Adrian Hunter wrote:
On 03/02/12 11:33, Ulf Hansson wrote:
To prevent I/O as soon as possible at card removal, a new
detect work is re-scheduled without a delay to let a rescan
remove the card device as soon a possible.
Additionally, MMC_CAP2_DETECT_ON_ERR can now be used to handle
"slowly" removed cards that a scheduled detect work did not
detect as removed. To prevent further I/O requests for these
lingering removed cards, check if card has been removed and then
schedule a detect work to properly remove it.
Signed-off-by: Ulf Hansson <ulf.hansson@xxxxxxxxxxxxxx>
---
Changes in v3:
- Check for card is NULL and minor code simplifications.
Changes in v2:
- Updated according to review comments.
- Merging two patches for this feature into one.
---
drivers/mmc/core/core.c | 24 +++++++++++++++++++++---
include/linux/mmc/host.h | 1 +
2 files changed, 22 insertions(+), 3 deletions(-)
diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c
index bec0bf2..9645e8c 100644
--- a/drivers/mmc/core/core.c
+++ b/drivers/mmc/core/core.c
@@ -2077,18 +2077,36 @@ int _mmc_detect_card_removed(struct mmc_host *host)
int mmc_detect_card_removed(struct mmc_host *host)
{
struct mmc_card *card = host->card;
+ int ret;
WARN_ON(!host->claimed);
+
+ if (!card)
+ return 1;
+
+ ret = mmc_card_removed(card);
/*
* The card will be considered unchanged unless we have been asked to
* detect a change or host requires polling to provide card detection.
*/
- if (card && !host->detect_change && !(host->caps & MMC_CAP_NEEDS_POLL))
- return mmc_card_removed(card);
+ if (!host->detect_change && !(host->caps & MMC_CAP_NEEDS_POLL) &&
+ !(host->caps2 & MMC_CAP2_DETECT_ON_ERR))
+ return ret;
host->detect_change = 0;
+ if (!ret) {
+ ret = _mmc_detect_card_removed(host);
+ if (ret) {
Please make this
if (ret && (host->caps2 & MMC_CAP2_DETECT_ON_ERR))
because if rescan is already running this will needlessly queue
another one.
It wont queue another one. It will cancel a work which likely has been
scheduled to be executed within several ms later. Then it will
re-schedule a new one without any delay since there is no need to wait,
when we already know that the card has been removed.
+ /*
+ * Schedule a detect work as soon as possible to let a
+ * rescan handle the card removal.
+ */
+ cancel_delayed_work(&host->detect);
+ mmc_detect_change(host, 0);
+ }
+ }
- return _mmc_detect_card_removed(host);
+ return ret;
}
EXPORT_SYMBOL(mmc_detect_card_removed);
diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h
index dd13e05..368a2b9 100644
--- a/include/linux/mmc/host.h
+++ b/include/linux/mmc/host.h
@@ -257,6 +257,7 @@ struct mmc_host {
#define MMC_CAP2_HS200_1_2V_SDR (1 << 6) /* can support */
#define MMC_CAP2_HS200 (MMC_CAP2_HS200_1_8V_SDR | \
MMC_CAP2_HS200_1_2V_SDR)
+#define MMC_CAP2_DETECT_ON_ERR (1 << 7) /* On I/O err check card removal */
mmc_pm_flag_t pm_caps; /* supported pm features */
unsigned int power_notify_type;
--
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