libata-eh.c: Introduce new ata port flag for controller which lockup on read log page

Some controller lockup on a ata_read_log_page.
Add new ata port flag ATA_FLAG_NO_LOG_PAGE which can used
to blacklist a controller.

If this flag is set, any attempt to read a log page returns an error
without actually issuing the command.

Signed-off-by: Andreas Werner <andreas.werner@men.de>
Signed-off-by: Tejun Heo <tj@kernel.org>

1 files changed, 8 insertions, 0 deletions

diff --git a/drivers/ata/libata-eh.c b/drivers/ata/libata-eh.c
index cb0508af1459..961acc788f44 100644
--- a/drivers/ata/libata-eh.c
+++ b/drivers/ata/libata-eh.c
@@ -1505,12 +1505,20 @@ static const char *ata_err_string(unsigned int err_mask)
 unsigned int ata_read_log_page(struct ata_device *dev, u8 log,
                                u8 page, void *buf, unsigned int sectors)
 {
+        unsigned long ap_flags = dev->link->ap->flags;
         struct ata_taskfile tf;
         unsigned int err_mask;
         bool dma = false;
 
         DPRINTK("read log page - log 0x%x, page 0x%x\n", log, page);
 
+        /*
+         * Return error without actually issuing the command on controllers
+         * which e.g. lockup on a read log page.
+         */
+        if (ap_flags & ATA_FLAG_NO_LOG_PAGE)
+                return AC_ERR_DEV;
+
 retry:
         ata_tf_init(dev, &tf);
         if (dev->dma_mode && ata_id_has_read_log_dma_ext(dev->id) &&