The IBM partition parser requires device type specific information only available to the DASD driver to correctly register partitions. The current approach of using ioctl_by_bdev with a fake user space pointer is discouraged. Fix this by replacing IOCTL calls with direct in-kernel function calls. Suggested-by: Christoph Hellwig <hch@xxxxxx> Signed-off-by: Stefan Haberland <sth@xxxxxxxxxxxxx> Reviewed-by: Jan Hoeppner <hoeppner@xxxxxxxxxxxxx> Reviewed-by: Peter Oberparleiter <oberpar@xxxxxxxxxxxxx> --- MAINTAINERS | 1 + block/partitions/ibm.c | 24 +++++++++++++++++------ drivers/s390/block/dasd_ioctl.c | 34 +++++++++++++++++++++++++++++++++ include/linux/dasd_mod.h | 9 +++++++++ 4 files changed, 62 insertions(+), 6 deletions(-) create mode 100644 include/linux/dasd_mod.h diff --git a/MAINTAINERS b/MAINTAINERS index 1608ef8ce8d3..37f700187d74 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -14625,6 +14625,7 @@ S: Supported W: http://www.ibm.com/developerworks/linux/linux390/ F: block/partitions/ibm.c F: drivers/s390/block/dasd* +F: include/linux/dasd_mod.h S390 IOMMU (PCI) M: Gerald Schaefer <gerald.schaefer@xxxxxxxxxx> diff --git a/block/partitions/ibm.c b/block/partitions/ibm.c index 073faa6a69b8..d6e18df9c53c 100644 --- a/block/partitions/ibm.c +++ b/block/partitions/ibm.c @@ -13,10 +13,11 @@ #include <asm/ebcdic.h> #include <linux/uaccess.h> #include <asm/vtoc.h> +#include <linux/module.h> +#include <linux/dasd_mod.h> #include "check.h" - union label_t { struct vtoc_volume_label_cdl vol; struct vtoc_volume_label_ldl lnx; @@ -288,7 +289,9 @@ static int find_cms1_partitions(struct parsed_partitions *state, */ int ibm_partition(struct parsed_partitions *state) { + int (*fn)(struct gendisk *disk, dasd_information2_t *info); struct block_device *bdev = state->bdev; + struct gendisk *disk = bdev->bd_disk; int blocksize, res; loff_t i_size, offset, size; dasd_information2_t *info; @@ -299,24 +302,31 @@ int ibm_partition(struct parsed_partitions *state) union label_t *label; res = 0; + if (!disk->fops->getgeo) + goto out_exit; + fn = symbol_get(dasd_biodasdinfo); + if (!fn) + goto out_exit; blocksize = bdev_logical_block_size(bdev); if (blocksize <= 0) - goto out_exit; + goto out_symbol; i_size = i_size_read(bdev->bd_inode); if (i_size == 0) - goto out_exit; + goto out_symbol; info = kmalloc(sizeof(dasd_information2_t), GFP_KERNEL); if (info == NULL) - goto out_exit; + goto out_symbol; geo = kmalloc(sizeof(struct hd_geometry), GFP_KERNEL); if (geo == NULL) goto out_nogeo; label = kmalloc(sizeof(union label_t), GFP_KERNEL); if (label == NULL) goto out_nolab; - if (ioctl_by_bdev(bdev, HDIO_GETGEO, (unsigned long)geo) != 0) + /* set start if not filled by getgeo function e.g. virtblk */ + geo->start = get_start_sect(bdev); + if (disk->fops->getgeo(bdev, geo)) goto out_freeall; - if (ioctl_by_bdev(bdev, BIODASDINFO2, (unsigned long)info) != 0) { + if (fn(disk, info)) { kfree(info); info = NULL; } @@ -359,6 +369,8 @@ int ibm_partition(struct parsed_partitions *state) kfree(geo); out_nogeo: kfree(info); +out_symbol: + symbol_put(dasd_biodasdinfo); out_exit: return res; } diff --git a/drivers/s390/block/dasd_ioctl.c b/drivers/s390/block/dasd_ioctl.c index 9b7782395c37..777734d1b4e5 100644 --- a/drivers/s390/block/dasd_ioctl.c +++ b/drivers/s390/block/dasd_ioctl.c @@ -22,6 +22,7 @@ #include <asm/schid.h> #include <asm/cmb.h> #include <linux/uaccess.h> +#include <linux/dasd_mod.h> /* This is ugly... */ #define PRINTK_HEADER "dasd_ioctl:" @@ -664,3 +665,36 @@ int dasd_ioctl(struct block_device *bdev, fmode_t mode, dasd_put_device(base); return rc; } + + +/** + * dasd_biodasdinfo() - fill out the dasd information structure + * @disk [in]: pointer to gendisk structure that references a DASD + * @info [out]: pointer to the dasd_information2_t structure + * + * Provide access to DASD specific information. + * The gendisk structure is checked if it belongs to the DASD driver by + * comparing the gendisk->fops pointer. + * If it does not belong to the DASD driver -EINVAL is returned. + * Otherwise the provided dasd_information2_t structure is filled out. + * + * Returns: + * %0 on success and a negative error value on failure. + */ +int dasd_biodasdinfo(struct gendisk *disk, struct dasd_information2_t *info) +{ + struct dasd_device *base; + int error; + + if (disk->fops != &dasd_device_operations) + return -EINVAL; + + base = dasd_device_from_gendisk(disk); + if (!base) + return -ENODEV; + error = __dasd_ioctl_information(base->block, info); + dasd_put_device(base); + return error; +} +/* export that symbol_get in partition detection is possible */ +EXPORT_SYMBOL_GPL(dasd_biodasdinfo); diff --git a/include/linux/dasd_mod.h b/include/linux/dasd_mod.h new file mode 100644 index 000000000000..d39abad2ff6e --- /dev/null +++ b/include/linux/dasd_mod.h @@ -0,0 +1,9 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef DASD_MOD_H +#define DASD_MOD_H + +#include <asm/dasd.h> + +extern int dasd_biodasdinfo(struct gendisk *disk, dasd_information2_t *info); + +#endif -- 2.17.1
