separate partition format handling from generic code
Al Viro [Fri, 16 Sep 2011 04:45:36 +0000 (00:45 -0400)]
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

block/Makefile
block/partition-generic.c [new file with mode: 0644]
block/partitions/check.c
block/partitions/check.h

index 3199c0c..39b76ba 100644 (file)
@@ -6,7 +6,7 @@ obj-$(CONFIG_BLOCK) := elevator.o blk-core.o blk-tag.o blk-sysfs.o \
                        blk-flush.o blk-settings.o blk-ioc.o blk-map.o \
                        blk-exec.o blk-merge.o blk-softirq.o blk-timeout.o \
                        blk-iopoll.o blk-lib.o ioctl.o genhd.o scsi_ioctl.o \
-                       partitions/
+                       partition-generic.o partitions/
 
 obj-$(CONFIG_BLK_DEV_BSG)      += bsg.o
 obj-$(CONFIG_BLK_DEV_BSGLIB)   += bsg-lib.o
diff --git a/block/partition-generic.c b/block/partition-generic.c
new file mode 100644 (file)
index 0000000..d06ec1c
--- /dev/null
@@ -0,0 +1,537 @@
+/*
+ *  Code extracted from drivers/block/genhd.c
+ *  Copyright (C) 1991-1998  Linus Torvalds
+ *  Re-organised Feb 1998 Russell King
+ *
+ *  We now have independent partition support from the
+ *  block drivers, which allows all the partition code to
+ *  be grouped in one location, and it to be mostly self
+ *  contained.
+ */
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/fs.h>
+#include <linux/slab.h>
+#include <linux/kmod.h>
+#include <linux/ctype.h>
+#include <linux/genhd.h>
+#include <linux/blktrace_api.h>
+
+#include "partitions/check.h"
+
+#ifdef CONFIG_BLK_DEV_MD
+extern void md_autodetect_dev(dev_t dev);
+#endif
+/*
+ * disk_name() is used by partition check code and the genhd driver.
+ * It formats the devicename of the indicated disk into
+ * the supplied buffer (of size at least 32), and returns
+ * a pointer to that same buffer (for convenience).
+ */
+
+char *disk_name(struct gendisk *hd, int partno, char *buf)
+{
+       if (!partno)
+               snprintf(buf, BDEVNAME_SIZE, "%s", hd->disk_name);
+       else if (isdigit(hd->disk_name[strlen(hd->disk_name)-1]))
+               snprintf(buf, BDEVNAME_SIZE, "%sp%d", hd->disk_name, partno);
+       else
+               snprintf(buf, BDEVNAME_SIZE, "%s%d", hd->disk_name, partno);
+
+       return buf;
+}
+
+const char *bdevname(struct block_device *bdev, char *buf)
+{
+       return disk_name(bdev->bd_disk, bdev->bd_part->partno, buf);
+}
+
+EXPORT_SYMBOL(bdevname);
+
+/*
+ * There's very little reason to use this, you should really
+ * have a struct block_device just about everywhere and use
+ * bdevname() instead.
+ */
+const char *__bdevname(dev_t dev, char *buffer)
+{
+       scnprintf(buffer, BDEVNAME_SIZE, "unknown-block(%u,%u)",
+                               MAJOR(dev), MINOR(dev));
+       return buffer;
+}
+
+EXPORT_SYMBOL(__bdevname);
+
+static ssize_t part_partition_show(struct device *dev,
+                                  struct device_attribute *attr, char *buf)
+{
+       struct hd_struct *p = dev_to_part(dev);
+
+       return sprintf(buf, "%d\n", p->partno);
+}
+
+static ssize_t part_start_show(struct device *dev,
+                              struct device_attribute *attr, char *buf)
+{
+       struct hd_struct *p = dev_to_part(dev);
+
+       return sprintf(buf, "%llu\n",(unsigned long long)p->start_sect);
+}
+
+ssize_t part_size_show(struct device *dev,
+                      struct device_attribute *attr, char *buf)
+{
+       struct hd_struct *p = dev_to_part(dev);
+       return sprintf(buf, "%llu\n",(unsigned long long)p->nr_sects);
+}
+
+static ssize_t part_ro_show(struct device *dev,
+                           struct device_attribute *attr, char *buf)
+{
+       struct hd_struct *p = dev_to_part(dev);
+       return sprintf(buf, "%d\n", p->policy ? 1 : 0);
+}
+
+static ssize_t part_alignment_offset_show(struct device *dev,
+                                         struct device_attribute *attr, char *buf)
+{
+       struct hd_struct *p = dev_to_part(dev);
+       return sprintf(buf, "%llu\n", (unsigned long long)p->alignment_offset);
+}
+
+static ssize_t part_discard_alignment_show(struct device *dev,
+                                          struct device_attribute *attr, char *buf)
+{
+       struct hd_struct *p = dev_to_part(dev);
+       return sprintf(buf, "%u\n", p->discard_alignment);
+}
+
+ssize_t part_stat_show(struct device *dev,
+                      struct device_attribute *attr, char *buf)
+{
+       struct hd_struct *p = dev_to_part(dev);
+       int cpu;
+
+       cpu = part_stat_lock();
+       part_round_stats(cpu, p);
+       part_stat_unlock();
+       return sprintf(buf,
+               "%8lu %8lu %8llu %8u "
+               "%8lu %8lu %8llu %8u "
