Allowi() calls usb_submit_urb(pdx->pUrbCharIn, bInCallback ? GFP_ATOMIC : GFP_KERNEL) under spin_lock_irqsave(&pdx->charInLock, flags). That means it should use GFP_ATOMIC anyway. As soon as it is the only usage of bInCallback argument, the patch removes it at all.
Found by Linux Driver Verification project (linuxtesting.org). Signed-off-by: Alexey Khoroshilov <[email protected]> --- drivers/staging/ced1401/ced_ioc.c | 18 +++++++++--------- drivers/staging/ced1401/usb1401.c | 10 ++++------ drivers/staging/ced1401/usb1401.h | 2 +- 3 files changed, 14 insertions(+), 16 deletions(-) diff --git a/drivers/staging/ced1401/ced_ioc.c b/drivers/staging/ced1401/ced_ioc.c index d043471..82a333f 100644 --- a/drivers/staging/ced1401/ced_ioc.c +++ b/drivers/staging/ced1401/ced_ioc.c @@ -123,7 +123,7 @@ int SendString(DEVICE_EXTENSION * pdx, const char __user * pData, iReturn = PutChars(pdx, buffer, n); } - Allowi(pdx, false); // make sure we have input int + Allowi(pdx); // make sure we have input int mutex_unlock(&pdx->io_mutex); return iReturn; @@ -140,7 +140,7 @@ int SendChar(DEVICE_EXTENSION * pdx, char c) mutex_lock(&pdx->io_mutex); // Protect disconnect from new i/o iReturn = PutChars(pdx, &c, 1); dev_dbg(&pdx->interface->dev, "SendChar >%c< (0x%02x)", c, c); - Allowi(pdx, false); // Make sure char reads are running + Allowi(pdx); // Make sure char reads are running mutex_unlock(&pdx->io_mutex); return iReturn; } @@ -433,8 +433,8 @@ int GetChar(DEVICE_EXTENSION * pdx) dev_dbg(&pdx->interface->dev, "GetChar"); - Allowi(pdx, false); // Make sure char reads are running - SendChars(pdx); // and send any buffered chars + Allowi(pdx); // Make sure char reads are running + SendChars(pdx); // and send any buffered chars spin_lock_irq(&pdx->charInLock); if (pdx->dwNumInput > 0) // worth looking @@ -447,7 +447,7 @@ int GetChar(DEVICE_EXTENSION * pdx) iReturn = U14ERR_NOIN; // no input data to read spin_unlock_irq(&pdx->charInLock); - Allowi(pdx, false); // Make sure char reads are running + Allowi(pdx); // Make sure char reads are running mutex_unlock(&pdx->io_mutex); // Protect disconnect from new i/o return iReturn; @@ -472,7 +472,7 @@ int GetString(DEVICE_EXTENSION * pdx, char __user * pUser, int n) return -ENOMEM; mutex_lock(&pdx->io_mutex); // Protect disconnect from new i/o - Allowi(pdx, false); // Make sure char reads are running + Allowi(pdx); // Make sure char reads are running SendChars(pdx); // and send any buffered chars spin_lock_irq(&pdx->charInLock); @@ -518,7 +518,7 @@ int GetString(DEVICE_EXTENSION * pdx, char __user * pUser, int n) } else spin_unlock_irq(&pdx->charInLock); - Allowi(pdx, false); // Make sure char reads are running + Allowi(pdx); // Make sure char reads are running mutex_unlock(&pdx->io_mutex); // Protect disconnect from new i/o return iReturn; @@ -531,7 +531,7 @@ int Stat1401(DEVICE_EXTENSION * pdx) { int iReturn; mutex_lock(&pdx->io_mutex); // Protect disconnect from new i/o - Allowi(pdx, false); // make sure we allow pending chars + Allowi(pdx); // make sure we allow pending chars SendChars(pdx); // in both directions iReturn = pdx->dwNumInput; // no lock as single read mutex_unlock(&pdx->io_mutex); // Protect disconnect from new i/o @@ -550,7 +550,7 @@ int LineCount(DEVICE_EXTENSION * pdx) int iReturn = 0; // will be count of line ends mutex_lock(&pdx->io_mutex); // Protect disconnect from new i/o - Allowi(pdx, false); // Make sure char reads are running + Allowi(pdx); // Make sure char reads are running SendChars(pdx); // and send any buffered chars spin_lock_irq(&pdx->charInLock); // Get protection diff --git a/drivers/staging/ced1401/usb1401.c b/drivers/staging/ced1401/usb1401.c index a27043a..60bed3e 100644 --- a/drivers/staging/ced1401/usb1401.c +++ b/drivers/staging/ced1401/usb1401.c @@ -697,7 +697,7 @@ static void staged_callback(struct urb *pUrb) // in Allowi as if it were protected by the char lock. In any case, most systems will // not be upset by char input during DMA... sigh. Needs sorting out. if (bRestartCharInput) // may be out of date, but... - Allowi(pdx, true); // ...Allowi tests a lock too. + Allowi(pdx); // ...Allowi tests a lock too. dev_dbg(&pdx->interface->dev, "%s done", __func__); } @@ -1172,7 +1172,7 @@ static void ced_readchar_callback(struct urb *pUrb) pdx->bReadCharsPending = false; // No longer have a pending read spin_unlock(&pdx->charInLock); // already at irq level - Allowi(pdx, true); // see if we can do the next one + Allowi(pdx); // see if we can do the next one } /**************************************************************************** @@ -1182,7 +1182,7 @@ static void ced_readchar_callback(struct urb *pUrb) ** we can pick up any inward transfers. This can be called in multiple contexts ** so we use the irqsave version of the spinlock. ****************************************************************************/ -int Allowi(DEVICE_EXTENSION * pdx, bool bInCallback) +int Allowi(DEVICE_EXTENSION * pdx) { int iReturn = U14ERR_NOERROR; unsigned long flags; @@ -1211,9 +1211,7 @@ int Allowi(DEVICE_EXTENSION * pdx, bool bInCallback) pdx, pdx->bInterval); pdx->pUrbCharIn->transfer_flags |= URB_NO_TRANSFER_DMA_MAP; // short xfers are OK by default usb_anchor_urb(pdx->pUrbCharIn, &pdx->submitted); // in case we need to kill it - iReturn = - usb_submit_urb(pdx->pUrbCharIn, - bInCallback ? GFP_ATOMIC : GFP_KERNEL); + iReturn = usb_submit_urb(pdx->pUrbCharIn, GFP_ATOMIC); if (iReturn) { usb_unanchor_urb(pdx->pUrbCharIn); // remove from list of active Urbs pdx->bPipeError[nPipe] = 1; // Flag an error to be handled later diff --git a/drivers/staging/ced1401/usb1401.h b/drivers/staging/ced1401/usb1401.h index adb5fa4..8fc6958 100644 --- a/drivers/staging/ced1401/usb1401.h +++ b/drivers/staging/ced1401/usb1401.h @@ -204,7 +204,7 @@ typedef struct _DEVICE_EXTENSION /// Definitions of routimes used between compilation object files // in usb1401.c -extern int Allowi(DEVICE_EXTENSION* pdx, bool bInCallback); +extern int Allowi(DEVICE_EXTENSION* pdx); extern int SendChars(DEVICE_EXTENSION* pdx); extern void ced_draw_down(DEVICE_EXTENSION *pdx); extern int ReadWriteMem(DEVICE_EXTENSION *pdx, bool Read, unsigned short wIdent, -- 1.7.9.5 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
