2012-10-28 01:53:40

by Namjae Jeon

Subject: [PATCH 4/5] fat: (exportfs) move code to rebuild directory-inode to separate function

From: Namjae Jeon <[email protected]>

Move the logic to rebuild directory inode (when mounted with nostale_ro)
to new function fat_rebuild_parent

Signed-off-by: Namjae Jeon <[email protected]>
Signed-off-by: Ravishankar N <[email protected]>
Signed-off-by: Amit Sahrawat <[email protected]>
---
fs/fat/nfs.c | 71 ++++++++++++++++++++++++++++++++++------------------------
1 file changed, 42 insertions(+), 29 deletions(-)

diff --git a/fs/fat/nfs.c b/fs/fat/nfs.c
index 0abfacf..6e6b233 100644
--- a/fs/fat/nfs.c
+++ b/fs/fat/nfs.c
@@ -312,6 +312,45 @@ static int fat_read_next_clus(struct super_block *sb, int search_clus)
}

/*
+ * Rebuild the parent for a directory that is not connected
+ * to the filesystem root
+ */
+static
+struct inode *fat_rebuild_parent(struct super_block *sb, int parent_logstart)
+{
+ int search_clus, clus_to_match;
+ struct msdos_dir_entry *de;
+ struct inode *parent;
+ struct msdos_sb_info *sbi = MSDOS_SB(sb);
+ sector_t blknr = fat_clus_to_blknr(sbi, parent_logstart);
+ struct buffer_head *parent_bh = sb_bread(sb, blknr);
+
+ if (!parent_bh) {
+ fat_msg(sb, KERN_ERR,
+ "NFS:unable to read cluster of parent directory");
+ return NULL;
+ }
+ de = (struct msdos_dir_entry *) parent_bh->b_data;
+ clus_to_match = fat_get_start(sbi, &de[0]);
+ search_clus = fat_get_start(sbi, &de[1]);
+ if (!search_clus)
+ search_clus = sbi->root_cluster;
+ brelse(parent_bh);
+ do {
+ parent = fat_traverse_cluster(sb,
+ search_clus, clus_to_match);
+ if (IS_ERR(parent) || parent)
+ break;
+ search_clus = fat_read_next_clus(sb, search_clus);
+ if (search_clus < 0)
+ break;
+ } while (search_clus != FAT_ENT_EOF);
+
+ return parent;
+
+
+}
+/*
* Find the parent for a directory that is not currently connected to
* the filesystem root.
*
@@ -320,44 +359,18 @@ static int fat_read_next_clus(struct super_block *sb, int search_clus)
struct dentry *fat_get_parent(struct dentry *child_dir)
{
struct super_block *sb = child_dir->d_sb;
- struct buffer_head *dotdot_bh = NULL, *parent_bh = NULL;
+ struct buffer_head *dotdot_bh = NULL;
struct msdos_dir_entry *de;
struct inode *parent_inode = NULL;
struct msdos_sb_info *sbi = MSDOS_SB(sb);
int parent_logstart;
- int search_clus, clus_to_match;
- sector_t blknr;

if (!fat_get_dotdot_entry(child_dir->d_inode, &dotdot_bh, &de)) {
parent_logstart = fat_get_start(sbi, de);
parent_inode = fat_dget(sb, parent_logstart);
- if (parent_inode || sbi->options.nfs != FAT_NFS_NOSTALE_RO)
- goto out;
- blknr = fat_clus_to_blknr(sbi, parent_logstart);
- parent_bh = sb_bread(sb, blknr);
- if (!parent_bh) {
- fat_msg(sb, KERN_ERR,
- "NFS:unable to read cluster of parent directory");
- goto out;
- }
- de = (struct msdos_dir_entry *) parent_bh->b_data;
- clus_to_match = fat_get_start(sbi, &de[0]);
- search_clus = fat_get_start(sbi, &de[1]);
- if (!search_clus)
- search_clus = sbi->root_cluster;
- brelse(parent_bh);
- do {
- parent_inode = fat_traverse_cluster(sb,
- search_clus, clus_to_match);
- if (IS_ERR(parent_inode) || parent_inode)
- break;
- search_clus = fat_read_next_clus(sb,
- search_clus);
- if (search_clus < 0)
- break;
- } while (search_clus != FAT_ENT_EOF);
+ if (!parent_inode && sbi->options.nfs == FAT_NFS_NOSTALE_RO)
+ parent_inode = fat_rebuild_parent(sb, parent_logstart);
}
-out:
brelse(dotdot_bh);

return d_obtain_alias(parent_inode);
--
1.7.9.5

2012-11-05 12:22:35

by OGAWA Hirofumi

Subject: Re: [PATCH 4/5] fat: (exportfs) move code to rebuild directory-inode to separate function

Namjae Jeon <[email protected]> writes:

> /*
> + * Rebuild the parent for a directory that is not connected
> + * to the filesystem root
> + */
> +static
> +struct inode *fat_rebuild_parent(struct super_block *sb, int parent_logstart)
> +{
> + int search_clus, clus_to_match;
> + struct msdos_dir_entry *de;
> + struct inode *parent;
> + struct msdos_sb_info *sbi = MSDOS_SB(sb);
> + sector_t blknr = fat_clus_to_blknr(sbi, parent_logstart);
> + struct buffer_head *parent_bh = sb_bread(sb, blknr);
> +
> + if (!parent_bh) {
> + fat_msg(sb, KERN_ERR,
> + "NFS:unable to read cluster of parent directory");
> + return NULL;
> + }
> + de = (struct msdos_dir_entry *) parent_bh->b_data;
> + clus_to_match = fat_get_start(sbi, &de[0]);
> + search_clus = fat_get_start(sbi, &de[1]);
> + if (!search_clus)
> + search_clus = sbi->root_cluster;
> + brelse(parent_bh);
> + do {
> + parent = fat_traverse_cluster(sb,
> + search_clus, clus_to_match);
> + if (IS_ERR(parent) || parent)
> + break;
> + search_clus = fat_read_next_clus(sb, search_clus);

fat_read_next_clus() only supports FAT32? Looks strange.
--
OGAWA Hirofumi <[email protected]>