+               "%8u %8u %8u"
+               "\n",
+               part_stat_read(p, ios[READ]),
+               part_stat_read(p, merges[READ]),
+               (unsigned long long)part_stat_read(p, sectors[READ]),
+               jiffies_to_msecs(part_stat_read(p, ticks[READ])),
+               part_stat_read(p, ios[WRITE]),
+               part_stat_read(p, merges[WRITE]),
+               (unsigned long long)part_stat_read(p, sectors[WRITE]),
+               jiffies_to_msecs(part_stat_read(p, ticks[WRITE])),
+               part_in_flight(p),
+               jiffies_to_msecs(part_stat_read(p, io_ticks)),
+               jiffies_to_msecs(part_stat_read(p, time_in_queue)));
+}
+
+ssize_t part_inflight_show(struct device *dev,
+                       struct device_attribute *attr, char *buf)
+{
+       struct hd_struct *p = dev_to_part(dev);
+
+       return sprintf(buf, "%8u %8u\n", atomic_read(&p->in_flight[0]),
+               atomic_read(&p->in_flight[1]));
+}
+
+#ifdef CONFIG_FAIL_MAKE_REQUEST
+ssize_t part_fail_show(struct device *dev,
+                      struct device_attribute *attr, char *buf)
+{
+       struct hd_struct *p = dev_to_part(dev);
+
+       return sprintf(buf, "%d\n", p->make_it_fail);
+}
+
+ssize_t part_fail_store(struct device *dev,
+                       struct device_attribute *attr,
+                       const char *buf, size_t count)
+{
+       struct hd_struct *p = dev_to_part(dev);
+       int i;
+
+       if (count > 0 && sscanf(buf, "%d", &i) > 0)
+               p->make_it_fail = (i == 0) ? 0 : 1;
+
+       return count;
+}
+#endif
+
+static DEVICE_ATTR(partition, S_IRUGO, part_partition_show, NULL);
+static DEVICE_ATTR(start, S_IRUGO, part_start_show, NULL);
+static DEVICE_ATTR(size, S_IRUGO, part_size_show, NULL);
+static DEVICE_ATTR(ro, S_IRUGO, part_ro_show, NULL);
+static DEVICE_ATTR(alignment_offset, S_IRUGO, part_alignment_offset_show, NULL);
+static DEVICE_ATTR(discard_alignment, S_IRUGO, part_discard_alignment_show,
+                  NULL);
+static DEVICE_ATTR(stat, S_IRUGO, part_stat_show, NULL);
+static DEVICE_ATTR(inflight, S_IRUGO, part_inflight_show, NULL);
+#ifdef CONFIG_FAIL_MAKE_REQUEST
+static struct device_attribute dev_attr_fail =
+       __ATTR(make-it-fail, S_IRUGO|S_IWUSR, part_fail_show, part_fail_store);
+#endif
+
+static struct attribute *part_attrs[] = {
+       &dev_attr_partition.attr,
+       &dev_attr_start.attr,
+       &dev_attr_size.attr,
+       &dev_attr_ro.attr,
+       &dev_attr_alignment_offset.attr,
+       &dev_attr_discard_alignment.attr,
+       &dev_attr_stat.attr,
+       &dev_attr_inflight.attr,
+#ifdef CONFIG_FAIL_MAKE_REQUEST
+       &dev_attr_fail.attr,
+#endif
+       NULL
+};
+
+static struct attribute_group part_attr_group = {
+       .attrs = part_attrs,
+};
+
+static const struct attribute_group *part_attr_groups[] = {
+       &part_attr_group,
+#ifdef CONFIG_BLK_DEV_IO_TRACE
+       &blk_trace_attr_group,
+#endif
+       NULL
+};
+
+static void part_release(struct device *dev)
+{
+       struct hd_struct *p = dev_to_part(dev);
+       free_part_stats(p);
+       free_part_info(p);
+       kfree(p);
+}
+
+struct device_type part_type = {
+       .name           = "partition",
+       .groups         = part_attr_groups,
+       .release        = part_release,
+};
+
+static void delete_partition_rcu_cb(struct rcu_head *head)
+{
+       struct hd_struct *part = container_of(head, struct hd_struct, rcu_head);
+
+       part->start_sect = 0;
+       part->nr_sects = 0;
+       part_stat_set_all(part, 0);
+       put_device(part_to_dev(part));
+}
+
+void __delete_partition(struct hd_struct *part)
+{
+       call_rcu(&part->rcu_head, delete_partition_rcu_cb);
+}
+
+void delete_partition(struct gendisk *disk, int partno)
+{
+       struct disk_part_tbl *ptbl = disk->part_tbl;
+       struct hd_struct *part;
+
+       if (partno >= ptbl->len)
+               return;
+
+       part = ptbl->part[partno];
+       if (!part)
+               return;
+
+       blk_free_devt(part_devt(part));
+       rcu_assign_pointer(ptbl->part[partno], NULL);
+       rcu_assign_pointer(ptbl->last_lookup, NULL);
+       kobject_put(part->holder_dir);
+       device_del(part_to_dev(part));
+
+       hd_struct_put(part);
+}
+
+static ssize_t whole_disk_show(struct device *dev,
+                              struct device_attribute *attr, char *buf)
+{
+       return 0;
+}
+static DEVICE_ATTR(whole_disk, S_IRUSR | S_IRGRP | S_IROTH,
+                  whole_disk_show, NULL);
+
+struct hd_struct *add_partition(struct gendisk *disk, int partno,
+                               sector_t start, sector_t len, int flags,
+                               struct partition_meta_info *info)
