[RFC v2 43/83] Log operation: in-place update log entry

Andiry Xu
2018-03-10T18:34:18Z

To in-place update a log entry, NOVA starts a lite transaction
to journal the log entry, then performs update and commits the transaction.

Signed-off-by: Andiry Xu <jix024@cs.ucsd.edu>
---
fs/nova/inode.h | 12 ++++
fs/nova/log.c | 183 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++
fs/nova/log.h | 9 +++
3 files changed, 204 insertions(+)

diff --git a/fs/nova/inode.h b/fs/nova/inode.h
index 943f77f..6970872 100644
--- a/fs/nova/inode.h
+++ b/fs/nova/inode.h
@@ -5,6 +5,7 @@ struct nova_inode_info_header;
struct nova_inode;

#include "super.h"
+#include "log.h"

enum nova_new_inode_type {
TYPE_CREATE = 0,
@@ -143,6 +144,17 @@ static inline void nova_update_tail(struct nova_inode *pi, u64 new_tail)
NOVA_END_TIMING(update_tail_t, update_time);
}

+static inline void nova_update_inode(struct super_block *sb,
+ struct inode *inode, struct nova_inode *pi,
+ struct nova_inode_update *update)
+{
+ struct nova_inode_info *si = NOVA_I(inode);
+ struct nova_inode_info_header *sih = &si->header;
+
+ sih->log_tail = update->tail;
+ nova_update_tail(pi, update->tail);
+}
+
static inline
struct inode_table *nova_get_inode_table(struct super_block *sb, int cpu)
{
diff --git a/fs/nova/log.c b/fs/nova/log.c
index 4638ccf..c8b7d2e 100644
--- a/fs/nova/log.c
+++ b/fs/nova/log.c
@@ -218,6 +218,35 @@ static int nova_append_log_entry(struct super_block *sb,
return 0;
}

+/* Perform lite transaction to atomically in-place update log entry */
+static int nova_inplace_update_log_entry(struct super_block *sb,
+ struct inode *inode, void *entry,
+ struct nova_log_entry_info *entry_info)
+{
+ struct nova_sb_info *sbi = NOVA_SB(sb);
+ enum nova_entry_type type = entry_info->type;
+ u64 journal_tail;
+ size_t size;
+ int cpu;
+ timing_t update_time;
+
+ NOVA_START_TIMING(update_entry_t, update_time);
+ size = nova_get_log_entry_size(sb, type);
+
+ cpu = smp_processor_id();
+ spin_lock(&sbi->journal_locks[cpu]);
+ journal_tail = nova_create_logentry_transaction(sb, entry, type, cpu);
+ nova_update_log_entry(sb, inode, entry, entry_info);
+
+ PERSISTENT_BARRIER();
+
+ nova_commit_lite_transaction(sb, journal_tail, cpu);
+ spin_unlock(&sbi->journal_locks[cpu]);
+
+ NOVA_END_TIMING(update_entry_t, update_time);
+ return 0;
+}
+
/* Returns new tail after append */
static int nova_append_setattr_entry(struct super_block *sb,
struct nova_inode *pi, struct inode *inode, struct iattr *attr,
@@ -250,6 +279,125 @@ static int nova_append_setattr_entry(struct super_block *sb,
return ret;
}

+static int nova_can_inplace_update_setattr(struct super_block *sb,
+ struct nova_inode_info_header *sih, u64 epoch_id)
+{
+ u64 last_log = 0;
+ struct nova_setattr_logentry *entry = NULL;
+
+ last_log = sih->last_setattr;
+ if (last_log) {
+ entry = (struct nova_setattr_logentry *)nova_get_block(sb,
+ last_log);
+ /* Do not overwrite setsize entry */
+ if (entry->attr & ATTR_SIZE)
+ return 0;
+ if (entry->epoch_id == epoch_id)
+ return 1;
+ }
+
+ return 0;
+}
+
+static int nova_inplace_update_setattr_entry(struct super_block *sb,
+ struct inode *inode, struct nova_inode_info_header *sih,
+ struct iattr *attr, u64 epoch_id)
+{
+ struct nova_setattr_logentry *entry = NULL;
+ struct nova_log_entry_info entry_info;
+ u64 last_log = 0;
+
+ nova_dbgv("%s : Modifying last log entry for inode %lu\n",
+ __func__, inode->i_ino);
+ last_log = sih->last_setattr;
+ entry = (struct nova_setattr_logentry *)nova_get_block(sb,
+ last_log);
+
+ entry_info.type = SET_ATTR;
+ entry_info.attr = attr;
+ entry_info.epoch_id = epoch_id;
+ entry_info.trans_id = sih->trans_id;
+
+ return nova_inplace_update_log_entry(sb, inode, entry,
+ &entry_info);
+}
+
+int nova_handle_setattr_operation(struct super_block *sb, struct inode *inode,
+ struct nova_inode *pi, unsigned int ia_valid, struct iattr *attr,
+ u64 epoch_id)
+{
+ struct nova_inode_info *si = NOVA_I(inode);
+ struct nova_inode_info_header *sih = &si->header;
+ struct nova_inode_update update;
+ u64 last_setattr = 0;
+ int ret;
+
+ if (ia_valid & ATTR_MODE)
+ sih->i_mode = inode->i_mode;
+
+ /*
+ * Let's try to do inplace update.
+ */
+ if (!(ia_valid & ATTR_SIZE) &&
+ nova_can_inplace_update_setattr(sb, sih, epoch_id)) {
+ nova_inplace_update_setattr_entry(sb, inode, sih,
+ attr, epoch_id);
+ } else {
+ /* We are holding inode lock so OK to append the log */
+ nova_dbgv("%s : Appending last log entry for inode ino = %lu\n",
+ __func__, inode->i_ino);
+ update.tail = 0;
+ ret = nova_append_setattr_entry(sb, pi, inode, attr, &update,
+ &last_setattr, epoch_id);
+ if (ret) {
+ nova_dbg("%s: append setattr entry failure\n",
+ __func__);
+ return ret;
+ }
+
+ nova_update_inode(sb, inode, pi, &update);
+ }
+
+ return 0;
+}
+
+static int nova_can_inplace_update_lcentry(struct super_block *sb,
+ struct nova_inode_info_header *sih, u64 epoch_id)
+{
+ u64 last_log = 0;
+ struct nova_link_change_entry *entry = NULL;
+
+ last_log = sih->last_link_change;
+ if (last_log) {
+ entry = (struct nova_link_change_entry *)nova_get_block(sb,
+ last_log);
+ if (entry->epoch_id == epoch_id)
+ return 1;
+ }
+
+ return 0;
+}
+
+static int nova_inplace_update_lcentry(struct super_block *sb,
+ struct inode *inode, struct nova_inode_info_header *sih,
+ u64 epoch_id)
+{
+ struct nova_link_change_entry *entry = NULL;
+ struct nova_log_entry_info entry_info;
+ u64 last_log = 0;
+
+ last_log = sih->last_link_change;
+ entry = (struct nova_link_change_entry *)nova_get_block(sb,
+ last_log);
+
+ entry_info.type = LINK_CHANGE;
+ entry_info.epoch_id = epoch_id;
+ entry_info.trans_id = sih->trans_id;
+
+ return nova_inplace_update_log_entry(sb, inode, entry,
+ &entry_info);
+}
+
/* Returns new tail after append */
int nova_append_link_change_entry(struct super_block *sb,
struct nova_inode *pi, struct inode *inode,
@@ -263,6 +411,15 @@ int nova_append_link_change_entry(struct super_block *sb,

