8 files changed, 389 insertions, 159 deletions

diff --git a/block/Makefile b/block/Makefile
index 045f7b62e4bb..208000b0750d 100644
--- a/block/Makefile
+++ b/block/Makefile
@@ -4,7 +4,8 @@
 
 obj-$(CONFIG_BLOCK) := elevator.o blk-core.o blk-tag.o blk-sysfs.o \
                         blk-barrier.o blk-settings.o blk-ioc.o blk-map.o \
-                        blk-exec.o blk-merge.o ioctl.o genhd.o scsi_ioctl.o
+                        blk-exec.o blk-merge.o ioctl.o genhd.o scsi_ioctl.o \
+                        cmd-filter.o
 
 obj-$(CONFIG_BLK_DEV_BSG)       += bsg.o
 obj-$(CONFIG_IOSCHED_NOOP)      += noop-iosched.o
diff --git a/block/bsg.c b/block/bsg.c
index f0b7cd343216..439940c3a1ff 100644
--- a/block/bsg.c
+++ b/block/bsg.c
@@ -44,11 +44,12 @@ struct bsg_device {
         char name[BUS_ID_SIZE];
         int max_queue;
         unsigned long flags;
+        struct blk_scsi_cmd_filter *cmd_filter;
+        mode_t *f_mode;
 };
 
 enum {
         BSG_F_BLOCK             = 1,
-        BSG_F_WRITE_PERM        = 2,
 };
 
 #define BSG_DEFAULT_CMDS        64
@@ -172,7 +173,7 @@ unlock:
 }
 
 static int blk_fill_sgv4_hdr_rq(struct request_queue *q, struct request *rq,
-                                struct sg_io_v4 *hdr, int has_write_perm)
+                                struct sg_io_v4 *hdr, struct bsg_device *bd)
 {
         if (hdr->request_len > BLK_MAX_CDB) {
                 rq->cmd = kzalloc(hdr->request_len, GFP_KERNEL);
@@ -185,7 +186,8 @@ static int blk_fill_sgv4_hdr_rq(struct request_queue *q, struct request *rq,
                 return -EFAULT;
 
         if (hdr->subprotocol == BSG_SUB_PROTOCOL_SCSI_CMD) {
-                if (blk_verify_command(rq->cmd, has_write_perm))
+                if (blk_cmd_filter_verify_command(bd->cmd_filter, rq->cmd,
+                                                 bd->f_mode))
                         return -EPERM;
         } else if (!capable(CAP_SYS_RAWIO))
                 return -EPERM;
@@ -263,8 +265,7 @@ bsg_map_hdr(struct bsg_device *bd, struct sg_io_v4 *hdr)
         rq = blk_get_request(q, rw, GFP_KERNEL);
         if (!rq)
                 return ERR_PTR(-ENOMEM);
-        ret = blk_fill_sgv4_hdr_rq(q, rq, hdr, test_bit(BSG_F_WRITE_PERM,
-                                                       &bd->flags));
+        ret = blk_fill_sgv4_hdr_rq(q, rq, hdr, bd);
         if (ret)
                 goto out;
 
@@ -566,12 +567,23 @@ static inline void bsg_set_block(struct bsg_device *bd, struct file *file)
                 set_bit(BSG_F_BLOCK, &bd->flags);
 }
 
-static inline void bsg_set_write_perm(struct bsg_device *bd, struct file *file)
+static void bsg_set_cmd_filter(struct bsg_device *bd,
+                           struct file *file)
 {
-        if (file->f_mode & FMODE_WRITE)
-                set_bit(BSG_F_WRITE_PERM, &bd->flags);
-        else
-                clear_bit(BSG_F_WRITE_PERM, &bd->flags);
+        struct inode *inode;
+        struct gendisk *disk;
+
+        if (!file)
+                return;
+
+        inode = file->f_dentry->d_inode;
+        if (!inode)
+                return;
+
+        disk = inode->i_bdev->bd_disk;
+
+        bd->cmd_filter = &disk->cmd_filter;
+        bd->f_mode = &file->f_mode;
 }
 
