diff options
author | Nicolas Pitre <nico@cam.org> | 2007-06-30 16:21:52 +0200 |
---|---|---|
committer | Pierre Ossman <drzeus@drzeus.cx> | 2007-09-23 20:55:13 +0200 |
commit | 2342f3323c9a76367a1d7f9a35525ee3cb3911df (patch) | |
tree | 1fdb42702137dfbe0be0c2e1c6777a0c0ddb1bcf /drivers/mmc | |
parent | sdio: defines for some standard interface types (diff) | |
download | linux-2342f3323c9a76367a1d7f9a35525ee3cb3911df.tar.xz linux-2342f3323c9a76367a1d7f9a35525ee3cb3911df.zip |
sdio: allow for mmc_claim_host to be aborted
It is sometimes necessary to give up on trying to claim the host lock,
especially if that happens in a thread that has to be stopped.
While at it, fix the description for mmc_claim_host() which was wrong.
Signed-off-by: Nicolas Pitre <npitre@mvista.com>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
Diffstat (limited to 'drivers/mmc')
-rw-r--r-- | drivers/mmc/core/core.c | 22 |
1 files changed, 16 insertions, 6 deletions
diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c index b8f27e5ade97..d1e4b0849e39 100644 --- a/drivers/mmc/core/core.c +++ b/drivers/mmc/core/core.c @@ -273,15 +273,20 @@ void mmc_set_data_timeout(struct mmc_data *data, const struct mmc_card *card) EXPORT_SYMBOL(mmc_set_data_timeout); /** - * mmc_claim_host - exclusively claim a host + * __mmc_claim_host - exclusively claim a host * @host: mmc host to claim + * @abort: whether or not the operation should be aborted * - * Claim a host for a set of operations. + * Claim a host for a set of operations. If @abort is non null and + * dereference a non-zero value then this will return prematurely with + * that non-zero value without acquiring the lock. Returns zero + * with the lock held otherwise. */ -void mmc_claim_host(struct mmc_host *host) +int __mmc_claim_host(struct mmc_host *host, atomic_t *abort) { DECLARE_WAITQUEUE(wait, current); unsigned long flags; + int stop; might_sleep(); @@ -289,19 +294,24 @@ void mmc_claim_host(struct mmc_host *host) spin_lock_irqsave(&host->lock, flags); while (1) { set_current_state(TASK_UNINTERRUPTIBLE); - if (!host->claimed) + stop = abort ? atomic_read(abort) : 0; + if (stop || !host->claimed) break; spin_unlock_irqrestore(&host->lock, flags); schedule(); spin_lock_irqsave(&host->lock, flags); } set_current_state(TASK_RUNNING); - host->claimed = 1; + if (!stop) + host->claimed = 1; + else + wake_up(&host->wq); spin_unlock_irqrestore(&host->lock, flags); remove_wait_queue(&host->wq, &wait); + return stop; } -EXPORT_SYMBOL(mmc_claim_host); +EXPORT_SYMBOL(__mmc_claim_host); /** * mmc_release_host - release a host |