+{
+       struct hd_struct *p;
+       dev_t devt = MKDEV(0, 0);
+       struct device *ddev = disk_to_dev(disk);
+       struct device *pdev;
+       struct disk_part_tbl *ptbl;
+       const char *dname;
+       int err;
+
+       err = disk_expand_part_tbl(disk, partno);
+       if (err)
+               return ERR_PTR(err);
+       ptbl = disk->part_tbl;
+
+       if (ptbl->part[partno])
+               return ERR_PTR(-EBUSY);
+
+       p = kzalloc(sizeof(*p), GFP_KERNEL);
+       if (!p)
+               return ERR_PTR(-EBUSY);
+
+       if (!init_part_stats(p)) {
+               err = -ENOMEM;
+               goto out_free;
+       }
+       pdev = part_to_dev(p);
+
+       p->start_sect = start;
+       p->alignment_offset =
+               queue_limit_alignment_offset(&disk->queue->limits, start);
+       p->discard_alignment =
+               queue_limit_discard_alignment(&disk->queue->limits, start);
+       p->nr_sects = len;
+       p->partno = partno;
+       p->policy = get_disk_ro(disk);
+
+       if (info) {
+               struct partition_meta_info *pinfo = alloc_part_info(disk);
+               if (!pinfo)
+                       goto out_free_stats;
+               memcpy(pinfo, info, sizeof(*info));
+               p->info = pinfo;
+       }
+
+       dname = dev_name(ddev);
+       if (isdigit(dname[strlen(dname) - 1]))
+               dev_set_name(pdev, "%sp%d", dname, partno);
+       else
+               dev_set_name(pdev, "%s%d", dname, partno);
+
+       device_initialize(pdev);
+       pdev->class = &block_class;
+       pdev->type = &part_type;
+       pdev->parent = ddev;
+
+       err = blk_alloc_devt(p, &devt);
+       if (err)
+               goto out_free_info;
+       pdev->devt = devt;
+
+       /* delay uevent until 'holders' subdir is created */
+       dev_set_uevent_suppress(pdev, 1);
+       err = device_add(pdev);
+       if (err)
+               goto out_put;
+
+       err = -ENOMEM;
+       p->holder_dir = kobject_create_and_add("holders", &pdev->kobj);
+       if (!p->holder_dir)
+               goto out_del;
+
+       dev_set_uevent_suppress(pdev, 0);
+       if (flags & ADDPART_FLAG_WHOLEDISK) {
+               err = device_create_file(pdev, &dev_attr_whole_disk);
+               if (err)
+                       goto out_del;
+       }
+
+       /* everything is up and running, commence */
+       rcu_assign_pointer(ptbl->part[partno], p);
+
+       /* suppress uevent if the disk suppresses it */
+       if (!dev_get_uevent_suppress(ddev))
+               kobject_uevent(&pdev->kobj, KOBJ_ADD);
+
+       hd_ref_init(p);
+       return p;
+
+out_free_info:
+       free_part_info(p);
+out_free_stats:
+       free_part_stats(p);
+out_free:
+       kfree(p);
+       return ERR_PTR(err);
+out_del:
+       kobject_put(p->holder_dir);
+       device_del(pdev);
+out_put:
+       put_device(pdev);
+       blk_free_devt(devt);
+       return ERR_PTR(err);
+}
+
+static bool disk_unlock_native_capacity(struct gendisk *disk)
+{
+       const struct block_device_operations *bdops = disk->fops;
+
+       if (bdops->unlock_native_capacity &&
+           !(disk->flags & GENHD_FL_NATIVE_CAPACITY)) {
+               printk(KERN_CONT "enabling native capacity\n");
+               bdops->unlock_native_capacity(disk);
+               disk->flags |= GENHD_FL_NATIVE_CAPACITY;
+               return true;
+       } else {
+               printk(KERN_CONT "truncated\n");
+               return false;
+       }
+}
+
+int rescan_partitions(struct gendisk *disk, struct block_device *bdev)
+{
+       struct parsed_partitions *state = NULL;
+       struct disk_part_iter piter;
+       struct hd_struct *part;
+       int p, highest, res;
+rescan:
+       if (state && !IS_ERR(state)) {
+               kfree(state);
+               state = NULL;
+       }
+
+       if (bdev->bd_part_count)
+               return -EBUSY;
+       res = invalidate_partition(disk, 0);
+       if (res)
+               return res;
+
+       disk_part_iter_init(&piter, disk, DISK_PITER_INCL_EMPTY);
+       while ((part = disk_part_iter_next(&piter)))
+               delete_partition(disk, part->partno);
+       disk_part_iter_exit(&piter);
+
+       if (disk->fops->revalidate_disk)
+               disk->fops->revalidate_disk(disk);
+       check_disk_size_change(disk, bdev);
+       bdev->bd_invalidated = 0;
+       if (!get_capacity(disk) || !(state = check_partition(disk, bdev)))
+               return 0;
+       if (IS_ERR(state)) {
+               /*
+                * I/O error reading the partition table.  If any
+                * partition code tried to read beyond EOD, retry
+                * after unlocking native capacity.