 /*
@@ -595,6 +607,8 @@ bsg_read(struct file *file, char __user *buf, size_t count, loff_t *ppos)
         dprintk("%s: read %Zd bytes\n", bd->name, count);
 
         bsg_set_block(bd, file);
+        bsg_set_cmd_filter(bd, file);
+
         bytes_read = 0;
         ret = __bsg_read(buf, count, bd, NULL, &bytes_read);
         *ppos = bytes_read;
@@ -668,7 +682,7 @@ bsg_write(struct file *file, const char __user *buf, size_t count, loff_t *ppos)
         dprintk("%s: write %Zd bytes\n", bd->name, count);
 
         bsg_set_block(bd, file);
-        bsg_set_write_perm(bd, file);
+        bsg_set_cmd_filter(bd, file);
 
         bytes_written = 0;
         ret = __bsg_write(bd, buf, count, &bytes_written);
@@ -771,7 +785,9 @@ static struct bsg_device *bsg_add_device(struct inode *inode,
         }
 
         bd->queue = rq;
+
         bsg_set_block(bd, file);
+        bsg_set_cmd_filter(bd, file);
 
         atomic_set(&bd->ref_count, 1);
         mutex_lock(&bsg_mutex);
diff --git a/block/cmd-filter.c b/block/cmd-filter.c
new file mode 100644
index 000000000000..35e327ceaa97
--- /dev/null
+++ b/block/cmd-filter.c
@@ -0,0 +1,325 @@
+/*
+ * Copyright 2004 Peter M. Jones <pjones@redhat.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public Licens
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-
+ *
+ */
+
+#include <linux/list.h>
+#include <linux/genhd.h>
+#include <linux/spinlock.h>
+#include <linux/parser.h>
+#include <linux/capability.h>
+#include <linux/bitops.h>
+
+#include <scsi/scsi.h>
+#include <linux/cdrom.h>
+
+int blk_cmd_filter_verify_command(struct blk_scsi_cmd_filter *filter,
+                                  unsigned char *cmd, mode_t *f_mode)
+{
+        /* root can do any command. */
+        if (capable(CAP_SYS_RAWIO))
+                return 0;
+
+        /* if there's no filter set, assume we're filtering everything out */
+        if (!filter)
+                return -EPERM;
+
+        /* Anybody who can open the device can do a read-safe command */
+        if (test_bit(cmd[0], filter->read_ok))
+                return 0;
+
+        /* Write-safe commands require a writable open */
+        if (test_bit(cmd[0], filter->write_ok) && (*f_mode & FMODE_WRITE))
+                return 0;
+
+        return -EPERM;
+}
+EXPORT_SYMBOL(blk_cmd_filter_verify_command);
+
+int blk_verify_command(struct file *file, unsigned char *cmd)
+{
+        struct gendisk *disk;
+        struct inode *inode;
+
+        if (!file)
+                return -EINVAL;
+
+        inode = file->f_dentry->d_inode;
+        if (!inode)
+                return -EINVAL;
+
+        disk = inode->i_bdev->bd_disk;
+
+        return blk_cmd_filter_verify_command(&disk->cmd_filter,
+                                                 cmd, &file->f_mode);
+}
+EXPORT_SYMBOL(blk_verify_command);
+
+/* and now, the sysfs stuff */
+static ssize_t rcf_cmds_show(struct blk_scsi_cmd_filter *filter, char *page,
+                             int rw)
+{
+        char *npage = page;
+        unsigned long *okbits;
+        int i;
+
+        if (rw == READ)
+                okbits = filter->read_ok;
+        else
+                okbits = filter->write_ok;
+
+        for (i = 0; i < BLK_SCSI_MAX_CMDS; i++) {
+                if (test_bit(i, okbits)) {
+                        sprintf(npage, "%02x", i);
+                        npage += 2;
+                        if (i < BLK_SCSI_MAX_CMDS - 1)
+                                sprintf(npage++, " ");
+                }
+        }
+
+        if (npage != page)
+                npage += sprintf(npage, "\n");
+
+        return npage - page;
+}
+
+static ssize_t rcf_readcmds_show(struct blk_scsi_cmd_filter *filter, char *page)
+{
+        return rcf_cmds_show(filter, page, READ);
+}
+
+static ssize_t rcf_writecmds_show(struct blk_scsi_cmd_filter *filter,
+                                 char *page)
+{
+        return rcf_cmds_show(filter, page, WRITE);
+}
+
+static ssize_t rcf_cmds_store(struct blk_scsi_cmd_filter *filter,
+                              const char *page, size_t count, int rw)
+{
+        ssize_t ret = 0;
