[PATCH] libata: implement ata_dev_id_c_string()

ata_dev_id_c_string() reads ATA string from the specified offset of
the given IDENTIFY PAGE and puts it in the specified buffer in trimmed
and NULL-terminated form.  The caller must supply a buffer which is
one byte larger than the maximum size of the target ID string.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jgarzik@pobox.com>

diff --git a/drivers/scsi/libata-core.c b/drivers/scsi/libata-core.c
index 9ddb568267e11d8041ea9f2b1570334dbf637ef4..7e410299d67afdc867263a585a30436941e0d2ca 100644 (file)
--- a/drivers/scsi/libata-core.c
+++ b/drivers/scsi/libata-core.c
@@ -519,6 +519,34 @@ void ata_dev_id_string(const u16 *id, unsigned char *s,
        }
 }
 
+/**
+ *     ata_dev_id_c_string - Convert IDENTIFY DEVICE page into C string
+ *     @id: IDENTIFY DEVICE results we will examine
+ *     @s: string into which data is output
+ *     @ofs: offset into identify device page
+ *     @len: length of string to return. must be an odd number.
+ *
+ *     This function is identical to ata_dev_id_string except that it
+ *     trims trailing spaces and terminates the resulting string with
+ *     null.  @len must be actual maximum length (even number) + 1.
+ *
+ *     LOCKING:
+ *     caller.
+ */
+void ata_dev_id_c_string(const u16 *id, unsigned char *s,
+                        unsigned int ofs, unsigned int len)
+{
+       unsigned char *p;
+
+       WARN_ON(!(len & 1));
+
+       ata_dev_id_string(id, s, ofs, len - 1);
+
+       p = s + strnlen(s, len - 1);
+       while (p > s && p[-1] == ' ')
+               p--;
+       *p = '\0';
+}
 
 /**
  *     ata_noop_dev_select - Select device 0/1 on ATA bus
@@ -4905,6 +4933,7 @@ EXPORT_SYMBOL_GPL(ata_scsi_release);
 EXPORT_SYMBOL_GPL(ata_host_intr);
 EXPORT_SYMBOL_GPL(ata_dev_classify);
 EXPORT_SYMBOL_GPL(ata_dev_id_string);
+EXPORT_SYMBOL_GPL(ata_dev_id_c_string);
 EXPORT_SYMBOL_GPL(ata_dev_config);
 EXPORT_SYMBOL_GPL(ata_scsi_simulate);
 EXPORT_SYMBOL_GPL(ata_eh_qc_complete);

diff --git a/include/linux/libata.h b/include/linux/libata.h
index 83a1f2ead86128701edc543f9c7204c2504f05e6..0853032673b7ce2c848d720ea72c7f776471b956 100644 (file)
--- a/include/linux/libata.h
+++ b/include/linux/libata.h
@@ -540,6 +540,8 @@ extern void ata_sg_init(struct ata_queued_cmd *qc, struct scatterlist *sg,
 extern unsigned int ata_dev_classify(const struct ata_taskfile *tf);
 extern void ata_dev_id_string(const u16 *id, unsigned char *s,
                              unsigned int ofs, unsigned int len);
+extern void ata_dev_id_c_string(const u16 *id, unsigned char *s,
+                               unsigned int ofs, unsigned int len);
 extern void ata_dev_config(struct ata_port *ap, unsigned int i);
 extern void ata_bmdma_setup (struct ata_queued_cmd *qc);
 extern void ata_bmdma_start (struct ata_queued_cmd *qc);