+                */
+               if (PTR_ERR(state) == -ENOSPC) {
+                       printk(KERN_WARNING "%s: partition table beyond EOD, ",
+                              disk->disk_name);
+                       if (disk_unlock_native_capacity(disk))
+                               goto rescan;
+               }
+               return -EIO;
+       }
+       /*
+        * If any partition code tried to read beyond EOD, try
+        * unlocking native capacity even if partition table is
+        * successfully read as we could be missing some partitions.
+        */
+       if (state->access_beyond_eod) {
+               printk(KERN_WARNING
+                      "%s: partition table partially beyond EOD, ",
+                      disk->disk_name);
+               if (disk_unlock_native_capacity(disk))
+                       goto rescan;
+       }
+
+       /* tell userspace that the media / partition table may have changed */
+       kobject_uevent(&disk_to_dev(disk)->kobj, KOBJ_CHANGE);
+
+       /* Detect the highest partition number and preallocate
+        * disk->part_tbl.  This is an optimization and not strictly
+        * necessary.
+        */
+       for (p = 1, highest = 0; p < state->limit; p++)
+               if (state->parts[p].size)
+                       highest = p;
+
+       disk_expand_part_tbl(disk, highest);
+
+       /* add partitions */
+       for (p = 1; p < state->limit; p++) {
+               sector_t size, from;
+               struct partition_meta_info *info = NULL;
+
+               size = state->parts[p].size;
+               if (!size)
+                       continue;
+
+               from = state->parts[p].from;
+               if (from >= get_capacity(disk)) {
+                       printk(KERN_WARNING
+                              "%s: p%d start %llu is beyond EOD, ",
+                              disk->disk_name, p, (unsigned long long) from);
+                       if (disk_unlock_native_capacity(disk))
+                               goto rescan;
+                       continue;
+               }
+
+               if (from + size > get_capacity(disk)) {
+                       printk(KERN_WARNING
+                              "%s: p%d size %llu extends beyond EOD, ",
+                              disk->disk_name, p, (unsigned long long) size);
+
+                       if (disk_unlock_native_capacity(disk)) {
+                               /* free state and restart */
+                               goto rescan;
+                       } else {
+                               /*
+                                * we can not ignore partitions of broken tables
+                                * created by for example camera firmware, but
+                                * we limit them to the end of the disk to avoid
+                                * creating invalid block devices
+                                */
+                               size = get_capacity(disk) - from;
+                       }
+               }
+
+               if (state->parts[p].has_info)
+                       info = &state->parts[p].info;
+               part = add_partition(disk, p, from, size,
+                                    state->parts[p].flags,
+                                    &state->parts[p].info);
+               if (IS_ERR(part)) {
+                       printk(KERN_ERR " %s: p%d could not be added: %ld\n",
+                              disk->disk_name, p, -PTR_ERR(part));
+                       continue;
+               }
+#ifdef CONFIG_BLK_DEV_MD
+               if (state->parts[p].flags & ADDPART_FLAG_RAID)
+                       md_autodetect_dev(part_to_dev(part)->devt);
+#endif
+       }
+       kfree(state);
+       return 0;
+}
+
+unsigned char *read_dev_sector(struct block_device *bdev, sector_t n, Sector *p)
+{
+       struct address_space *mapping = bdev->bd_inode->i_mapping;
+       struct page *page;
+
+       page = read_mapping_page(mapping, (pgoff_t)(n >> (PAGE_CACHE_SHIFT-9)),
+                                NULL);
+       if (!IS_ERR(page)) {
+               if (PageError(page))
+                       goto fail;
+               p->v = page;
+               return (unsigned char *)page_address(page) +  ((n & ((1 << (PAGE_CACHE_SHIFT - 9)) - 1)) << 9);
+fail:
+               page_cache_release(page);
+       }
+       p->v = NULL;
+       return NULL;
+}
+
+EXPORT_SYMBOL(read_dev_sector);
index e3c63d1..bc90867 100644 (file)
  *  Added needed MAJORS for new pairs, {hdi,hdj}, {hdk,hdl}
  */
 
-#include <linux/init.h>
-#include <linux/module.h>
-#include <linux/fs.h>
 #include <linux/slab.h>
-#include <linux/kmod.h>
 #include <linux/ctype.h>
 #include <linux/genhd.h>
-#include <linux/blktrace_api.h>
 
 #include "check.h"
 
 #include "karma.h"
 #include "sysv68.h"
 
-#ifdef CONFIG_BLK_DEV_MD
-extern void md_autodetect_dev(dev_t dev);
-#endif
-
 int warn_no_part = 1; /*This is ugly: should make genhd removable media aware*/
 
 static int (*check_part[])(struct parsed_partitions *) = {
@@ -114,48 +105,8 @@ static int (*check_part[])(struct parsed_partitions *) = {
 #endif
        NULL
 };
-/*
- * disk_name() is used by partition check code and the genhd driver.