+        unsigned long okbits[BLK_SCSI_CMD_PER_LONG], *target_okbits;
+        int cmd, status, len;
+        substring_t ss;
+
+        memset(&okbits, 0, sizeof(okbits));
+
+        for (len = strlen(page); len > 0; len -= 3) {
+                if (len < 2)
+                        break;
+                ss.from = (char *) page + ret;
+                ss.to = (char *) page + ret + 2;
+                ret += 3;
+                status = match_hex(&ss, &cmd);
+                /* either of these cases means invalid input, so do nothing. */
+                if (status || cmd >= BLK_SCSI_MAX_CMDS)
+                        return -EINVAL;
+
+                __set_bit(cmd, okbits);
+        }
+
+        if (rw == READ)
+                target_okbits = filter->read_ok;
+        else
+                target_okbits = filter->write_ok;
+
+        memmove(target_okbits, okbits, sizeof(okbits));
+        return count;
+}
+
+static ssize_t rcf_readcmds_store(struct blk_scsi_cmd_filter *filter,
+                                  const char *page, size_t count)
+{
+        return rcf_cmds_store(filter, page, count, READ);
+}
+
+static ssize_t rcf_writecmds_store(struct blk_scsi_cmd_filter *filter,
+                                   const char *page, size_t count)
+{
+        return rcf_cmds_store(filter, page, count, WRITE);
+}
+
+struct rcf_sysfs_entry {
+        struct attribute attr;
+        ssize_t (*show)(struct blk_scsi_cmd_filter *, char *);
+        ssize_t (*store)(struct blk_scsi_cmd_filter *, const char *, size_t);
+};
+
+static struct rcf_sysfs_entry rcf_readcmds_entry = {
+        .attr = { .name = "read_table", .mode = S_IRUGO | S_IWUSR },
+        .show = rcf_readcmds_show,
+        .store = rcf_readcmds_store,
+};
+
+static struct rcf_sysfs_entry rcf_writecmds_entry = {
+        .attr = {.name = "write_table", .mode = S_IRUGO | S_IWUSR },
+        .show = rcf_writecmds_show,
+        .store = rcf_writecmds_store,
+};
+
+static struct attribute *default_attrs[] = {
+        &rcf_readcmds_entry.attr,
+        &rcf_writecmds_entry.attr,
+        NULL,
+};
+
+#define to_rcf(atr) container_of((atr), struct rcf_sysfs_entry, attr)
+
+static ssize_t
+rcf_attr_show(struct kobject *kobj, struct attribute *attr, char *page)
+{
+        struct rcf_sysfs_entry *entry = to_rcf(attr);
+        struct blk_scsi_cmd_filter *filter;
+
+        filter = container_of(kobj, struct blk_scsi_cmd_filter, kobj);
+        if (entry->show)
+                return entry->show(filter, page);
+
+        return 0;
+}
+
+static ssize_t
+rcf_attr_store(struct kobject *kobj, struct attribute *attr,
+                        const char *page, size_t length)
+{
+        struct rcf_sysfs_entry *entry = to_rcf(attr);
+        struct blk_scsi_cmd_filter *filter;
+
+        if (!capable(CAP_SYS_RAWIO))
+                return -EPERM;
+
+        if (!entry->store)
+                return -EINVAL;
+
+        filter = container_of(kobj, struct blk_scsi_cmd_filter, kobj);
+        return entry->store(filter, page, length);
+}
+
+static struct sysfs_ops rcf_sysfs_ops = {
+        .show = rcf_attr_show,
+        .store = rcf_attr_store,
+};
+
+static struct kobj_type rcf_ktype = {
+        .sysfs_ops = &rcf_sysfs_ops,
+        .default_attrs = default_attrs,
+};
+
+static void rcf_set_defaults(struct blk_scsi_cmd_filter *filter)
+{
+        /* Basic read-only commands */
+        __set_bit(TEST_UNIT_READY, filter->read_ok);
+        __set_bit(REQUEST_SENSE, filter->read_ok);
+        __set_bit(READ_6, filter->read_ok);
+        __set_bit(READ_10, filter->read_ok);
+        __set_bit(READ_12, filter->read_ok);
+        __set_bit(READ_16, filter->read_ok);
+        __set_bit(READ_BUFFER, filter->read_ok);
+        __set_bit(READ_DEFECT_DATA, filter->read_ok);
+        __set_bit(READ_LONG, filter->read_ok);
+        __set_bit(INQUIRY, filter->read_ok);
+        __set_bit(MODE_SENSE, filter->read_ok);
+        __set_bit(MODE_SENSE_10, filter->read_ok);
+        __set_bit(LOG_SENSE, filter->read_ok);
+        __set_bit(START_STOP, filter->read_ok);
+        __set_bit(GPCMD_VERIFY_10, filter->read_ok);
