lkml.org 
[lkml]   [2012]   [Jan]   [5]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 12/16] GFS2: split function rgblk_search
Date
From: Bob Peterson <rpeterso@redhat.com>

This patch splits function rgblk_search into a function that finds
blocks to allocate (rgblk_search) and a function that assigns those
blocks (gfs2_alloc_extent).

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@rehat.com>

diff --git a/fs/gfs2/rgrp.c b/fs/gfs2/rgrp.c
index f1d1960..6b6cc09 100644
--- a/fs/gfs2/rgrp.c
+++ b/fs/gfs2/rgrp.c
@@ -65,8 +65,8 @@ static const char valid_change[16] = {
};

static u32 rgblk_search(struct gfs2_rgrpd *rgd, u32 goal,
- unsigned char old_state, bool dinode,
- unsigned int *ndata);
+ unsigned char old_state, bool dinode,
+ struct gfs2_bitmap **rbi);

/**
* gfs2_setbit - Set a bit in the bitmaps
@@ -899,6 +899,11 @@ static int try_rgrp_fit(const struct gfs2_rgrpd *rgd, const struct gfs2_inode *i
return 0;
}

+static inline u32 gfs2_bi2rgd_blk(struct gfs2_bitmap *bi, u32 blk)
+{
+ return (bi->bi_start * GFS2_NBBY) + blk;
+}
+
/**
* try_rgrp_unlink - Look for any unlinked, allocated, but unused inodes
* @rgd: The rgrp
@@ -912,19 +917,20 @@ static void try_rgrp_unlink(struct gfs2_rgrpd *rgd, u64 *last_unlinked, u64 skip
u32 goal = 0, block;
u64 no_addr;
struct gfs2_sbd *sdp = rgd->rd_sbd;
- unsigned int n;
struct gfs2_glock *gl;
struct gfs2_inode *ip;
int error;
int found = 0;
+ struct gfs2_bitmap *bi;

while (goal < rgd->rd_data) {
down_write(&sdp->sd_log_flush_lock);
- n = 1;
- block = rgblk_search(rgd, goal, GFS2_BLKST_UNLINKED, 0, &n);
+ block = rgblk_search(rgd, goal, GFS2_BLKST_UNLINKED, 0, &bi);
up_write(&sdp->sd_log_flush_lock);
if (block == BFITNOENT)
break;
+
+ block = gfs2_bi2rgd_blk(bi, block);
/* rgblk_search can return a block < goal, so we need to
keep it marching forward. */
no_addr = block + rgd->rd_data0;
@@ -1109,38 +1115,35 @@ static unsigned char gfs2_get_block_type(struct gfs2_rgrpd *rgd, u64 block)
}

/**
- * rgblk_search - find a block in @old_state, change allocation
- * state to @new_state
+ * rgblk_search - find a block in @old_state
* @rgd: the resource group descriptor
* @goal: the goal block within the RG (start here to search for avail block)
* @old_state: GFS2_BLKST_XXX the before-allocation state to find
* @dinode: TRUE if the first block we allocate is for a dinode
- * @n: The extent length
+ * @rbi: address of the pointer to the bitmap containing the block found
*
* Walk rgrp's bitmap to find bits that represent a block in @old_state.
- * Add the found bitmap buffer to the transaction.
- * Set the found bits to @new_state to change block's allocation state.
*
* This function never fails, because we wouldn't call it unless we
* know (from reservation results, etc.) that a block is available.
*
- * Scope of @goal and returned block is just within rgrp, not the whole
- * filesystem.
+ * Scope of @goal is just within rgrp, not the whole filesystem.
+ * Scope of @returned block is just within bitmap, not the whole filesystem.
*
- * Returns: the block number allocated
+ * Returns: the block number found relative to the bitmap rbi
*/

static u32 rgblk_search(struct gfs2_rgrpd *rgd, u32 goal,
- unsigned char old_state, bool dinode, unsigned int *n)
+ unsigned char old_state, bool dinode,
+ struct gfs2_bitmap **rbi)
{
struct gfs2_bitmap *bi = NULL;
const u32 length = rgd->rd_length;
u32 blk = BFITNOENT;
unsigned int buf, x;
- const unsigned int elen = *n;
const u8 *buffer = NULL;