- * It formats the devicename of the indicated disk into
- * the supplied buffer (of size at least 32), and returns
- * a pointer to that same buffer (for convenience).
- */
-
-char *disk_name(struct gendisk *hd, int partno, char *buf)
-{
-       if (!partno)
-               snprintf(buf, BDEVNAME_SIZE, "%s", hd->disk_name);
-       else if (isdigit(hd->disk_name[strlen(hd->disk_name)-1]))
-               snprintf(buf, BDEVNAME_SIZE, "%sp%d", hd->disk_name, partno);
-       else
-               snprintf(buf, BDEVNAME_SIZE, "%s%d", hd->disk_name, partno);
-
-       return buf;
-}
-
-const char *bdevname(struct block_device *bdev, char *buf)
-{
-       return disk_name(bdev->bd_disk, bdev->bd_part->partno, buf);
-}
-
-EXPORT_SYMBOL(bdevname);
-
-/*
- * There's very little reason to use this, you should really
- * have a struct block_device just about everywhere and use
- * bdevname() instead.
- */
-const char *__bdevname(dev_t dev, char *buffer)
-{
-       scnprintf(buffer, BDEVNAME_SIZE, "unknown-block(%u,%u)",
-                               MAJOR(dev), MINOR(dev));
-       return buffer;
-}
-
-EXPORT_SYMBOL(__bdevname);
 
-static struct parsed_partitions *
+struct parsed_partitions *
 check_partition(struct gendisk *hd, struct block_device *bdev)
 {
        struct parsed_partitions *state;
@@ -213,475 +164,3 @@ check_partition(struct gendisk *hd, struct block_device *bdev)
        kfree(state);
        return ERR_PTR(res);
 }
-
-static ssize_t part_partition_show(struct device *dev,
-                                  struct device_attribute *attr, char *buf)
-{
-       struct hd_struct *p = dev_to_part(dev);
-
-       return sprintf(buf, "%d\n", p->partno);
-}
-
-static ssize_t part_start_show(struct device *dev,
-                              struct device_attribute *attr, char *buf)
-{
-       struct hd_struct *p = dev_to_part(dev);
-
-       return sprintf(buf, "%llu\n",(unsigned long long)p->start_sect);
-}
-
-ssize_t part_size_show(struct device *dev,
-                      struct device_attribute *attr, char *buf)
-{
-       struct hd_struct *p = dev_to_part(dev);
-       return sprintf(buf, "%llu\n",(unsigned long long)p->nr_sects);
-}
-
-static ssize_t part_ro_show(struct device *dev,
-                           struct device_attribute *attr, char *buf)
-{
-       struct hd_struct *p = dev_to_part(dev);
-       return sprintf(buf, "%d\n", p->policy ? 1 : 0);
-}
-
-static ssize_t part_alignment_offset_show(struct device *dev,
-                                         struct device_attribute *attr, char *buf)
-{
-       struct hd_struct *p = dev_to_part(dev);
-       return sprintf(buf, "%llu\n", (unsigned long long)p->alignment_offset);
-}
-
-static ssize_t part_discard_alignment_show(struct device *dev,
-                                          struct device_attribute *attr, char *buf)
-{
-       struct hd_struct *p = dev_to_part(dev);
-       return sprintf(buf, "%u\n", p->discard_alignment);
-}
-
-ssize_t part_stat_show(struct device *dev,
-                      struct device_attribute *attr, char *buf)
-{
-       struct hd_struct *p = dev_to_part(dev);
-       int cpu;
-
-       cpu = part_stat_lock();
-       part_round_stats(cpu, p);
-       part_stat_unlock();
-       return sprintf(buf,
-               "%8lu %8lu %8llu %8u "
-               "%8lu %8lu %8llu %8u "
-               "%8u %8u %8u"
-               "\n",
-               part_stat_read(p, ios[READ]),
-               part_stat_read(p, merges[READ]),
-               (unsigned long long)part_stat_read(p, sectors[READ]),
-               jiffies_to_msecs(part_stat_read(p, ticks[READ])),
-               part_stat_read(p, ios[WRITE]),
-               part_stat_read(p, merges[WRITE]),
-               (unsigned long long)part_stat_read(p, sectors[WRITE]),
-               jiffies_to_msecs(part_stat_read(p, ticks[WRITE])),
-               part_in_flight(p),
-               jiffies_to_msecs(part_stat_read(p, io_ticks)),
-               jiffies_to_msecs(part_stat_read(p, time_in_queue)));
-}
-
-ssize_t part_inflight_show(struct device *dev,
-                       struct device_attribute *attr, char *buf)
-{
-       struct hd_struct *p = dev_to_part(dev);
-
-       return sprintf(buf, "%8u %8u\n", atomic_read(&p->in_flight[0]),