+        __set_bit(VERIFY_16, filter->read_ok);
+        __set_bit(GPCMD_READ_BUFFER_CAPACITY, filter->read_ok);
+
+        /* Audio CD commands */
+        __set_bit(GPCMD_PLAY_CD, filter->read_ok);
+        __set_bit(GPCMD_PLAY_AUDIO_10, filter->read_ok);
+        __set_bit(GPCMD_PLAY_AUDIO_MSF, filter->read_ok);
+        __set_bit(GPCMD_PLAY_AUDIO_TI, filter->read_ok);
+        __set_bit(GPCMD_PAUSE_RESUME, filter->read_ok);
+
+        /* CD/DVD data reading */
+        __set_bit(GPCMD_READ_CD, filter->read_ok);
+        __set_bit(GPCMD_READ_CD_MSF, filter->read_ok);
+        __set_bit(GPCMD_READ_DISC_INFO, filter->read_ok);
+        __set_bit(GPCMD_READ_CDVD_CAPACITY, filter->read_ok);
+        __set_bit(GPCMD_READ_DVD_STRUCTURE, filter->read_ok);
+        __set_bit(GPCMD_READ_HEADER, filter->read_ok);
+        __set_bit(GPCMD_READ_TRACK_RZONE_INFO, filter->read_ok);
+        __set_bit(GPCMD_READ_SUBCHANNEL, filter->read_ok);
+        __set_bit(GPCMD_READ_TOC_PMA_ATIP, filter->read_ok);
+        __set_bit(GPCMD_REPORT_KEY, filter->read_ok);
+        __set_bit(GPCMD_SCAN, filter->read_ok);
+        __set_bit(GPCMD_GET_CONFIGURATION, filter->read_ok);
+        __set_bit(GPCMD_READ_FORMAT_CAPACITIES, filter->read_ok);
+        __set_bit(GPCMD_GET_EVENT_STATUS_NOTIFICATION, filter->read_ok);
+        __set_bit(GPCMD_GET_PERFORMANCE, filter->read_ok);
+        __set_bit(GPCMD_SEEK, filter->read_ok);
+        __set_bit(GPCMD_STOP_PLAY_SCAN, filter->read_ok);
+
+        /* Basic writing commands */
+        __set_bit(WRITE_6, filter->write_ok);
+        __set_bit(WRITE_10, filter->write_ok);
+        __set_bit(WRITE_VERIFY, filter->write_ok);
+        __set_bit(WRITE_12, filter->write_ok);
+        __set_bit(WRITE_VERIFY_12, filter->write_ok);
+        __set_bit(WRITE_16, filter->write_ok);
+        __set_bit(WRITE_LONG, filter->write_ok);
+        __set_bit(WRITE_LONG_2, filter->write_ok);
+        __set_bit(ERASE, filter->write_ok);
+        __set_bit(GPCMD_MODE_SELECT_10, filter->write_ok);
+        __set_bit(MODE_SELECT, filter->write_ok);
+        __set_bit(LOG_SELECT, filter->write_ok);
+        __set_bit(GPCMD_BLANK, filter->write_ok);
+        __set_bit(GPCMD_CLOSE_TRACK, filter->write_ok);
+        __set_bit(GPCMD_FLUSH_CACHE, filter->write_ok);
+        __set_bit(GPCMD_FORMAT_UNIT, filter->write_ok);
+        __set_bit(GPCMD_REPAIR_RZONE_TRACK, filter->write_ok);
+        __set_bit(GPCMD_RESERVE_RZONE_TRACK, filter->write_ok);
+        __set_bit(GPCMD_SEND_DVD_STRUCTURE, filter->write_ok);
+        __set_bit(GPCMD_SEND_EVENT, filter->write_ok);
+        __set_bit(GPCMD_SEND_KEY, filter->write_ok);
+        __set_bit(GPCMD_SEND_OPC, filter->write_ok);
+        __set_bit(GPCMD_SEND_CUE_SHEET, filter->write_ok);
+        __set_bit(GPCMD_SET_SPEED, filter->write_ok);
+        __set_bit(GPCMD_PREVENT_ALLOW_MEDIUM_REMOVAL, filter->write_ok);
+        __set_bit(GPCMD_LOAD_UNLOAD, filter->write_ok);
+        __set_bit(GPCMD_SET_STREAMING, filter->write_ok);
+}
+
+int blk_register_filter(struct gendisk *disk)
+{
+        int ret;
+        struct blk_scsi_cmd_filter *filter = &disk->cmd_filter;
+        struct kobject *parent = kobject_get(disk->holder_dir->parent);
+
+        if (!parent)
+                return -ENODEV;
+
+        ret = kobject_init_and_add(&filter->kobj, &rcf_ktype, parent,
+                                 "%s", "cmd_filter");
+
+        if (ret < 0)
+                return ret;
+
+        rcf_set_defaults(filter);
+        return 0;
+}
+
+void blk_unregister_filter(struct gendisk *disk)
+{
+        struct blk_scsi_cmd_filter *filter = &disk->cmd_filter;
+
+        kobject_put(&filter->kobj);
+        kobject_put(disk->holder_dir->parent);
+}
+
diff --git a/block/genhd.c b/block/genhd.c
index 43e468ee5993..9074f384b097 100644
--- a/block/genhd.c
+++ b/block/genhd.c
@@ -189,6 +189,7 @@ void add_disk(struct gendisk *disk)
                             disk->minors, NULL, exact_match, exact_lock, disk);
         register_disk(disk);
         blk_register_queue(disk);
+        blk_register_filter(disk);
 
