[GFS2] Fix unlinked file handling

This patch fixes the way we have been dealing with unlinked,
but still open files. It removes all limits (other than memory
for inodes, as per every other filesystem) on numbers of these
which we can support on GFS2. It also means that (like other
fs) its the responsibility of the last process to close the file
to deallocate the storage, rather than the person who did the
unlinking. Note that with GFS2, those two events might take place
on different nodes.

Also there are a number of other changes:

 o We use the Linux inode subsystem as it was intended to be
used, wrt allocating GFS2 inodes
 o The Linux inode cache is now the point which we use for
local enforcement of only holding one copy of the inode in
core at once (previous to this we used the glock layer).
 o We no longer use the unlinked "special" file. We just ignore it
completely. This makes unlinking more efficient.
 o We now use the 4th block allocation state. The previously unused
state is used to track unlinked but still open inodes.
 o gfs2_inoded is no longer needed
 o Several fields are now no longer needed (and removed) from the in
core struct gfs2_inode
 o Several fields are no longer needed (and removed) from the in core
superblock

There are a number of future possible optimisations and clean ups
which have been made possible by this patch.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

1 files changed, 36 insertions, 30 deletions

diff --git a/fs/gfs2/dir.c b/fs/gfs2/dir.c
index 6918a58261e2..b0353884dd7d 100644
--- a/fs/gfs2/dir.c
+++ b/fs/gfs2/dir.c
@@ -113,7 +113,7 @@ static int gfs2_dir_get_existing_buffer(struct gfs2_inode *ip, uint64_t block,
         error = gfs2_meta_read(ip->i_gl, block, DIO_START | DIO_WAIT, &bh);
         if (error)
                 return error;
-        if (gfs2_metatype_check(ip->i_sbd, bh, GFS2_METATYPE_JD)) {
+        if (gfs2_metatype_check(GFS2_SB(&ip->i_inode), bh, GFS2_METATYPE_JD)) {
                 brelse(bh);
                 return -EIO;
         }
@@ -158,7 +158,7 @@ static int gfs2_dir_write_stuffed(struct gfs2_inode *ip, const char *buf,
 static int gfs2_dir_write_data(struct gfs2_inode *ip, const char *buf,
                                uint64_t offset, unsigned int size)
 {
-        struct gfs2_sbd *sdp = ip->i_sbd;
+        struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
         struct buffer_head *dibh;
         uint64_t lblock, dblock;
         uint32_t extlen = 0;
@@ -197,7 +197,7 @@ static int gfs2_dir_write_data(struct gfs2_inode *ip, const char *buf,
 
                 if (!extlen) {
                         new = 1;
-                        error = gfs2_extent_map(ip->i_vnode, lblock, &new,
+                        error = gfs2_extent_map(&ip->i_inode, lblock, &new,
                                                 &dblock, &extlen);
                         if (error)
                                 goto fail;
@@ -277,7 +277,7 @@ static int gfs2_dir_read_stuffed(struct gfs2_inode *ip, char *buf,
 static int gfs2_dir_read_data(struct gfs2_inode *ip, char *buf,
                               uint64_t offset, unsigned int size)
 {
-        struct gfs2_sbd *sdp = ip->i_sbd;
+        struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
         uint64_t lblock, dblock;
         uint32_t extlen = 0;
         unsigned int o;
@@ -314,7 +314,7 @@ static int gfs2_dir_read_data(struct gfs2_inode *ip, char *buf,
 
                 if (!extlen) {
                         new = 0;
-                        error = gfs2_extent_map(ip->i_vnode, lblock, &new,
+                        error = gfs2_extent_map(&ip->i_inode, lblock, &new,
                                                 &dblock, &extlen);
                         if (error)
                                 goto fail;
@@ -534,7 +534,7 @@ static struct gfs2_dirent *gfs2_dirent_scan(struct inode *inode,
         }
 
 consist_inode:
-        gfs2_consist_inode(inode->u.generic_ip);
+        gfs2_consist_inode(GFS2_I(inode));
         return ERR_PTR(-EIO);
 }
 