-               atomic_read(&p->in_flight[1]));
-}
-
-#ifdef CONFIG_FAIL_MAKE_REQUEST
-ssize_t part_fail_show(struct device *dev,
-                      struct device_attribute *attr, char *buf)
-{
-       struct hd_struct *p = dev_to_part(dev);
-
-       return sprintf(buf, "%d\n", p->make_it_fail);
-}
-
-ssize_t part_fail_store(struct device *dev,
-                       struct device_attribute *attr,
-                       const char *buf, size_t count)
-{
-       struct hd_struct *p = dev_to_part(dev);
-       int i;
-
-       if (count > 0 && sscanf(buf, "%d", &i) > 0)
-               p->make_it_fail = (i == 0) ? 0 : 1;
-
-       return count;
-}
-#endif
-
-static DEVICE_ATTR(partition, S_IRUGO, part_partition_show, NULL);
-static DEVICE_ATTR(start, S_IRUGO, part_start_show, NULL);
-static DEVICE_ATTR(size, S_IRUGO, part_size_show, NULL);
-static DEVICE_ATTR(ro, S_IRUGO, part_ro_show, NULL);
-static DEVICE_ATTR(alignment_offset, S_IRUGO, part_alignment_offset_show, NULL);
-static DEVICE_ATTR(discard_alignment, S_IRUGO, part_discard_alignment_show,
-                  NULL);
-static DEVICE_ATTR(stat, S_IRUGO, part_stat_show, NULL);
-static DEVICE_ATTR(inflight, S_IRUGO, part_inflight_show, NULL);
-#ifdef CONFIG_FAIL_MAKE_REQUEST
-static struct device_attribute dev_attr_fail =
-       __ATTR(make-it-fail, S_IRUGO|S_IWUSR, part_fail_show, part_fail_store);
-#endif
-
-static struct attribute *part_attrs[] = {
-       &dev_attr_partition.attr,
-       &dev_attr_start.attr,
-       &dev_attr_size.attr,
-       &dev_attr_ro.attr,
-       &dev_attr_alignment_offset.attr,
-       &dev_attr_discard_alignment.attr,
-       &dev_attr_stat.attr,
-       &dev_attr_inflight.attr,
-#ifdef CONFIG_FAIL_MAKE_REQUEST
-       &dev_attr_fail.attr,
-#endif
-       NULL
-};
-
-static struct attribute_group part_attr_group = {
-       .attrs = part_attrs,
-};
-
-static const struct attribute_group *part_attr_groups[] = {
-       &part_attr_group,
-#ifdef CONFIG_BLK_DEV_IO_TRACE
-       &blk_trace_attr_group,
-#endif
-       NULL
-};
-
-static void part_release(struct device *dev)
-{
-       struct hd_struct *p = dev_to_part(dev);
-       free_part_stats(p);
-       free_part_info(p);
-       kfree(p);
-}
-
-struct device_type part_type = {
-       .name           = "partition",
-       .groups         = part_attr_groups,
-       .release        = part_release,
-};
-
-static void delete_partition_rcu_cb(struct rcu_head *head)
-{
-       struct hd_struct *part = container_of(head, struct hd_struct, rcu_head);
-
-       part->start_sect = 0;
-       part->nr_sects = 0;
-       part_stat_set_all(part, 0);
-       put_device(part_to_dev(part));
-}
-
-void __delete_partition(struct hd_struct *part)
-{
-       call_rcu(&part->rcu_head, delete_partition_rcu_cb);
-}
-
-void delete_partition(struct gendisk *disk, int partno)
-{
-       struct disk_part_tbl *ptbl = disk->part_tbl;
-       struct hd_struct *part;
-
-       if (partno >= ptbl->len)
-               return;
-
-       part = ptbl->part[partno];
-       if (!part)
-               return;
-
-       blk_free_devt(part_devt(part));
-       rcu_assign_pointer(ptbl->part[partno], NULL);
-       rcu_assign_pointer(ptbl->last_lookup, NULL);
-       kobject_put(part->holder_dir);
-       device_del(part_to_dev(part));
-
-       hd_struct_put(part);
-}
-
-static ssize_t whole_disk_show(struct device *dev,
-                              struct device_attribute *attr, char *buf)
-{
-       return 0;
-}
-static DEVICE_ATTR(whole_disk, S_IRUSR | S_IRGRP | S_IROTH,
-                  whole_disk_show, NULL);
-
-struct hd_struct *add_partition(struct gendisk *disk, int partno,
-                               sector_t start, sector_t len, int flags,
-                               struct partition_meta_info *info)
-{
-       struct hd_struct *p;
-       dev_t devt = MKDEV(0, 0);
-       struct device *ddev = disk_to_dev(disk);
-       struct device *pdev;
-       struct disk_part_tbl *ptbl;
-       const char *dname;
-       int err;
-
-       err = disk_expand_part_tbl(disk, partno);
-       if (err)
-               return ERR_PTR(err);
-       ptbl = disk->part_tbl;
-
-       if (ptbl->part[partno])
-               return ERR_PTR(-EBUSY);
-