         bdi = &disk->queue->backing_dev_info;
         bdi_register_dev(bdi, MKDEV(disk->major, disk->first_minor));
@@ -200,6 +201,7 @@ EXPORT_SYMBOL(del_gendisk);	/* in partitions/check.c */
 
 void unlink_gendisk(struct gendisk *disk)
 {
+        blk_unregister_filter(disk);
         sysfs_remove_link(&disk->dev.kobj, "bdi");
         bdi_unregister(&disk->queue->backing_dev_info);
         blk_unregister_queue(disk);
diff --git a/block/scsi_ioctl.c b/block/scsi_ioctl.c
index 78199c08ec92..c5b9bcfc0a6d 100644
--- a/block/scsi_ioctl.c
+++ b/block/scsi_ioctl.c
@@ -105,120 +105,12 @@ static int sg_emulated_host(struct request_queue *q, int __user *p)
         return put_user(1, p);
 }
 
-#define CMD_READ_SAFE   0x01
-#define CMD_WRITE_SAFE  0x02
-#define CMD_WARNED      0x04
-#define safe_for_read(cmd)      [cmd] = CMD_READ_SAFE
-#define safe_for_write(cmd)     [cmd] = CMD_WRITE_SAFE
-
-int blk_verify_command(unsigned char *cmd, int has_write_perm)
-{
-        static unsigned char cmd_type[256] = {
-
-                /* Basic read-only commands */
-                safe_for_read(TEST_UNIT_READY),
-                safe_for_read(REQUEST_SENSE),
-                safe_for_read(READ_6),
-                safe_for_read(READ_10),
-                safe_for_read(READ_12),
-                safe_for_read(READ_16),
-                safe_for_read(READ_BUFFER),
-                safe_for_read(READ_DEFECT_DATA),
-                safe_for_read(READ_LONG),
-                safe_for_read(INQUIRY),
-                safe_for_read(MODE_SENSE),
-                safe_for_read(MODE_SENSE_10),
-                safe_for_read(LOG_SENSE),
-                safe_for_read(START_STOP),
-                safe_for_read(GPCMD_VERIFY_10),
-                safe_for_read(VERIFY_16),
-
-                /* Audio CD commands */
-                safe_for_read(GPCMD_PLAY_CD),
-                safe_for_read(GPCMD_PLAY_AUDIO_10),
-                safe_for_read(GPCMD_PLAY_AUDIO_MSF),
-                safe_for_read(GPCMD_PLAY_AUDIO_TI),
-                safe_for_read(GPCMD_PAUSE_RESUME),
-
-                /* CD/DVD data reading */
-                safe_for_read(GPCMD_READ_BUFFER_CAPACITY),
-                safe_for_read(GPCMD_READ_CD),
-                safe_for_read(GPCMD_READ_CD_MSF),
-                safe_for_read(GPCMD_READ_DISC_INFO),
-                safe_for_read(GPCMD_READ_CDVD_CAPACITY),
-                safe_for_read(GPCMD_READ_DVD_STRUCTURE),
-                safe_for_read(GPCMD_READ_HEADER),
-                safe_for_read(GPCMD_READ_TRACK_RZONE_INFO),
-                safe_for_read(GPCMD_READ_SUBCHANNEL),
-                safe_for_read(GPCMD_READ_TOC_PMA_ATIP),
-                safe_for_read(GPCMD_REPORT_KEY),
-                safe_for_read(GPCMD_SCAN),
-                safe_for_read(GPCMD_GET_CONFIGURATION),
-                safe_for_read(GPCMD_READ_FORMAT_CAPACITIES),
-                safe_for_read(GPCMD_GET_EVENT_STATUS_NOTIFICATION),
-                safe_for_read(GPCMD_GET_PERFORMANCE),
-                safe_for_read(GPCMD_SEEK),
-                safe_for_read(GPCMD_STOP_PLAY_SCAN),
-
