwrap the things after rx/tx FIFO/DMA >> transfers, so that the same can be used in geni_i2c_stop_xfer() >> function during shutdown callback. >> >> Signed-off-by: Roja Rani Yarubandi <rojay@...eaurora.org> >> --- >> Changes in V5: >> - As per Stephen's comments separated this patch from shutdown >> callback patch, gi2c->cur = NULL is not removed from >> geni_i2c_abort_xfer(), and made a copy of gi2c->cur and passed >> to cleanup functions. >> >> Changes in V6: >> - Added spin_lock/unlock in geni_i2c_rx_msg_cleanup() and >> geni_i2c_tx_msg_cleanup() functions. >> >> drivers/i2c/busses/i2c-qcom-geni.c | 69 >> +++++++++++++++++++++++------- >> 1 file changed, 53 insertions(+), 16 deletions(-) >> >> diff --git a/drivers/i2c/busses/i2c-qcom-geni.c >> b/drivers/i2c/busses/i2c-qcom-geni.c >> index dce75b85253c..bfbc80f65006 100644 >> --- a/drivers/i2c/busses/i2c-qcom-geni.c >> +++ b/drivers/i2c/busses/i2c-qcom-geni.c >> @@ -86,6 +86,9 @@ struct geni_i2c_dev { >> u32 clk_freq_out; >> const struct geni_i2c_clk_fld *clk_fld; >> int suspended; >> + void *dma_buf; >> + size_t xfer_len; >> + dma_addr_t dma_addr; >> }; >> struct geni_i2c_err_log { >> @@ -348,14 +351,49 @@ static void geni_i2c_tx_fsm_rst(struct >> geni_i2c_dev *gi2c) >> dev_err(gi2c->se.dev, "Timeout resetting TX_FSM\n"); >> } >> +static void geni_i2c_rx_msg_cleanup(struct geni_i2c_dev *gi2c, >> + struct i2c_msg *cur) >> +{ >> + struct geni_se *se = &gi2c->se; >> + unsigned long flags; >> + >> + spin_lock_irqsave(&gi2c->lock, flags); >> + gi2c->cur_rd = 0; >> + if (gi2c->dma_buf) { >> + if (gi2c->err) >> + geni_i2c_rx_fsm_rst(gi2c); > > Which race we are trying to avoid here by holding spinlock? > Thought that race might occur with "cur" here. > We cannot call any sleeping API by holding spinlock, > geni_i2c_rx_fsm_rst calls *wait-for-completion*, which is a sleeping > call. > Fixed this. >> + geni_se_rx_dma_unprep(se, gi2c->dma_addr, gi2c->xfer_len); >> + i2c_put_dma_safe_msg_buf(gi2c->dma_buf, cur, !gi2c->err); >> + } >> + spin_unlock_irqrestore(&gi2c->lock, flags); >> +} >> + >> +static void geni_i2c_tx_msg_cleanup(struct geni_i2c_dev *gi2c, >> + struct i2c_msg *cur) >> +{ >> + struct geni_se *se = &gi2c->se; >> + unsigned long flags; >> + >> + spin_lock_irqsave(&gi2c->lock, flags); >> + gi2c->cur_wr = 0; >> + if (gi2c->dma_buf) { >> + if (gi2c->err) >> + geni_i2c_tx_fsm_rst(gi2c); > > Same here > > Regards, > > Akash > >> + geni_se_tx_dma_unprep(se, gi2c->dma_addr, gi2c->xfer_len); >> + i2c_put_dma_safe_msg_buf(gi2c->dma_buf, cur, !gi2c->err); >> + } >> + spin_unlock_irqrestore(&gi2c->lock, flags); >> +} >> + >> static int geni_i2c_rx_one_msg(struct geni_i2c_dev *gi2c, struct >> i2c_msg *msg, >> u32 m_param) >> { >> - dma_addr_t rx_dma; >> + dma_addr_t rx_dma = 0; >> unsigned long time_left; >> void *dma_buf = NULL; >> struct geni_se *se = &gi2c->se; >> size_t len = msg->len; >> + struct i2c_msg *cur; >> if (!of_machine_is_compatible("lenovo,yoga-c630")) >> dma_buf = i2c_get_dma_safe_msg_buf(msg, 32); >> @@ -372,19 +410,18 @@ static int geni_i2c_rx_one_msg(struct >> geni_i2c_dev *gi2c, struct i2c_msg *msg, >> geni_se_select_mode(se, GENI_SE_FIFO); >> i2c_put_dma_safe_msg_buf(dma_buf, msg, false); >> dma_buf = NULL; >> + } else { >> + gi2c->xfer_len = len; >> + gi2c->dma_addr = rx_dma; >> + gi2c->dma_buf = dma_buf; >> } >> + cur = gi2c->cur; >> time_left = wait_for_completion_timeout(&gi2c->done, XFER_TIMEOUT); >> if (!time_left) >> geni_i2c_abort_xfer(gi2c); >> - gi2c->cur_rd = 0; >> - if (dma_buf) { >> - if (gi2c->err) >> - geni_i2c_rx_fsm_rst(gi2c); >> - geni_se_rx_dma_unprep(se, rx_dma, len); >> - i2c_put_dma_safe_msg_buf(dma_buf, msg, !gi2c->err); >> - } >> + geni_i2c_rx_msg_cleanup(gi2c, cur); >> return gi2c->err; >> } >> @@ -392,11 +429,12 @@ static int geni_i2c_rx_one_msg(struct >> geni_i2c_dev *gi2c, struct i2c_msg *msg, >> static int geni_i2c_tx_one_msg(struct geni_i2c_dev *gi2c, struct >> i2c_msg *msg, >> u32 m_param) >> { >> - dma_addr_t tx_dma; >> + dma_addr_t tx_dma = 0; >> unsigned long time_left; >> void *dma_buf = NULL; >> struct geni_se *se = &gi2c->se; >> size_t len = msg->len; >> + struct i2c_msg *cur; >> if (!of_machine_is_compatible("lenovo,yoga-c630")) >> dma_buf = i2c_get_dma_safe_msg_buf(msg, 32); >> @@ -413,22 +451,21 @@ static int geni_i2c_tx_one_msg(struct >> geni_i2c_dev *gi2c, struct i2c_msg *msg, >> geni_se_select_mode(se, GENI_SE_FIFO); >> i2c_put_dma_safe_msg_buf(dma_buf, msg, false); >> dma_buf = NULL; >> + } else { >> + gi2c->xfer_len = len; >> + gi2c->dma_addr = tx_dma; >> + gi2c->dma_buf = dma_buf; >> } >> if (!dma_buf) /* Get FIFO IRQ */ >> writel_relaxed(1, se->base + SE_GENI_TX_WATERMARK_REG); >> + cur = gi2c->cur; >> time_left = wait_for_completion_timeout(&gi2c->done, XFER_TIMEOUT); >> if (!time_left) >> geni_i2c_abort_xfer(gi2c); >> - gi2c->cur_wr = 0; >> - if (dma_buf) { >> - if (gi2c->err) >> - geni_i2c_tx_fsm_rst(gi2c); >> - geni_se_tx_dma_unprep(se, tx_dma, len); >> - i2c_put_dma_safe_msg_buf(dma_buf, msg, !gi2c->err); >> - } >> + geni_i2c_tx_msg_cleanup(gi2c, cur); >> return gi2c->err; >> }
Powered by blists - more mailing lists