struct ocfs2_journal { enum ocfs2_journal_state j_state; /* Journals current state */
journal_t *j_journal; /* The kernels journal type */ struct inode *j_inode; /* Kernel inode pointing to
* this journal */ struct ocfs2_super *j_osb; /* pointer to the super *blockforthenode *we'recurrently *runningon--not *necessarilythesuper *blockfromthenode *whichweusuallyrun *from(recovery,
* etc) */ struct buffer_head *j_bh; /* Journal disk inode block */
atomic_t j_num_trans; /* Number of transactions
* currently in the system. */
spinlock_t j_lock; unsignedlong j_trans_id; struct rw_semaphore j_trans_barrier;
wait_queue_head_t j_checkpointed;
/* both fields protected by j_lock*/ struct list_head j_la_cleanups; struct work_struct j_recovery_work;
};
extern spinlock_t trans_inc_lock;
/* wrap j_trans_id so we never have it equal to zero. */ staticinlineunsignedlong ocfs2_inc_trans_id(struct ocfs2_journal *j)
{ unsignedlong old_id;
spin_lock(&trans_inc_lock);
old_id = j->j_trans_id++; if (unlikely(!j->j_trans_id))
j->j_trans_id = 1;
spin_unlock(&trans_inc_lock); return old_id;
}
/* Used to figure out whether it's safe to drop a metadata lock on an *cachedobject.Returnstrueifalltheobject'schangeshavebeen *checkpointedtodisk.Youshouldbeholdingthespinlockonthe *metadatalockwhilecallingthistobesurethatnobodycantake
* the lock and put it on another transaction. */ staticinlineint ocfs2_ci_fully_checkpointed(struct ocfs2_caching_info *ci)
{ int ret; struct ocfs2_journal *journal =
OCFS2_SB(ocfs2_metadata_cache_get_super(ci))->journal;
spin_lock(&trans_inc_lock);
ret = time_after(journal->j_trans_id, ci->ci_last_trans);
spin_unlock(&trans_inc_lock); return ret;
}
/* convenience function to check if an object backed by struct *ocfs2_caching_infoisstillnew(hasneverhitdisk)Willdoyoua *favorandsetcreated_trans=0whenyou've
* been checkpointed. returns '1' if the ci is still new. */ staticinlineint ocfs2_ci_is_new(struct ocfs2_caching_info *ci)
{ int ret; struct ocfs2_journal *journal =
OCFS2_SB(ocfs2_metadata_cache_get_super(ci))->journal;
spin_lock(&trans_inc_lock);
ret = !(time_after(journal->j_trans_id, ci->ci_created_trans)); if (!ret)
ci->ci_created_trans = 0;
spin_unlock(&trans_inc_lock); return ret;
}
/* Wrapper for inodes so we can check system files */ staticinlineint ocfs2_inode_is_new(struct inode *inode)
{ /* System files are never "new" as they're written out by *mkfs.Thishelpsusearlyduringmount,beforewehavethe
* journal open and j_trans_id could be junk. */ if (OCFS2_I(inode)->ip_flags & OCFS2_INODE_SYSTEM_FILE) return0;
/* Exported only for the journal struct init code in super.c. Do not call. */ void ocfs2_orphan_scan_init(struct ocfs2_super *osb); void ocfs2_orphan_scan_start(struct ocfs2_super *osb); void ocfs2_orphan_scan_stop(struct ocfs2_super *osb);
if (!ocfs2_ci_fully_checkpointed(INODE_CACHE(inode))) { /* WARNING: This only kicks off a single *checkpoint.Ifsomeoneracesyouandaddsmore *metadatatothejournal,youwon'tknow,andwill *windupwaiting*alot*longerthannecessary.Right *nowweonlyusethisinclear_inodesothat's
* OK. */
ocfs2_start_checkpoint(osb);
/* You must always start_trans with a number of buffs > 0, but it's *perfectlylegaltogothroughanentiretransactionwithouthaving
* dirtied any buffers. */
handle_t *ocfs2_start_trans(struct ocfs2_super *osb, int max_buffs); int ocfs2_commit_trans(struct ocfs2_super *osb,
handle_t *handle); int ocfs2_extend_trans(handle_t *handle, int nblocks); int ocfs2_assure_trans_credits(handle_t *handle, int nblocks); int ocfs2_allocate_extend_trans(handle_t *handle, int thresh);
/* Update of a single quota block */ #define OCFS2_QUOTA_BLOCK_UPDATE_CREDITS 1
/* global quotafile inode update, data block */ #define OCFS2_QINFO_WRITE_CREDITS (OCFS2_INODE_UPDATE_CREDITS + \
OCFS2_QUOTA_BLOCK_UPDATE_CREDITS)
#define OCFS2_LOCAL_QINFO_WRITE_CREDITS OCFS2_QUOTA_BLOCK_UPDATE_CREDITS /* *Thetwowritesbelowcanaccidentallyseeglobalinfodirtydue *toset_info()quotactlsomakethempreparedforthewrites.