-                /* Basic writing commands */
-                safe_for_write(WRITE_6),
-                safe_for_write(WRITE_10),
-                safe_for_write(WRITE_VERIFY),
-                safe_for_write(WRITE_12),
-                safe_for_write(WRITE_VERIFY_12),
-                safe_for_write(WRITE_16),
-                safe_for_write(WRITE_LONG),
-                safe_for_write(WRITE_LONG_2),
-                safe_for_write(ERASE),
-                safe_for_write(GPCMD_MODE_SELECT_10),
-                safe_for_write(MODE_SELECT),
-                safe_for_write(LOG_SELECT),
-                safe_for_write(GPCMD_BLANK),
-                safe_for_write(GPCMD_CLOSE_TRACK),
-                safe_for_write(GPCMD_FLUSH_CACHE),
-                safe_for_write(GPCMD_FORMAT_UNIT),
-                safe_for_write(GPCMD_REPAIR_RZONE_TRACK),
-                safe_for_write(GPCMD_RESERVE_RZONE_TRACK),
-                safe_for_write(GPCMD_SEND_DVD_STRUCTURE),
-                safe_for_write(GPCMD_SEND_EVENT),
-                safe_for_write(GPCMD_SEND_KEY),
-                safe_for_write(GPCMD_SEND_OPC),
-                safe_for_write(GPCMD_SEND_CUE_SHEET),
-                safe_for_write(GPCMD_SET_SPEED),
-                safe_for_write(GPCMD_PREVENT_ALLOW_MEDIUM_REMOVAL),
-                safe_for_write(GPCMD_LOAD_UNLOAD),
-                safe_for_write(GPCMD_SET_STREAMING),
-        };
-        unsigned char type = cmd_type[cmd[0]];
-
-        /* Anybody who can open the device can do a read-safe command */
-        if (type & CMD_READ_SAFE)
-                return 0;
-
-        /* Write-safe commands just require a writable open.. */
-        if ((type & CMD_WRITE_SAFE) && has_write_perm)
-                return 0;
-
-        /* And root can do any command.. */
-        if (capable(CAP_SYS_RAWIO))
-                return 0;
-
-        if (!type) {
-                cmd_type[cmd[0]] = CMD_WARNED;
-                printk(KERN_WARNING "scsi: unknown opcode 0x%02x\n", cmd[0]);
-        }
-
-        /* Otherwise fail it with an "Operation not permitted" */
-        return -EPERM;
-}
-EXPORT_SYMBOL_GPL(blk_verify_command);
-
 static int blk_fill_sghdr_rq(struct request_queue *q, struct request *rq,
-                             struct sg_io_hdr *hdr, int has_write_perm)
+                             struct sg_io_hdr *hdr, struct file *file)
 {
         if (copy_from_user(rq->cmd, hdr->cmdp, hdr->cmd_len))
                 return -EFAULT;
-        if (blk_verify_command(rq->cmd, has_write_perm))
+        if (blk_verify_command(file, rq->cmd))
                 return -EPERM;
 
         /*
@@ -287,7 +179,7 @@ static int sg_io(struct file *file, struct request_queue *q,
                 struct gendisk *bd_disk, struct sg_io_hdr *hdr)
 {
         unsigned long start_time;
-        int writing = 0, ret = 0, has_write_perm = 0;
+        int writing = 0, ret = 0;
         struct request *rq;
         char sense[SCSI_SENSE_BUFFERSIZE];
         struct bio *bio;
@@ -316,10 +208,7 @@ static int sg_io(struct file *file, struct request_queue *q,
         if (!rq)
                 return -ENOMEM;
 
