ext2 reservations

Val's cross-port of the ext3 reservations code into ext2.

[mbligh@mbligh.org: Small type error for printk
[akpm@linux-foundation.org: fix types, sync with ext3]
[mbligh@mbligh.org: Bring ext2 reservations code in line with latest ext3]
[akpm@linux-foundation.org: kill noisy printk]
[akpm@linux-foundation.org: remember to dirty the gdp's block]
[akpm@linux-foundation.org: cross-port the missed 5dea5176e5c32ef9f0d1a41d28427b3bf6881b3a]
[akpm@linux-foundation.org: cross-port e6022603b9aa7d61d20b392e69edcdbbc1789969]
[akpm@linux-foundation.org: Port the omitted 08fb306fe63d98eb86e3b16f4cc21816fa47f18e]
[akpm@linux-foundation.org: Backport the missed 20acaa18d0c002fec180956f87adeb3f11f635a6]
[akpm@linux-foundation.org: fixes]
[cmm@us.ibm.com: fix reservation extension]
[bunk@stusta.de: make ext2_get_blocks() static]
[hugh@veritas.com: fix hang]
[hugh@veritas.com: ext2_new_blocks should reset the reservation window size]
[hugh@veritas.com: ext2 balloc: fix off-by-one against rsv_end]
[hugh@veritas.com: grp_goal 0 is a genuine goal (unlike -1), so ext2_try_to_allocate_with_rsv should treat it as such]
[hugh@veritas.com: rbtree usage cleanup]
[pbadari@us.ibm.com: Fix for ext2 reservation]
[bunk@kernel.org: remove fs/ext2/balloc.c:reserve_blocks()]
[hugh@veritas.com: ext2 balloc: use io_error label]
Cc: "Martin J. Bligh" <mbligh@mbligh.org>
Cc: Valerie Henson <val_henson@linux.intel.com>
Cc: Mingming Cao <cmm@us.ibm.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Badari Pulavarty <pbadari@us.ibm.com>
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 37 insertions, 4 deletions

diff --git a/fs/ext2/super.c b/fs/ext2/super.c
index 51b4c43b97e4..77bd5f9262f9 100644
--- a/fs/ext2/super.c
+++ b/fs/ext2/super.c
@@ -149,6 +149,7 @@ static struct inode *ext2_alloc_inode(struct super_block *sb)
         ei->i_acl = EXT2_ACL_NOT_CACHED;
         ei->i_default_acl = EXT2_ACL_NOT_CACHED;
 #endif
+        ei->i_block_alloc_info = NULL;
         ei->vfs_inode.i_version = 1;
         return &ei->vfs_inode;
 }
@@ -166,6 +167,7 @@ static void init_once(struct kmem_cache * cachep, void *foo)
 #ifdef CONFIG_EXT2_FS_XATTR
         init_rwsem(&ei->xattr_sem);
 #endif
+        mutex_init(&ei->truncate_mutex);
         inode_init_once(&ei->vfs_inode);
 }
 
@@ -188,6 +190,7 @@ static void destroy_inodecache(void)
 
 static void ext2_clear_inode(struct inode *inode)
 {
+        struct ext2_block_alloc_info *rsv = EXT2_I(inode)->i_block_alloc_info;
 #ifdef CONFIG_EXT2_FS_POSIX_ACL
         struct ext2_inode_info *ei = EXT2_I(inode);
 
@@ -200,6 +203,10 @@ static void ext2_clear_inode(struct inode *inode)
                 ei->i_default_acl = EXT2_ACL_NOT_CACHED;
         }
 #endif
+        ext2_discard_reservation(inode);
+        EXT2_I(inode)->i_block_alloc_info = NULL;
+        if (unlikely(rsv))
+                kfree(rsv);
 }
 