@@ -556,13 +556,13 @@ static int dirent_first(struct gfs2_inode *dip, struct buffer_head *bh,
         struct gfs2_meta_header *h = (struct gfs2_meta_header *)bh->b_data;
 
         if (be32_to_cpu(h->mh_type) == GFS2_METATYPE_LF) {
-                if (gfs2_meta_check(dip->i_sbd, bh))
+                if (gfs2_meta_check(GFS2_SB(&dip->i_inode), bh))
                         return -EIO;
                 *dent = (struct gfs2_dirent *)(bh->b_data +
                                                sizeof(struct gfs2_leaf));
                 return IS_LEAF;
         } else {
-                if (gfs2_metatype_check(dip->i_sbd, bh, GFS2_METATYPE_DI))
+                if (gfs2_metatype_check(GFS2_SB(&dip->i_inode), bh, GFS2_METATYPE_DI))
                         return -EIO;
                 *dent = (struct gfs2_dirent *)(bh->b_data +
                                                sizeof(struct gfs2_dinode));
@@ -674,7 +674,7 @@ static struct gfs2_dirent *gfs2_init_dirent(struct inode *inode,
                                             const struct qstr *name,
                                             struct buffer_head *bh)
 {
-        struct gfs2_inode *ip = inode->u.generic_ip;
+        struct gfs2_inode *ip = GFS2_I(inode);
         struct gfs2_dirent *ndent;
         unsigned offset = 0, totlen;
 
@@ -707,8 +707,10 @@ static int get_leaf(struct gfs2_inode *dip, uint64_t leaf_no,
         int error;
 
         error = gfs2_meta_read(dip->i_gl, leaf_no, DIO_START | DIO_WAIT, bhp);
-        if (!error && gfs2_metatype_check(dip->i_sbd, *bhp, GFS2_METATYPE_LF))
+        if (!error && gfs2_metatype_check(GFS2_SB(&dip->i_inode), *bhp, GFS2_METATYPE_LF)) {
+                /* printk(KERN_INFO "block num=%llu\n", leaf_no); */
                 error = -EIO;
+        }
 
         return error;
 }
@@ -759,7 +761,7 @@ static struct gfs2_dirent *gfs2_dirent_search(struct inode *inode,
 {
         struct buffer_head *bh;
         struct gfs2_dirent *dent;
-        struct gfs2_inode *ip = inode->u.generic_ip;
+        struct gfs2_inode *ip = GFS2_I(inode);
         int error;
 
         if (ip->i_di.di_flags & GFS2_DIF_EXHASH) {
@@ -771,7 +773,7 @@ static struct gfs2_dirent *gfs2_dirent_search(struct inode *inode,
                         gfs2_consist_inode(ip);
                         return ERR_PTR(-EIO);
                 }
-
+                
                 index = name->hash >> (32 - ip->i_di.di_depth);
                 error = get_first_leaf(ip, index, &bh);
                 if (error)
@@ -786,12 +788,14 @@ static struct gfs2_dirent *gfs2_dirent_search(struct inode *inode,
                         brelse(bh);
                         if (!ln)
                                 break;
+                        
                         error = get_leaf(ip, ln, &bh);
                 } while(!error);
 
                 return error ? ERR_PTR(error) : NULL;
         }
 
+        
         error = gfs2_meta_inode_buffer(ip, &bh);
         if (error)
                 return ERR_PTR(error);
@@ -807,7 +811,7 @@ got_dent:
 
 static struct gfs2_leaf *new_leaf(struct inode *inode, struct buffer_head **pbh, u16 depth)
 {
-        struct gfs2_inode *ip = inode->u.generic_ip;
+        struct gfs2_inode *ip = GFS2_I(inode);
         u64 bn = gfs2_alloc_meta(ip);
         struct buffer_head *bh = gfs2_meta_new(ip->i_gl, bn);
         struct gfs2_leaf *leaf;
@@ -815,6 +819,7 @@ static struct gfs2_leaf *new_leaf(struct inode *inode, struct buffer_head **pbh,
         struct qstr name = { .name = "", .len = 0, .hash = 0 };
         if (!bh)
                 return NULL;
+        
         gfs2_trans_add_bh(ip->i_gl, bh, 1);
         gfs2_metatype_set(bh, GFS2_METATYPE_LF, GFS2_FORMAT_LF);
         leaf = (struct gfs2_leaf *)bh->b_data;
@@ -838,8 +843,8 @@ static struct gfs2_leaf *new_leaf(struct inode *inode, struct buffer_head **pbh,
 
