rpms/kernel/devel linux-2.6.27-delay-ext4-free-block-cap-check.patch, NONE, 1.1 TODO, 1.33, 1.34 kernel.spec, 1.1090, 1.1091

[Eric Sandeen]

Author: sandeen

Update of /cvs/pkgs/rpms/kernel/devel
In directory cvs1.fedora.phx.redhat.com:/tmp/cvs-serv15617

Modified Files:
	TODO kernel.spec 
Added Files:
	linux-2.6.27-delay-ext4-free-block-cap-check.patch 
Log Message:
* Mon Oct 27 2008 Eric Sandeen <sandeen at redhat.com>
- Delay capable() checks in ext4 until necessary. (#467216)


linux-2.6.27-delay-ext4-free-block-cap-check.patch:

--- NEW FILE linux-2.6.27-delay-ext4-free-block-cap-check.patch ---
diff -u linux-2.6/fs/ext4/balloc.c linux-2.6/fs/ext4/balloc.c
--- linux-2.6/fs/ext4/balloc.c	2008-10-24 15:54:54.225063944 -0500
+++ linux-2.6/fs/ext4/balloc.c	2008-10-24 15:38:52.897001441 -0500
@@ -589,21 +589,23 @@
 	return;
 }
 
-int ext4_claim_free_blocks(struct ext4_sb_info *sbi,
-						s64 nblocks)
+/**
+ * ext4_has_free_blocks()
+ * @sbi:	in-core super block structure.
+ * @nblocks:	number of needed blocks
+ *
+ * Check if filesystem has nblocks free & available for allocation.
+ * On success return 1, return 0 on failure.
+ */
+int ext4_has_free_blocks(struct ext4_sb_info *sbi, s64 nblocks)
 {
-	s64 free_blocks, dirty_blocks;
-	s64 root_blocks = 0;
+	s64 free_blocks, dirty_blocks, root_blocks;
 	struct percpu_counter *fbc = &sbi->s_freeblocks_counter;
 	struct percpu_counter *dbc = &sbi->s_dirtyblocks_counter;
 
 	free_blocks  = percpu_counter_read_positive(fbc);
 	dirty_blocks = percpu_counter_read_positive(dbc);
-
-	if (!capable(CAP_SYS_RESOURCE) &&
-		sbi->s_resuid != current->fsuid &&
-		(sbi->s_resgid == 0 || !in_group_p(sbi->s_resgid)))
-		root_blocks = ext4_r_blocks_count(sbi->s_es);
+	root_blocks = ext4_r_blocks_count(sbi->s_es);
 
 	if (free_blocks - (nblocks + root_blocks + dirty_blocks) <
 						EXT4_FREEBLOCKS_WATERMARK) {
@@ -616,57 +618,32 @@
 		}
 	}
 	/* Check whether we have space after
-	 * accounting for current dirty blocks
+	 * accounting for current dirty blocks & root reserved blocks.
 	 */
-	if (free_blocks < ((root_blocks + nblocks) + dirty_blocks))
-		/* we don't have free space */
-		return -ENOSPC;
+	if (free_blocks >= ((root_blocks + nblocks) + dirty_blocks))
+		return 1;
+
+	/* Hm, nope.  Are (enough) root reserved blocks available? */
+	if (sbi->s_resuid == current->fsuid ||
+	    ((sbi->s_resgid != 0) && in_group_p(sbi->s_resgid)) ||
+	    capable(CAP_SYS_RESOURCE)) {
+		if (free_blocks >= (nblocks + dirty_blocks))
+			return 1;
+	}
 
-	/* Add the blocks to nblocks */
-	percpu_counter_add(dbc, nblocks);
 	return 0;
 }
 
-/**
- * ext4_has_free_blocks()
- * @sbi:	in-core super block structure.
- * @nblocks:	number of neeed blocks
- *
- * Check if filesystem has free blocks available for allocation.
- * Return the number of blocks avaible for allocation for this request
- * On success, return nblocks
- */
-ext4_fsblk_t ext4_has_free_blocks(struct ext4_sb_info *sbi,
+int ext4_claim_free_blocks(struct ext4_sb_info *sbi,
 						s64 nblocks)
 {
-	s64 free_blocks, dirty_blocks;
-	s64 root_blocks = 0;
-	struct percpu_counter *fbc = &sbi->s_freeblocks_counter;
-	struct percpu_counter *dbc = &sbi->s_dirtyblocks_counter;
-
-	free_blocks  = percpu_counter_read_positive(fbc);
-	dirty_blocks = percpu_counter_read_positive(dbc);
-
-	if (!capable(CAP_SYS_RESOURCE) &&
-		sbi->s_resuid != current->fsuid &&
-		(sbi->s_resgid == 0 || !in_group_p(sbi->s_resgid)))
-		root_blocks = ext4_r_blocks_count(sbi->s_es);
-
-	if (free_blocks - (nblocks + root_blocks + dirty_blocks) <
-						EXT4_FREEBLOCKS_WATERMARK) {
-		free_blocks  = percpu_counter_sum(fbc);
-		dirty_blocks = percpu_counter_sum(dbc);
-	}
-	if (free_blocks <= (root_blocks + dirty_blocks))
-		/* we don't have free space */
+	if (ext4_has_free_blocks(sbi, nblocks)) {
+		percpu_counter_add(&sbi->s_dirtyblocks_counter, nblocks);
 		return 0;
-
-	if (free_blocks - (root_blocks + dirty_blocks) < nblocks)
-		return free_blocks - (root_blocks + dirty_blocks);
-	return nblocks;
+	} else
+		return -ENOSPC;
 }
 
