| Message ID | 504A636F.9070106@inktank.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Reviewed-by: Josh Durgin <josh.durgin@inktank.com> On 09/07/2012 02:13 PM, Alex Elder wrote: > This defines a new function rbd_dev_probe() as a top-level > function for populating detailed information about an rbd device. > > It first checks for the existence of a format 2 rbd image id object. > If it exists, the image is assumed to be a format 2 rbd image, and > another function rbd_dev_v2() is called to finish populating > header data for that image. If it does not exist, it is assumed to > be an old (format 1) rbd image, and calls a similar function > rbd_dev_v1() to populate its header information. > > A new field, rbd_dev->format, is defined to record which version > of the rbd image format the device represents. For a valid mapped > rbd device it will have one of two values, 1 or 2. > > So far, the format 2 images are not really supported; this is > laying out the infrastructure for fleshing out that support. > > Signed-off-by: Alex Elder <elder@inktank.com> > --- > drivers/block/rbd.c | 126 > ++++++++++++++++++++++++++++++++++++++++----------- > 1 file changed, 99 insertions(+), 27 deletions(-) > > diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c > index e6b8fa6..019e695 100644 > --- a/drivers/block/rbd.c > +++ b/drivers/block/rbd.c > @@ -170,6 +170,7 @@ struct rbd_device { > int major; /* blkdev assigned major */ > struct gendisk *disk; /* blkdev's gendisk and rq */ > > + u32 image_format; /* Either 1 or 2 */ > struct rbd_options rbd_opts; > struct rbd_client *rbd_client; > > @@ -507,6 +508,11 @@ static void rbd_coll_release(struct kref *kref) > kfree(coll); > } > > +static bool rbd_image_format_valid(u32 image_format) > +{ > + return image_format == 1 || image_format == 2; > +} > + > static bool rbd_dev_ondisk_valid(struct rbd_image_header_ondisk *ondisk) > { > size_t size; > @@ -2579,6 +2585,96 @@ out: > return ret; > } > > +static int rbd_dev_v1_probe(struct rbd_device *rbd_dev) > +{ > + int ret; > + size_t size; > + > + /* Version 1 images have no id; empty string is used */ > + > + rbd_dev->image_id = kstrdup("", GFP_KERNEL); > + if (!rbd_dev->image_id) > + return -ENOMEM; > + rbd_dev->image_id_len = 0; > + > + /* Record the header object name for this rbd image. */ > + > + size = rbd_dev->image_name_len + sizeof (RBD_SUFFIX); > + rbd_dev->header_name = kmalloc(size, GFP_KERNEL); > + if (!rbd_dev->header_name) { > + ret = -ENOMEM; > + goto out_err; > + } > + sprintf(rbd_dev->header_name, "%s%s", rbd_dev->image_name, RBD_SUFFIX); > + > + /* Populate rbd image metadata */ > + > + ret = rbd_read_header(rbd_dev, &rbd_dev->header); > + if (ret < 0) > + goto out_err; > + rbd_dev->image_format = 1; > + > + dout("discovered version 1 image, header name is %s\n", > + rbd_dev->header_name); > + > + return 0; > + > +out_err: > + kfree(rbd_dev->header_name); > + rbd_dev->header_name = NULL; > + kfree(rbd_dev->image_id); > + rbd_dev->image_id = NULL; > + > + return ret; > +} > + > +static int rbd_dev_v2_probe(struct rbd_device *rbd_dev) > +{ > + size_t size; > + > + /* > + * Image id was filled in by the caller. Record the header > + * object name for this rbd image. > + */ > + size = sizeof (RBD_HEADER_PREFIX) + rbd_dev->image_id_len; > + rbd_dev->header_name = kmalloc(size, GFP_KERNEL); > + if (!rbd_dev->header_name) > + return -ENOMEM; > + sprintf(rbd_dev->header_name, "%s%s", > + RBD_HEADER_PREFIX, rbd_dev->image_id); > + rbd_dev->image_format = 2; > + > + dout("discovered version 2 image, header name is %s\n", > + rbd_dev->header_name); > + > + return -ENOTSUPP; > +} > + > +/* > + * Probe for the existence of the header object for the given rbd > + * device. For format 2 images this includes determining the image > + * id. > + */ > +static int rbd_dev_probe(struct rbd_device *rbd_dev) > +{ > + int ret; > + > + /* > + * Get the id from the image id object. If it's not a > + * format 2 image, we'll get ENOENT back, and we'll assume > + * it's a format 1 image. > + */ > + ret = rbd_dev_image_id(rbd_dev); > + if (ret == -ENOENT) > + ret = rbd_dev_v1_probe(rbd_dev); > + else if (!ret) > + ret = rbd_dev_v2_probe(rbd_dev); > + if (ret) > + dout("probe failed, returning %d\n", ret); > + > + return ret; > +} > + > static ssize_t rbd_add(struct bus_type *bus, > const char *buf, > size_t count) > @@ -2628,34 +2724,10 @@ static ssize_t rbd_add(struct bus_type *bus, > goto err_out_client; > rbd_dev->pool_id = rc; > > - rc = rbd_dev_image_id(rbd_dev); > - if (rc == -ENOENT) { > - /* Version 1 images have no id; empty string is used */ > - rbd_dev->image_id = kstrdup("", GFP_KERNEL); > - if (!rbd_dev->image_id) { > - rc = -ENOMEM; > - goto err_out_client; > - } > - rbd_dev->image_id_len = 0; > - } else { > - /* Not actually supporting format 2 yet */ > - goto err_out_client; > - } > - > - /* Create the name of the header object */ > - > - rbd_dev->header_name = kmalloc(rbd_dev->image_name_len > - + sizeof (RBD_SUFFIX), > - GFP_KERNEL); > - if (!rbd_dev->header_name) > - goto err_out_client; > - sprintf(rbd_dev->header_name, "%s%s", rbd_dev->image_name, RBD_SUFFIX); > - > - /* Get information about the image being mapped */ > - > - rc = rbd_read_header(rbd_dev, &rbd_dev->header); > - if (rc) > + rc = rbd_dev_probe(rbd_dev); > + if (rc < 0) > goto err_out_client; > + rbd_assert(rbd_image_format_valid(rbd_dev->image_format)); > > rc = rbd_dev_snaps_update(rbd_dev); > if (rc) > -- To unsubscribe from this list: send the line "unsubscribe ceph-devel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c index e6b8fa6..019e695 100644 --- a/drivers/block/rbd.c +++ b/drivers/block/rbd.c @@ -170,6 +170,7 @@ struct rbd_device { int major; /* blkdev assigned major */ struct gendisk *disk; /* blkdev's gendisk and rq */ + u32 image_format; /* Either 1 or 2 */ struct rbd_options rbd_opts; struct rbd_client *rbd_client; @@ -507,6 +508,11 @@ static void rbd_coll_release(struct kref *kref) kfree(coll); } +static bool rbd_image_format_valid(u32 image_format) +{ + return image_format == 1 || image_format == 2; +} + static bool rbd_dev_ondisk_valid(struct rbd_image_header_ondisk *ondisk) { size_t size; @@ -2579,6 +2585,96 @@ out: return ret; } +static int rbd_dev_v1_probe(struct rbd_device *rbd_dev) +{ + int ret; + size_t size; + + /* Version 1 images have no id; empty string is used */ + + rbd_dev->image_id = kstrdup("", GFP_KERNEL); + if (!rbd_dev->image_id) + return -ENOMEM; + rbd_dev->image_id_len = 0; + + /* Record the header object name for this rbd image. */ + + size = rbd_dev->image_name_len + sizeof (RBD_SUFFIX); + rbd_dev->header_name = kmalloc(size, GFP_KERNEL); + if (!rbd_dev->header_name) { + ret = -ENOMEM; + goto out_err; + } + sprintf(rbd_dev->header_name, "%s%s", rbd_dev->image_name, RBD_SUFFIX); + + /* Populate rbd image metadata */ + + ret = rbd_read_header(rbd_dev, &rbd_dev->header); + if (ret < 0) + goto out_err; + rbd_dev->image_format = 