 static int dir_make_exhash(struct inode *inode)
 {
-        struct gfs2_inode *dip = inode->u.generic_ip;
-        struct gfs2_sbd *sdp = dip->i_sbd;
+        struct gfs2_inode *dip = GFS2_I(inode);
+        struct gfs2_sbd *sdp = GFS2_SB(inode);
         struct gfs2_dirent *dent;
         struct qstr args;
         struct buffer_head *bh, *dibh;
@@ -874,7 +879,7 @@ static int dir_make_exhash(struct inode *inode)
         args.len = bh->b_size - sizeof(struct gfs2_dinode) +
                    sizeof(struct gfs2_leaf);
         args.name = bh->b_data;
-        dent = gfs2_dirent_scan(dip->i_vnode, bh->b_data, bh->b_size,
+        dent = gfs2_dirent_scan(&dip->i_inode, bh->b_data, bh->b_size,
                                 gfs2_dirent_last, &args, NULL);
         if (!dent) {
                 brelse(bh);
@@ -933,7 +938,7 @@ static int dir_make_exhash(struct inode *inode)
 
 static int dir_split_leaf(struct inode *inode, const struct qstr *name)
 {
-        struct gfs2_inode *dip = inode->u.generic_ip;
+        struct gfs2_inode *dip = GFS2_I(inode);
         struct buffer_head *nbh, *obh, *dibh;
         struct gfs2_leaf *nleaf, *oleaf;
         struct gfs2_dirent *dent, *prev = NULL, *next = NULL, *new;
@@ -1044,7 +1049,7 @@ static int dir_split_leaf(struct inode *inode, const struct qstr *name)
         oleaf->lf_depth = nleaf->lf_depth;
 
         error = gfs2_meta_inode_buffer(dip, &dibh);
-        if (!gfs2_assert_withdraw(dip->i_sbd, !error)) {
+        if (!gfs2_assert_withdraw(GFS2_SB(&dip->i_inode), !error)) {
                 dip->i_di.di_blocks++;
                 gfs2_dinode_out(&dip->i_di, dibh->b_data);
                 brelse(dibh);
@@ -1073,7 +1078,7 @@ fail_brelse:
 
 static int dir_double_exhash(struct gfs2_inode *dip)
 {
-        struct gfs2_sbd *sdp = dip->i_sbd;
+        struct gfs2_sbd *sdp = GFS2_SB(&dip->i_inode);
         struct buffer_head *dibh;
         uint32_t hsize;
         uint64_t *buf;
@@ -1268,7 +1273,7 @@ static int gfs2_dir_read_leaf(struct inode *inode, u64 *offset, void *opaque,
                               gfs2_filldir_t filldir, int *copied,
                               unsigned *depth, u64 leaf_no)
 {
-        struct gfs2_inode *ip = inode->u.generic_ip;
+        struct gfs2_inode *ip = GFS2_I(inode);
         struct buffer_head *bh;
         struct gfs2_leaf *lf;
         unsigned entries = 0;
@@ -1348,8 +1353,8 @@ out:
 static int dir_e_read(struct inode *inode, uint64_t *offset, void *opaque,
                       gfs2_filldir_t filldir)
 {
-        struct gfs2_inode *dip = inode->u.generic_ip;
-        struct gfs2_sbd *sdp = dip->i_sbd;
+        struct gfs2_inode *dip = GFS2_I(inode);
+        struct gfs2_sbd *sdp = GFS2_SB(inode);
         uint32_t hsize, len = 0;
         uint32_t ht_offset, lp_offset, ht_offset_cur = -1;
         uint32_t hash, index;
@@ -1407,7 +1412,7 @@ out:
 int gfs2_dir_read(struct inode *inode, uint64_t *offset, void *opaque,
                   gfs2_filldir_t filldir)
 {
-        struct gfs2_inode *dip = inode->u.generic_ip;
+        struct gfs2_inode *dip = GFS2_I(inode);
         struct dirent_gather g;
         const struct gfs2_dirent **darr, *dent;
         struct buffer_head *dibh;
@@ -1490,7 +1495,7 @@ int gfs2_dir_search(struct inode *dir, const struct qstr *name,
 static int dir_new_leaf(struct inode *inode, const struct qstr *name)
 {
         struct buffer_head *bh, *obh;
-        struct gfs2_inode *ip = inode->u.generic_ip;
+        struct gfs2_inode *ip = GFS2_I(inode);
         struct gfs2_leaf *leaf, *oleaf;
         int error;
         u32 index;
@@ -1545,7 +1550,7 @@ static int dir_new_leaf(struct inode *inode, const struct qstr *name)
 int gfs2_dir_add(struct inode *inode, const struct qstr *name,
                  const struct gfs2_inum *inum, unsigned type)
 {
-        struct gfs2_inode *ip = inode->u.generic_ip;
+        struct gfs2_inode *ip = GFS2_I(inode);
         struct buffer_head *bh;
         struct gfs2_dirent *dent;
         struct gfs2_leaf *leaf;
@@ -1623,7 +1628,7 @@ int gfs2_dir_del(struct gfs2_inode *dip, const struct qstr *name)
 
