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authorRussell King <rmk+kernel@armlinux.org.uk>2019-12-09 11:08:39 +0000
committerAl Viro <viro@zeniv.linux.org.uk>2020-01-20 20:12:40 -0500
commit6092b6be304494e311b65935f5e09b510cbd57cc (patch)
treeed8b47c26582d547ec3bdcd65e27f531a96b6b39 /fs/adfs/map.c
parente6160e469f56a23cb69e1dc37aa0d895bf29ac24 (diff)
fs/adfs: map: break up adfs_read_map()
Split up adfs_read_map() into separate helpers to layout the map, read the map, and release the map buffers. Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Diffstat (limited to 'fs/adfs/map.c')
-rw-r--r--fs/adfs/map.c80
1 files changed, 59 insertions, 21 deletions
diff --git a/fs/adfs/map.c b/fs/adfs/map.c
index c322d37e8f91..4b677cd5d015 100644
--- a/fs/adfs/map.c
+++ b/fs/adfs/map.c
@@ -331,12 +331,63 @@ static int adfs_checkmap(struct super_block *sb, struct adfs_discmap *dm)
return crosscheck == 0xff && zonecheck;
}
+/*
+ * Layout the map - the first zone contains a copy of the disc record,
+ * and the last zone must be limited to the size of the filesystem.
+ */
+static void adfs_map_layout(struct adfs_discmap *dm, unsigned int nzones,
+ struct adfs_discrecord *dr)
+{
+ unsigned int zone, zone_size;
+ u64 size;
+
+ zone_size = (8 << dr->log2secsize) - le16_to_cpu(dr->zone_spare);
+
+ dm[0].dm_bh = NULL;
+ dm[0].dm_startblk = 0;
+ dm[0].dm_startbit = ADFS_DR_SIZE_BITS;
+ dm[0].dm_endbit = zone_size;
+
+ for (zone = 1; zone < nzones; zone++) {
+ dm[zone].dm_bh = NULL;
+ dm[zone].dm_startblk = zone * zone_size - ADFS_DR_SIZE_BITS;
+ dm[zone].dm_startbit = 0;
+ dm[zone].dm_endbit = zone_size;
+ }
+
+ size = adfs_disc_size(dr) >> dr->log2bpmb;
+ size -= (nzones - 1) * zone_size - ADFS_DR_SIZE_BITS;
+ dm[nzones - 1].dm_endbit = size;
+}
+
+static int adfs_map_read(struct adfs_discmap *dm, struct super_block *sb,
+ unsigned int map_addr, unsigned int nzones)
+{
+ unsigned int zone;
+
+ for (zone = 0; zone < nzones; zone++) {
+ dm[zone].dm_bh = sb_bread(sb, map_addr + zone);
+ if (!dm[zone].dm_bh)
+ return -EIO;
+ }
+
+ return 0;
+}
+
+static void adfs_map_relse(struct adfs_discmap *dm, unsigned int nzones)
+{
+ unsigned int zone;
+
+ for (zone = 0; zone < nzones; zone++)
+ brelse(dm[zone].dm_bh);
+}
+
struct adfs_discmap *adfs_read_map(struct super_block *sb, struct adfs_discrecord *dr)
{
+ struct adfs_sb_info *asb = ADFS_SB(sb);
struct adfs_discmap *dm;
unsigned int map_addr, zone_size, nzones;
- int i, zone;
- struct adfs_sb_info *asb = ADFS_SB(sb);
+ int ret;
nzones = asb->s_map_size;
zone_size = (8 << dr->log2secsize) - le16_to_cpu(dr->zone_spare);
@@ -352,34 +403,21 @@ struct adfs_discmap *adfs_read_map(struct super_block *sb, struct adfs_discrecor
return ERR_PTR(-ENOMEM);
}
- for (zone = 0; zone < nzones; zone++, map_addr++) {
- dm[zone].dm_startbit = 0;
- dm[zone].dm_endbit = zone_size;
- dm[zone].dm_startblk = zone * zone_size - ADFS_DR_SIZE_BITS;
- dm[zone].dm_bh = sb_bread(sb, map_addr);
+ adfs_map_layout(dm, nzones, dr);
- if (!dm[zone].dm_bh) {
- adfs_error(sb, "unable to read map");
- goto error_free;
- }
+ ret = adfs_map_read(dm, sb, map_addr, nzones);
+ if (ret) {
+ adfs_error(sb, "unable to read map");
+ goto error_free;
}
- /* adjust the limits for the first and last map zones */
- i = zone - 1;
- dm[0].dm_startblk = 0;
- dm[0].dm_startbit = ADFS_DR_SIZE_BITS;
- dm[i].dm_endbit = (adfs_disc_size(dr) >> dr->log2bpmb) +
- (ADFS_DR_SIZE_BITS - i * zone_size);
-
if (adfs_checkmap(sb, dm))
return dm;
adfs_error(sb, "map corrupted");
error_free:
- while (--zone >= 0)
- brelse(dm[zone].dm_bh);
-
+ adfs_map_relse(dm, nzones);
kfree(dm);
return ERR_PTR(-EIO);
}