-
 /**
  * ext4_should_retry_alloc()
  * @sb:			super block
unchanged:
--- linux-2.6.orig/fs/ext4/ext4.h	2008-10-24 15:32:33.302001208 -0500
+++ linux-2.6/fs/ext4/ext4.h	2008-10-24 15:32:36.077063920 -0500
@@ -1003,8 +1003,7 @@ extern ext4_fsblk_t ext4_new_blocks(hand
 					ext4_lblk_t iblock, ext4_fsblk_t goal,
 					unsigned long *count, int *errp);
 extern int ext4_claim_free_blocks(struct ext4_sb_info *sbi, s64 nblocks);
-extern ext4_fsblk_t ext4_has_free_blocks(struct ext4_sb_info *sbi,
-					 s64 nblocks);
+extern int ext4_has_free_blocks(struct ext4_sb_info *sbi, s64 nblocks);
 extern void ext4_free_blocks(handle_t *handle, struct inode *inode,
 			ext4_fsblk_t block, unsigned long count, int metadata);
 extern void ext4_free_blocks_sb(handle_t *handle, struct super_block *sb,


Index: TODO
===================================================================
RCS file: /cvs/pkgs/rpms/kernel/devel/TODO,v
retrieving revision 1.33
retrieving revision 1.34
diff -u -r1.33 -r1.34
--- TODO	26 Oct 2008 22:58:44 -0000	1.33
+++ TODO	27 Oct 2008 16:46:25 -0000	1.34
@@ -160,6 +160,9 @@
 	in -stable, but reverted in upstream-reverts
         (the ext4 patch queue won't apply if we get this patch from -stable)
 
+linux-2.6.27-delay-ext4-free-block-cap-check.patch
+	In the ext4 queue, will be upstream (for bug #467216)
+
 linux-2.6-x86-avoid-dereferencing-beyond-stack-THREAD_SIZE.patch
 	In mainline and 2.6.26-stable, submitted for 2.6.27-stable.
 


Index: kernel.spec
===================================================================
RCS file: /cvs/pkgs/rpms/kernel/devel/kernel.spec,v
retrieving revision 1.1090
retrieving revision 1.1091
diff -u -r1.1090 -r1.1091
--- kernel.spec	27 Oct 2008 16:41:18 -0000	1.1090
+++ kernel.spec	27 Oct 2008 16:46:25 -0000	1.1091
@@ -708,6 +708,7 @@
 Patch2900: linux-2.6.27-ext4-stable-patch-queue.patch
 Patch2901: linux-2.6.27-fs-disable-fiemap.patch
 Patch2902: linux-2.6.27-ext-dir-corruption-fix.patch
+Patch2903: linux-2.6.27-delay-ext4-free-block-cap-check.patch
 
 # cciss sysfs links are broken
 Patch3000: linux-2.6-blk-cciss-fix-regression-sysfs-symlink-missing.patch
@@ -1134,6 +1135,8 @@
 ApplyPatch linux-2.6.27-fs-disable-fiemap.patch
 # CVE-2008-3528, ext-fs dir corruption
 ApplyPatch linux-2.6.27-ext-dir-corruption-fix.patch
+# Delay capability() checks 'til last in ext4
+ApplyPatch linux-2.6.27-delay-ext4-free-block-cap-check.patch
 
 # xfs
 
@@ -1872,6 +1875,9 @@
 %kernel_variant_files -k vmlinux %{with_kdump} kdump
 
 %changelog
+* Mon Oct 27 2008 Eric Sandeen <sandeen at redhat.com>
+- Delay capable() checks in ext4 until necessary. (#467216)
+
 * Mon Oct 27 2008 Dave Jones <davej at redhat.com>
 - ACPI: Ignore the RESET_REG_SUP bit when using ACPI reset mechanism. (461228)