 static int ext2_show_options(struct seq_file *seq, struct vfsmount *vfs)
@@ -291,7 +298,6 @@ static const struct super_operations ext2_sops = {
         .destroy_inode  = ext2_destroy_inode,
         .read_inode     = ext2_read_inode,
         .write_inode    = ext2_write_inode,
-        .put_inode      = ext2_put_inode,
         .delete_inode   = ext2_delete_inode,
         .put_super      = ext2_put_super,
         .write_super    = ext2_write_super,
@@ -379,7 +385,7 @@ enum {
         Opt_err_ro, Opt_nouid32, Opt_nocheck, Opt_debug,
         Opt_oldalloc, Opt_orlov, Opt_nobh, Opt_user_xattr, Opt_nouser_xattr,
         Opt_acl, Opt_noacl, Opt_xip, Opt_ignore, Opt_err, Opt_quota,
-        Opt_usrquota, Opt_grpquota
+        Opt_usrquota, Opt_grpquota, Opt_reservation, Opt_noreservation
 };
 
 static match_table_t tokens = {
@@ -411,6 +417,8 @@ static match_table_t tokens = {
         {Opt_ignore, "noquota"},
         {Opt_quota, "quota"},
         {Opt_usrquota, "usrquota"},
+        {Opt_reservation, "reservation"},
+        {Opt_noreservation, "noreservation"},
         {Opt_err, NULL}
 };
 
@@ -543,6 +551,14 @@ static int parse_options (char * options,
                         break;
 #endif
 
+                case Opt_reservation:
+                        set_opt(sbi->s_mount_opt, RESERVATION);
+                        printk("reservations ON\n");
+                        break;
+                case Opt_noreservation:
+                        clear_opt(sbi->s_mount_opt, RESERVATION);
+                        printk("reservations OFF\n");
+                        break;
                 case Opt_ignore:
                         break;
                 default:
@@ -784,6 +800,8 @@ static int ext2_fill_super(struct super_block *sb, void *data, int silent)
         sbi->s_resuid = le16_to_cpu(es->s_def_resuid);
         sbi->s_resgid = le16_to_cpu(es->s_def_resgid);
         
+        set_opt(sbi->s_mount_opt, RESERVATION);
+
         if (!parse_options ((char *) data, sbi))
                 goto failed_mount;
 
@@ -965,6 +983,21 @@ static int ext2_fill_super(struct super_block *sb, void *data, int silent)
         get_random_bytes(&sbi->s_next_generation, sizeof(u32));
         spin_lock_init(&sbi->s_next_gen_lock);
 
+        /* per fileystem reservation list head & lock */
+        spin_lock_init(&sbi->s_rsv_window_lock);
+        sbi->s_rsv_window_root = RB_ROOT;
+        /*
+         * Add a single, static dummy reservation to the start of the
+         * reservation window list --- it gives us a placeholder for
+         * append-at-start-of-list which makes the allocation logic
+         * _much_ simpler.
+         */
+        sbi->s_rsv_window_head.rsv_start = EXT2_RESERVE_WINDOW_NOT_ALLOCATED;
+        sbi->s_rsv_window_head.rsv_end = EXT2_RESERVE_WINDOW_NOT_ALLOCATED;
+        sbi->s_rsv_window_head.rsv_alloc_hit = 0;
+        sbi->s_rsv_window_head.rsv_goal_size = 0;
+        ext2_rsv_window_add(sb, &sbi->s_rsv_window_head);
+
         err = percpu_counter_init(&sbi->s_freeblocks_counter,
                                 ext2_count_free_blocks(sb));
         if (!err) {
@@ -1260,7 +1293,7 @@ static ssize_t ext2_quota_read(struct super_block *sb, int type, char *data,
 
                 tmp_bh.b_state = 0;
                 err = ext2_get_block(inode, blk, &tmp_bh, 0);
-                if (err)
+                if (err < 0)
                         return err;
                 if (!buffer_mapped(&tmp_bh))    /* A hole? */
                         memset(data, 0, tocopy);
@@ -1299,7 +1332,7 @@ static ssize_t ext2_quota_write(struct super_block *sb, int type,
 
                 tmp_bh.b_state = 0;
                 err = ext2_get_block(inode, blk, &tmp_bh, 1);
-                if (err)
+                if (err < 0)
                         goto out;
                 if (offset || tocopy != EXT2_BLOCK_SIZE(sb))
                         bh = sb_bread(sb, tmp_bh.b_blocknr);