-       p = kzalloc(sizeof(*p), GFP_KERNEL);
-       if (!p)
-               return ERR_PTR(-EBUSY);
-
-       if (!init_part_stats(p)) {
-               err = -ENOMEM;
-               goto out_free;
-       }
-       pdev = part_to_dev(p);
-
-       p->start_sect = start;
-       p->alignment_offset =
-               queue_limit_alignment_offset(&disk->queue->limits, start);
-       p->discard_alignment =
-               queue_limit_discard_alignment(&disk->queue->limits, start);
-       p->nr_sects = len;
-       p->partno = partno;
-       p->policy = get_disk_ro(disk);
-
-       if (info) {
-               struct partition_meta_info *pinfo = alloc_part_info(disk);
-               if (!pinfo)
-                       goto out_free_stats;
-               memcpy(pinfo, info, sizeof(*info));
-               p->info = pinfo;
-       }
-
-       dname = dev_name(ddev);
-       if (isdigit(dname[strlen(dname) - 1]))
-               dev_set_name(pdev, "%sp%d", dname, partno);
-       else
-               dev_set_name(pdev, "%s%d", dname, partno);
-
-       device_initialize(pdev);
-       pdev->class = &block_class;
-       pdev->type = &part_type;
-       pdev->parent = ddev;
-
-       err = blk_alloc_devt(p, &devt);
-       if (err)
-               goto out_free_info;
-       pdev->devt = devt;
-
-       /* delay uevent until 'holders' subdir is created */
-       dev_set_uevent_suppress(pdev, 1);
-       err = device_add(pdev);
-       if (err)
-               goto out_put;
-
-       err = -ENOMEM;
-       p->holder_dir = kobject_create_and_add("holders", &pdev->kobj);
-       if (!p->holder_dir)
-               goto out_del;
-
-       dev_set_uevent_suppress(pdev, 0);
-       if (flags & ADDPART_FLAG_WHOLEDISK) {
-               err = device_create_file(pdev, &dev_attr_whole_disk);
-               if (err)
-                       goto out_del;
-       }
-
-       /* everything is up and running, commence */
-       rcu_assign_pointer(ptbl->part[partno], p);
-
-       /* suppress uevent if the disk suppresses it */
-       if (!dev_get_uevent_suppress(ddev))
-               kobject_uevent(&pdev->kobj, KOBJ_ADD);
-
-       hd_ref_init(p);
-       return p;
-
-out_free_info:
-       free_part_info(p);
-out_free_stats:
-       free_part_stats(p);
-out_free:
-       kfree(p);
-       return ERR_PTR(err);
-out_del:
-       kobject_put(p->holder_dir);
-       device_del(pdev);
-out_put:
-       put_device(pdev);
-       blk_free_devt(devt);
-       return ERR_PTR(err);
-}
-
-static bool disk_unlock_native_capacity(struct gendisk *disk)
-{
-       const struct block_device_operations *bdops = disk->fops;
-
-       if (bdops->unlock_native_capacity &&
-           !(disk->flags & GENHD_FL_NATIVE_CAPACITY)) {
-               printk(KERN_CONT "enabling native capacity\n");
-               bdops->unlock_native_capacity(disk);
-               disk->flags |= GENHD_FL_NATIVE_CAPACITY;
-               return true;
-       } else {
-               printk(KERN_CONT "truncated\n");
-               return false;
-       }
-}
-
-int rescan_partitions(struct gendisk *disk, struct block_device *bdev)
-{
-       struct parsed_partitions *state = NULL;
-       struct disk_part_iter piter;
-       struct hd_struct *part;
-       int p, highest, res;
-rescan:
-       if (state && !IS_ERR(state)) {
-               kfree(state);
-               state = NULL;
-       }
-
-       if (bdev->bd_part_count)
-               return -EBUSY;
-       res = invalidate_partition(disk, 0);
-       if (res)
-               return res;
-
-       disk_part_iter_init(&piter, disk, DISK_PITER_INCL_EMPTY);
-       while ((part = disk_part_iter_next(&piter)))
-               delete_partition(disk, part->partno);
-       disk_part_iter_exit(&piter);
-
-       if (disk->fops->revalidate_disk)
-               disk->fops->revalidate_disk(disk);
-       check_disk_size_change(disk, bdev);
-       bdev->bd_invalidated = 0;
-       if (!get_capacity(disk) || !(state = check_partition(disk, bdev)))
-               return 0;
-       if (IS_ERR(state)) {
-               /*
-                * I/O error reading the partition table.  If any
-                * partition code tried to read beyond EOD, retry
-                * after unlocking native capacity.