-        if (file)
-                has_write_perm = file->f_mode & FMODE_WRITE;
-
-        if (blk_fill_sghdr_rq(q, rq, hdr, has_write_perm)) {
+        if (blk_fill_sghdr_rq(q, rq, hdr, file)) {
                 blk_put_request(rq);
                 return -EFAULT;
         }
@@ -451,7 +340,7 @@ int sg_scsi_ioctl(struct file *file, struct request_queue *q,
         if (in_len && copy_from_user(buffer, sic->data + cmdlen, in_len))
                 goto error;
 
-        err = blk_verify_command(rq->cmd, file->f_mode & FMODE_WRITE);
+        err = blk_verify_command(file, rq->cmd);
         if (err)
                 goto error;
 
diff --git a/drivers/scsi/sg.c b/drivers/scsi/sg.c
index ea0edd1b2e76..f7abccaffaec 100644
--- a/drivers/scsi/sg.c
+++ b/drivers/scsi/sg.c
@@ -182,8 +182,9 @@ static int sg_build_sgat(Sg_scatter_hold * schp, const Sg_fd * sfp,
                          int tablesize);
 static ssize_t sg_new_read(Sg_fd * sfp, char __user *buf, size_t count,
                            Sg_request * srp);
-static ssize_t sg_new_write(Sg_fd * sfp, const char __user *buf, size_t count,
-                            int blocking, int read_only, Sg_request ** o_srp);
+static ssize_t sg_new_write(Sg_fd *sfp, struct file *file,
+                        const char __user *buf, size_t count, int blocking,
+                        int read_only, Sg_request **o_srp);
 static int sg_common_write(Sg_fd * sfp, Sg_request * srp,
                            unsigned char *cmnd, int timeout, int blocking);
 static int sg_u_iovec(sg_io_hdr_t * hp, int sg_num, int ind,
@@ -204,7 +205,6 @@ static Sg_request *sg_get_rq_mark(Sg_fd * sfp, int pack_id);
 static Sg_request *sg_add_request(Sg_fd * sfp);
 static int sg_remove_request(Sg_fd * sfp, Sg_request * srp);
 static int sg_res_in_use(Sg_fd * sfp);
-static int sg_allow_access(unsigned char opcode, char dev_type);
 static int sg_build_direct(Sg_request * srp, Sg_fd * sfp, int dxfer_len);
 static Sg_device *sg_get_dev(int dev);
 #ifdef CONFIG_SCSI_PROC_FS
@@ -544,7 +544,7 @@ sg_write(struct file *filp, const char __user *buf, size_t count, loff_t * ppos)
                 return -EFAULT;
         blocking = !(filp->f_flags & O_NONBLOCK);
         if (old_hdr.reply_len < 0)
-                return sg_new_write(sfp, buf, count, blocking, 0, NULL);
+                return sg_new_write(sfp, filp, buf, count, blocking, 0, NULL);
         if (count < (SZ_SG_HEADER + 6))
                 return -EIO;    /* The minimum scsi command length is 6 bytes. */
 
@@ -621,8 +621,9 @@ sg_write(struct file *filp, const char __user *buf, size_t count, loff_t * ppos)
 }
 
 static ssize_t
-sg_new_write(Sg_fd * sfp, const char __user *buf, size_t count,
-             int blocking, int read_only, Sg_request ** o_srp)
+sg_new_write(Sg_fd *sfp, struct file *file, const char __user *buf,
+                 size_t count, int blocking, int read_only,
+                 Sg_request **o_srp)
 {
         int k;
         Sg_request *srp;
@@ -678,8 +679,7 @@ sg_new_write(Sg_fd * sfp, const char __user *buf, size_t count,
                 sg_remove_request(sfp, srp);
                 return -EFAULT;
         }
-        if (read_only &&
-            (!sg_allow_access(cmnd[0], sfp->parentdp->device->type))) {
+        if (read_only && (!blk_verify_command(file, cmnd))) {
                 sg_remove_request(sfp, srp);
                 return -EPERM;
         }
@@ -799,7 +799,7 @@ sg_ioctl(struct inode *inode, struct file *filp,
                         if (!access_ok(VERIFY_WRITE, p, SZ_SG_IO_HDR))
                                 return -EFAULT;
                         result =
-                            sg_new_write(sfp, p, SZ_SG_IO_HDR,
+                            sg_new_write(sfp, filp, p, SZ_SG_IO_HDR,
                                          blocking, read_only, &srp);
                         if (result < 0)
                                 return result;
@@ -1048,7 +1048,7 @@ sg_ioctl(struct inode *inode, struct file *filp,
 
