libata: move ata_read_log_page to libata-core.c

It is core functionality, and only one of the users is in the EH code.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Tejun Heo <tj@kernel.org>

1 files changed, 64 insertions, 0 deletions

diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
index 55aaa2e..f84419f 100644
--- a/drivers/ata/libata-core.c
+++ b/drivers/ata/libata-core.c
@@ -2047,6 +2047,70 @@ retry:
 	return rc;
 }
 
+/**
+ *	ata_read_log_page - read a specific log page
+ *	@dev: target device
+ *	@log: log to read
+ *	@page: page to read
+ *	@buf: buffer to store read page
+ *	@sectors: number of sectors to read
+ *
+ *	Read log page using READ_LOG_EXT command.
+ *
+ *	LOCKING:
+ *	Kernel thread context (may sleep).
+ *
+ *	RETURNS:
+ *	0 on success, AC_ERR_* mask otherwise.
+ */
+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) &&
+	    !(dev->horkage & ATA_HORKAGE_NO_NCQ_LOG)) {
+		tf.command = ATA_CMD_READ_LOG_DMA_EXT;
+		tf.protocol = ATA_PROT_DMA;
+		dma = true;
+	} else {
+		tf.command = ATA_CMD_READ_LOG_EXT;
+		tf.protocol = ATA_PROT_PIO;
+		dma = false;
+	}
+	tf.lbal = log;
+	tf.lbam = page;
+	tf.nsect = sectors;
+	tf.hob_nsect = sectors >> 8;
+	tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_LBA48 | ATA_TFLAG_DEVICE;
+
+	err_mask = ata_exec_internal(dev, &tf, NULL, DMA_FROM_DEVICE,
+				     buf, sectors * ATA_SECT_SIZE, 0);
+
+	if (err_mask && dma) {
+		dev->horkage |= ATA_HORKAGE_NO_NCQ_LOG;
+		ata_dev_warn(dev, "READ LOG DMA EXT failed, trying unqueued\n");
+		goto retry;
+	}
+
+	DPRINTK("EXIT, err_mask=%x\n", err_mask);
+	return err_mask;
+}
+
 static int ata_do_link_spd_horkage(struct ata_device *dev)
 {
 	struct ata_link *plink = ata_dev_phys_link(dev);