*/ /* quota data block, global info */ /* Write to local quota file */ #define OCFS2_QWRITE_CREDITS (OCFS2_QINFO_WRITE_CREDITS + \
OCFS2_QUOTA_BLOCK_UPDATE_CREDITS)
/* global quota data block, local quota data block, global quota inode,
* global quota info */ #define OCFS2_QSYNC_CREDITS (OCFS2_QINFO_WRITE_CREDITS + \ 2 * OCFS2_QUOTA_BLOCK_UPDATE_CREDITS)
staticinlineint ocfs2_quota_trans_credits(struct super_block *sb)
{ int credits = 0;
if (OCFS2_HAS_RO_COMPAT_FEATURE(sb, OCFS2_FEATURE_RO_COMPAT_USRQUOTA))
credits += OCFS2_QWRITE_CREDITS; if (OCFS2_HAS_RO_COMPAT_FEATURE(sb, OCFS2_FEATURE_RO_COMPAT_GRPQUOTA))
credits += OCFS2_QWRITE_CREDITS; return credits;
}
/* group extend. inode update and last group update. */ #define OCFS2_GROUP_EXTEND_CREDITS (OCFS2_INODE_UPDATE_CREDITS + 1)
/* group add. inode update and the new group update. */ #define OCFS2_GROUP_ADD_CREDITS (OCFS2_INODE_UPDATE_CREDITS + 1)
/* get one bit out of a suballocator: dinode + group descriptor +
* prev. group desc. if we relink. */ #define OCFS2_SUBALLOC_ALLOC (3)
/* data block for new dir/symlink, allocation of directory block, dx_root
* update for free list */ #define OCFS2_DIR_LINK_ADDITIONAL_CREDITS (1 + OCFS2_SUBALLOC_ALLOC + 1)
/* local alloc metadata change + main bitmap updates */ #define OCFS2_WINDOW_MOVE_CREDITS (OCFS2_INODE_UPDATE_CREDITS \
+ OCFS2_SUBALLOC_ALLOC + OCFS2_SUBALLOC_FREE)
/* used when we don't need an allocation change for a dir extend. One
* for the dinode, one for the new block. */ #define OCFS2_SIMPLE_DIR_EXTEND_CREDITS (2)
/* file update (nlink, etc) + directory mtime/ctime + dir entry block + quota *updateondir+indexleaf+dxrootupdateforfreelist+
* previous dirblock update in the free list */ staticinlineint ocfs2_link_credits(struct super_block *sb)
{ return2 * OCFS2_INODE_UPDATE_CREDITS + 4 +
ocfs2_quota_trans_credits(sb);
}
/* inode + dir inode (if we unlink a dir), + dir entry block + orphan
* dir inode link + dir inode index leaf + dir index root */ staticinlineint ocfs2_unlink_credits(struct super_block *sb)
{ /* The quota update from ocfs2_link_credits is unused here... */ return2 * OCFS2_INODE_UPDATE_CREDITS + 3 + ocfs2_link_credits(sb);
}
/* dinode + orphan dir dinode + inode alloc dinode + orphan dir entry + *inodeallocgroupdescriptor+orphandirindexroot+
* orphan dir index leaf */ #define OCFS2_DELETE_INODE_CREDITS (3 * OCFS2_INODE_UPDATE_CREDITS + 4)
/* dinode + orphan dir dinode + extent tree leaf block + orphan dir entry +
* orphan dir index root + orphan dir index leaf */ #define OCFS2_INODE_ADD_TO_ORPHAN_CREDITS (2 * OCFS2_INODE_UPDATE_CREDITS + 4) #define OCFS2_INODE_DEL_FROM_ORPHAN_CREDITS OCFS2_INODE_ADD_TO_ORPHAN_CREDITS
/* dinode update, old dir dinode update, new dir dinode update, old *dirdirentry,newdirdirentry,direntryupdateforrenaming
* directory + target unlink + 3 x dir index leaves */ staticinlineint ocfs2_rename_credits(struct super_block *sb)
{ return3 * OCFS2_INODE_UPDATE_CREDITS + 6 + ocfs2_unlink_credits(sb);
}
/* we might need to shift tree depth so lets assume an *absoluteworstcaseofcompletefragmentation.Evenwith *that,weonlyneedoneupdateforthedinode,andthen *howevermanymetadatachunksneeded*aremainingsuballoc
* alloc. */
sysfile_bitmap_blocks = 1 +
(OCFS2_SUBALLOC_ALLOC - 1) * ocfs2_extend_meta_needed(root_el);
/* this does not include *new* metadata blocks, which are *accountedforinsysfile_bitmap_blocks.root_el+ *prev.last_eb_blk+blocksalongedgeoftree. *calc_symlink_creditspassesbecausewejustneed1
* credit for the dinode there. */
extent_blocks = 1 + 1 + le16_to_cpu(root_el->l_tree_depth);
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