         /* Returns _either_ the entry (if its first in block) or the
            previous entry otherwise */
-        dent = gfs2_dirent_search(dip->i_vnode, name, gfs2_dirent_prev, &bh);
+        dent = gfs2_dirent_search(&dip->i_inode, name, gfs2_dirent_prev, &bh);
         if (!dent) {
                 gfs2_consist_inode(dip);
                 return -EIO;
@@ -1659,6 +1664,7 @@ int gfs2_dir_del(struct gfs2_inode *dip, const struct qstr *name)
         dip->i_di.di_mtime = dip->i_di.di_ctime = get_seconds();
         gfs2_dinode_out(&dip->i_di, bh->b_data);
         brelse(bh);
+        mark_inode_dirty(&dip->i_inode);
 
         return error;
 }
@@ -1683,7 +1689,7 @@ int gfs2_dir_mvino(struct gfs2_inode *dip, const struct qstr *filename,
         struct gfs2_dirent *dent;
         int error;
 
-        dent = gfs2_dirent_search(dip->i_vnode, filename, gfs2_dirent_find, &bh);
+        dent = gfs2_dirent_search(&dip->i_inode, filename, gfs2_dirent_find, &bh);
         if (!dent) {
                 gfs2_consist_inode(dip);
                 return -EIO;
@@ -1720,7 +1726,7 @@ int gfs2_dir_mvino(struct gfs2_inode *dip, const struct qstr *filename,
 
 static int foreach_leaf(struct gfs2_inode *dip, leaf_call_t lc, void *data)
 {
-        struct gfs2_sbd *sdp = dip->i_sbd;
+        struct gfs2_sbd *sdp = GFS2_SB(&dip->i_inode);
         struct buffer_head *bh;
         struct gfs2_leaf *leaf;
         uint32_t hsize, len;
@@ -1800,7 +1806,7 @@ static int foreach_leaf(struct gfs2_inode *dip, leaf_call_t lc, void *data)
 static int leaf_dealloc(struct gfs2_inode *dip, uint32_t index, uint32_t len,
                         uint64_t leaf_no, void *data)
 {
-        struct gfs2_sbd *sdp = dip->i_sbd;
+        struct gfs2_sbd *sdp = GFS2_SB(&dip->i_inode);
         struct gfs2_leaf *tmp_leaf;
         struct gfs2_rgrp_list rlist;
         struct buffer_head *bh, *dibh;
@@ -1920,7 +1926,7 @@ static int leaf_dealloc(struct gfs2_inode *dip, uint32_t index, uint32_t len,
 
 int gfs2_dir_exhash_dealloc(struct gfs2_inode *dip)
 {
-        struct gfs2_sbd *sdp = dip->i_sbd;
+        struct gfs2_sbd *sdp = GFS2_SB(&dip->i_inode);
         struct buffer_head *bh;
         int error;