-                */
-               if (PTR_ERR(state) == -ENOSPC) {
-                       printk(KERN_WARNING "%s: partition table beyond EOD, ",
-                              disk->disk_name);
-                       if (disk_unlock_native_capacity(disk))
-                               goto rescan;
-               }
-               return -EIO;
-       }
-       /*
-        * If any partition code tried to read beyond EOD, try
-        * unlocking native capacity even if partition table is
-        * successfully read as we could be missing some partitions.
-        */
-       if (state->access_beyond_eod) {
-               printk(KERN_WARNING
-                      "%s: partition table partially beyond EOD, ",
-                      disk->disk_name);
-               if (disk_unlock_native_capacity(disk))
-                       goto rescan;
-       }
-
-       /* tell userspace that the media / partition table may have changed */
-       kobject_uevent(&disk_to_dev(disk)->kobj, KOBJ_CHANGE);
-
-       /* Detect the highest partition number and preallocate
-        * disk->part_tbl.  This is an optimization and not strictly
-        * necessary.
-        */
-       for (p = 1, highest = 0; p < state->limit; p++)
-               if (state->parts[p].size)
-                       highest = p;
-
-       disk_expand_part_tbl(disk, highest);
-
-       /* add partitions */
-       for (p = 1; p < state->limit; p++) {
-               sector_t size, from;
-               struct partition_meta_info *info = NULL;
-
-               size = state->parts[p].size;
-               if (!size)
-                       continue;
-
-               from = state->parts[p].from;
-               if (from >= get_capacity(disk)) {
-                       printk(KERN_WARNING
-                              "%s: p%d start %llu is beyond EOD, ",
-                              disk->disk_name, p, (unsigned long long) from);
-                       if (disk_unlock_native_capacity(disk))
-                               goto rescan;
-                       continue;
-               }
-
-               if (from + size > get_capacity(disk)) {
-                       printk(KERN_WARNING
-                              "%s: p%d size %llu extends beyond EOD, ",
-                              disk->disk_name, p, (unsigned long long) size);
-
-                       if (disk_unlock_native_capacity(disk)) {
-                               /* free state and restart */
-                               goto rescan;
-                       } else {
-                               /*
-                                * we can not ignore partitions of broken tables
-                                * created by for example camera firmware, but
-                                * we limit them to the end of the disk to avoid
-                                * creating invalid block devices
-                                */
-                               size = get_capacity(disk) - from;
-                       }
-               }
-
-               if (state->parts[p].has_info)
-                       info = &state->parts[p].info;
-               part = add_partition(disk, p, from, size,
-                                    state->parts[p].flags,
-                                    &state->parts[p].info);
-               if (IS_ERR(part)) {
-                       printk(KERN_ERR " %s: p%d could not be added: %ld\n",
-                              disk->disk_name, p, -PTR_ERR(part));
-                       continue;
-               }
-#ifdef CONFIG_BLK_DEV_MD
-               if (state->parts[p].flags & ADDPART_FLAG_RAID)
-                       md_autodetect_dev(part_to_dev(part)->devt);
-#endif
-       }
-       kfree(state);
-       return 0;
-}
-
-unsigned char *read_dev_sector(struct block_device *bdev, sector_t n, Sector *p)
-{
-       struct address_space *mapping = bdev->bd_inode->i_mapping;
-       struct page *page;
-
-       page = read_mapping_page(mapping, (pgoff_t)(n >> (PAGE_CACHE_SHIFT-9)),
-                                NULL);
-       if (!IS_ERR(page)) {
-               if (PageError(page))
-                       goto fail;
-               p->v = page;
-               return (unsigned char *)page_address(page) +  ((n & ((1 << (PAGE_CACHE_SHIFT - 9)) - 1)) << 9);
-fail:
-               page_cache_release(page);
-       }
-       p->v = NULL;
-       return NULL;
-}
-
-EXPORT_SYMBOL(read_dev_sector);
index d68bf4d..52b1003 100644 (file)
@@ -22,6 +22,9 @@ struct parsed_partitions {
        char *pp_buf;
 };
 
+struct parsed_partitions *
+check_partition(struct gendisk *, struct block_device *);
+
 static inline void *read_part_sector(struct parsed_partitions *state,
                                     sector_t n, Sector *p)
 {