NOVA_START_TIMING(append_link_change_t, append_time);

+ if (nova_can_inplace_update_lcentry(sb, sih, epoch_id)) {
+ nova_inplace_update_lcentry(sb, inode, sih, epoch_id);
+ update->tail = sih->log_tail;
+
+ *old_linkc = 0;
+ sih->trans_id++;
+ goto out;
+ }
+
entry_info.type = LINK_CHANGE;
entry_info.update = update;
entry_info.epoch_id = epoch_id;
@@ -282,6 +439,14 @@ int nova_append_link_change_entry(struct super_block *sb,
return ret;
}

+int nova_inplace_update_write_entry(struct super_block *sb,
+ struct inode *inode, struct nova_file_write_entry *entry,
+ struct nova_log_entry_info *entry_info)
+{
+ return nova_inplace_update_log_entry(sb, inode, entry,
+ entry_info);
+}
+
/*
* Append a nova_file_write_entry to the current nova_inode_log_page.
* blocknr and start_blk are pgoff.
@@ -316,6 +481,24 @@ int nova_append_file_write_entry(struct super_block *sb, struct nova_inode *pi,
return ret;
}

+int nova_inplace_update_dentry(struct super_block *sb,
+ struct inode *dir, struct nova_dentry *dentry, int link_change,
+ u64 epoch_id)
+{
+ struct nova_inode_info *si = NOVA_I(dir);
+ struct nova_inode_info_header *sih = &si->header;
+ struct nova_log_entry_info entry_info;
+
+ entry_info.type = DIR_LOG;
+ entry_info.link_change = link_change;
+ entry_info.epoch_id = epoch_id;
+ entry_info.trans_id = sih->trans_id;
+ entry_info.inplace = 1;
+
+ return nova_inplace_update_log_entry(sb, dir, dentry,
+ &entry_info);
+}
+
int nova_append_dentry(struct super_block *sb, struct nova_inode *pi,
struct inode *dir, struct dentry *dentry, u64 ino,
unsigned short de_len, struct nova_inode_update *update,
diff --git a/fs/nova/log.h b/fs/nova/log.h
index f36f4a3..74891b3 100644
--- a/fs/nova/log.h
+++ b/fs/nova/log.h
@@ -364,12 +364,21 @@ static inline int is_dir_init_entry(struct super_block *sb,
}

+int nova_handle_setattr_operation(struct super_block *sb, struct inode *inode,
+ struct nova_inode *pi, unsigned int ia_valid, struct iattr *attr,
+ u64 epoch_id);
int nova_append_link_change_entry(struct super_block *sb,
struct nova_inode *pi, struct inode *inode,
struct nova_inode_update *update, u64 *old_linkc, u64 epoch_id);
+int nova_inplace_update_write_entry(struct super_block *sb,
+ struct inode *inode, struct nova_file_write_entry *entry,
+ struct nova_log_entry_info *entry_info);
int nova_append_file_write_entry(struct super_block *sb, struct nova_inode *pi,
struct inode *inode, struct nova_file_write_item *item,
struct nova_inode_update *update);
+int nova_inplace_update_dentry(struct super_block *sb,
+ struct inode *dir, struct nova_dentry *dentry, int link_change,
+ u64 epoch_id);
int nova_append_dentry(struct super_block *sb, struct nova_inode *pi,
struct inode *dir, struct dentry *dentry, u64 ino,
unsigned short de_len, struct nova_inode_update *update,
--
2.7.4