1; + + dout("discovered version 1 image, header name is %s\n", + rbd_dev->header_name); + + return 0; + +out_err: + kfree(rbd_dev->header_name); + rbd_dev->header_name = NULL; + kfree(rbd_dev->image_id); + rbd_dev->image_id = NULL; + + return ret; +} + +static int rbd_dev_v2_probe(struct rbd_device *rbd_dev) +{ + size_t size; + + /* + * Image id was filled in by the caller. Record the header + * object name for this rbd image. + */ + size = sizeof (RBD_HEADER_PREFIX) + rbd_dev->image_id_len; + rbd_dev->header_name = kmalloc(size, GFP_KERNEL); + if (!rbd_dev->header_name) + return -ENOMEM; + sprintf(rbd_dev->header_name, "%s%s", + RBD_HEADER_PREFIX, rbd_dev->image_id); + rbd_dev->image_format = 2; + + dout("discovered version 2 image, header name is %s\n", + rbd_dev->header_name); + + return -ENOTSUPP; +} + +/* + * Probe for the existence of the header object for the given rbd + * device. For format 2 images this includes determining the image + * id. + */ +static int rbd_dev_probe(struct rbd_device *rbd_dev) +{ + int ret; + + /* + * Get the id from the image id object. If it's not a + * format 2 image, we'll get ENOENT back, and we'll assume + * it's a format 1 image. + */ + ret = rbd_dev_image_id(rbd_dev); + if (ret == -ENOENT) + ret = rbd_dev_v1_probe(rbd_dev); + else if (!ret) + ret = rbd_dev_v2_probe(rbd_dev); + if (ret) + dout("probe failed, returning %d\n", ret); + + return ret; +} + static ssize_t rbd_add(struct bus_type *bus, const char *buf, size_t count) @@ -2628,34 +2724,10 @@ static ssize_t rbd_add(struct bus_type *bus, goto err_out_client; rbd_dev->pool_id = rc; - rc = rbd_dev_image_id(rbd_dev); - if (rc == -ENOENT) { - /* Version 1 images have no id; empty string is used */ - rbd_dev->image_id = kstrdup("", GFP_KERNEL); - if (!rbd_dev->image_id) { - rc = -ENOMEM; - goto err_out_client; - } - rbd_dev->image_id_len = 0; - } else { - /* Not actually supporting format 2 yet */ - goto err_out_client; - } - - /* Create the name of the header object */ - - rbd_dev->header_name = kmalloc(rbd_dev->image_name_len - + sizeof (RBD_SUFFIX), - GFP_KERNEL); - if (!rbd_dev->header_name) - goto err_out_client; - sprintf(rbd_dev->header_name, "%s%s", rbd_dev->image_name, RBD_SUFFIX); - - /* Get information about the image being mapped */ - - rc = rbd_read_header(rbd_dev, &rbd_dev->header); - if (rc) + rc = rbd_dev_probe(rbd_dev); + if (rc < 0) goto err_out_client; + rbd_assert(rbd_image_format_valid(rbd_dev->image_format)); rc = rbd_dev_snaps_update(rbd_dev); if (rc)
This defines a new function rbd_dev_probe() as a top-level function for populating detailed information about an rbd device. It first checks for the existence of a format 2 rbd image id object. If it exists, the image is assumed to be a format 2 rbd image, and another function rbd_dev_v2() is called to finish populating header data for that image. If it does not exist, it is assumed to be an old (format 1) rbd image, and calls a similar function rbd_dev_v1() to populate its header information. A new field, rbd_dev->format, is defined to record which version of the rbd image format the device represents. For a valid mapped rbd device it will have one of two values, 1 or 2. So far, the format 2 images are not really supported; this is laying out the infrastructure for fleshing out that support. Signed-off-by: Alex Elder <elder@inktank.com> --- drivers/block/rbd.c | 126 ++++++++++++++++++++++++++++++++++++++++----------- 1 file changed, 99 insertions(+), 27 deletions(-)