- *n = 0;
+ *rbi = NULL;
/* Find bitmap block that contains bits for goal block */
for (buf = 0; buf < length; buf++) {
bi = rgd->rd_bits + buf;
@@ -1187,12 +1190,32 @@ skip:
goal = 0;
}

- if (blk == BFITNOENT)
- return blk;
+ if (blk != BFITNOENT)
+ *rbi = bi;

- if (old_state == GFS2_BLKST_UNLINKED)
- goto out;
+ return blk;
+}

+/**
+ * gfs2_alloc_extent - allocate an extent from a given bitmap
+ * @rgd: the resource group descriptor
+ * @bi: the bitmap within the rgrp
+ * @blk: the block within the bitmap
+ * @dinode: TRUE if the first block we allocate is for a dinode
+ * @n: The extent length
+ *
+ * Add the found bitmap buffer to the transaction.
+ * Set the found bits to @new_state to change block's allocation state.
+ * Returns: starting block number of the extent (fs scope)
+ */
+static u64 gfs2_alloc_extent(struct gfs2_rgrpd *rgd, struct gfs2_bitmap *bi,
+ u32 blk, bool dinode, unsigned int *n)
+{
+ const unsigned int elen = *n;
+ u32 goal;
+ const u8 *buffer = NULL;
+
+ buffer = bi->bi_bh->b_data + bi->bi_offset;
gfs2_trans_add_bh(rgd->rd_gl, bi->bi_bh, 1);
gfs2_setbit(rgd, bi->bi_bh->b_data, bi->bi_clone, bi->bi_offset,
bi, blk, dinode ? GFS2_BLKST_DINODE : GFS2_BLKST_USED);
@@ -1210,8 +1233,9 @@ skip:
bi, goal, GFS2_BLKST_USED);
(*n)++;
}
-out:
- return (bi->bi_start * GFS2_NBBY) + blk;
+ blk = gfs2_bi2rgd_blk(bi, blk);
+ rgd->rd_last_alloc = blk;
+ return rgd->rd_data0 + blk;
}

/**
@@ -1319,6 +1343,7 @@ int gfs2_alloc_blocks(struct gfs2_inode *ip, u64 *bn, unsigned int *ndata,
u32 goal, extlen, blk; /* block, within the rgrp scope */
u64 block; /* block, within the file system scope */
int error;
+ struct gfs2_bitmap *bi;

/* Only happens if there is a bug in gfs2, return something distinctive
* to ensure that it is noticed.
@@ -1333,14 +1358,15 @@ int gfs2_alloc_blocks(struct gfs2_inode *ip, u64 *bn, unsigned int *ndata,
else
goal = rgd->rd_last_alloc;

- blk = rgblk_search(rgd, goal, GFS2_BLKST_FREE, dinode, ndata);
+ blk = rgblk_search(rgd, goal, GFS2_BLKST_FREE, dinode, &bi);

+ *ndata = 0;
/* Since all blocks are reserved in advance, this shouldn't happen */
if (blk == BFITNOENT)
goto rgrp_error;

- rgd->rd_last_alloc = blk;
- block = rgd->rd_data0 + blk;
+ block = gfs2_alloc_extent(rgd, bi, blk, dinode, ndata);
+
if (!dinode) {
ip->i_goal = block + *ndata - 1;
error = gfs2_meta_inode_buffer(ip, &dibh);
--
1.7.4


\
 
 \ /
  Last update: 2012-01-05 13:19    [from the cache]
©2003-2011 Jasper Spaans