                         if (copy_from_user(&opcode, siocp->data, 1))
                                 return -EFAULT;
-                        if (!sg_allow_access(opcode, sdp->device->type))
+                        if (!blk_verify_command(filp, &opcode))
                                 return -EPERM;
                 }
                 return sg_scsi_ioctl(filp, sdp->device->request_queue, NULL, p);
@@ -2506,26 +2506,6 @@ sg_page_free(struct page *page, int size)
 #define MAINTENANCE_IN_CMD 0xa3
 #endif
 
-static unsigned char allow_ops[] = { TEST_UNIT_READY, REQUEST_SENSE,
-        INQUIRY, READ_CAPACITY, READ_BUFFER, READ_6, READ_10, READ_12,
-        READ_16, MODE_SENSE, MODE_SENSE_10, LOG_SENSE, REPORT_LUNS,
-        SERVICE_ACTION_IN, RECEIVE_DIAGNOSTIC, READ_LONG, MAINTENANCE_IN_CMD
-};
-
-static int
-sg_allow_access(unsigned char opcode, char dev_type)
-{
-        int k;
-
-        if (TYPE_SCANNER == dev_type)   /* TYPE_ROM maybe burner */
-                return 1;
-        for (k = 0; k < sizeof (allow_ops); ++k) {
-                if (opcode == allow_ops[k])
-                        return 1;
-        }
-        return 0;
-}
-
 #ifdef CONFIG_SCSI_PROC_FS
 static int
 sg_idr_max_id(int id, void *p, void *data)
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index d3ae9ad97213..a842b776d099 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -671,7 +671,6 @@ extern int blk_execute_rq(struct request_queue *, struct gendisk *,
                           struct request *, int);
 extern void blk_execute_rq_nowait(struct request_queue *, struct gendisk *,
                                   struct request *, int, rq_end_io_fn *);
-extern int blk_verify_command(unsigned char *, int);
 extern void blk_unplug(struct request_queue *q);
 
 static inline struct request_queue *bdev_get_queue(struct block_device *bdev)
@@ -797,6 +796,15 @@ static inline struct request *blk_map_queue_find_tag(struct blk_queue_tag *bqt,
 
 extern int blkdev_issue_flush(struct block_device *, sector_t *);
 
+/*
+* command filter functions
+*/
+extern int blk_verify_command(struct file *file, unsigned char *cmd);
+extern int blk_cmd_filter_verify_command(struct blk_scsi_cmd_filter *filter,
+                                         unsigned char *cmd, mode_t *f_mode);
+extern int blk_register_filter(struct gendisk *disk);
+extern void blk_unregister_filter(struct gendisk *disk);
+
 #define MAX_PHYS_SEGMENTS 128
 #define MAX_HW_SEGMENTS 128
 #define SAFE_MAX_SECTORS 255
diff --git a/include/linux/genhd.h b/include/linux/genhd.h
index 524ec96f5a23..e8787417f65a 100644
--- a/include/linux/genhd.h
+++ b/include/linux/genhd.h
@@ -110,6 +110,14 @@ struct hd_struct {
 #define GENHD_FL_SUPPRESS_PARTITION_INFO        32
 #define GENHD_FL_FAIL                           64
 
+#define BLK_SCSI_MAX_CMDS       (256)
+#define BLK_SCSI_CMD_PER_LONG   (BLK_SCSI_MAX_CMDS / (sizeof(long) * 8))
+
+struct blk_scsi_cmd_filter {
+        unsigned long read_ok[BLK_SCSI_CMD_PER_LONG];
+        unsigned long write_ok[BLK_SCSI_CMD_PER_LONG];
+        struct kobject kobj;
+};
 
 struct gendisk {
         int major;                      /* major number of driver */
@@ -120,6 +128,7 @@ struct gendisk {
         struct hd_struct **part;        /* [indexed by minor] */
         struct block_device_operations *fops;
         struct request_queue *queue;
+        struct blk_scsi_cmd_filter cmd_filter;
         void *private_data;
         sector_t capacity;