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Diffstat (limited to 'fs/inode.c')
-rw-r--r--fs/inode.c236
1 files changed, 177 insertions, 59 deletions
diff --git a/fs/inode.c b/fs/inode.c
index 8fefb69e1f84..35fd688168c5 100644
--- a/fs/inode.c
+++ b/fs/inode.c
@@ -16,7 +16,6 @@
#include <linux/fsnotify.h>
#include <linux/mount.h>
#include <linux/posix_acl.h>
-#include <linux/prefetch.h>
#include <linux/buffer_head.h> /* for inode_has_buffers */
#include <linux/ratelimit.h>
#include <linux/list_lru.h>
@@ -752,16 +751,11 @@ EXPORT_SYMBOL_GPL(evict_inodes);
/**
* invalidate_inodes - attempt to free all inodes on a superblock
* @sb: superblock to operate on
- * @kill_dirty: flag to guide handling of dirty inodes
*
- * Attempts to free all inodes for a given superblock. If there were any
- * busy inodes return a non-zero value, else zero.
- * If @kill_dirty is set, discard dirty inodes too, otherwise treat
- * them as busy.
+ * Attempts to free all inodes (including dirty inodes) for a given superblock.
*/
-int invalidate_inodes(struct super_block *sb, bool kill_dirty)
+void invalidate_inodes(struct super_block *sb)
{
- int busy = 0;
struct inode *inode, *next;
LIST_HEAD(dispose);
@@ -773,14 +767,8 @@ again:
spin_unlock(&inode->i_lock);
continue;
}
- if (inode->i_state & I_DIRTY_ALL && !kill_dirty) {
- spin_unlock(&inode->i_lock);
- busy = 1;
- continue;
- }
if (atomic_read(&inode->i_count)) {
spin_unlock(&inode->i_lock);
- busy = 1;
continue;
}
@@ -798,8 +786,6 @@ again:
spin_unlock(&sb->s_inode_list_lock);
dispose_list(&dispose);
-
- return busy;
}
/*
@@ -1041,8 +1027,6 @@ struct inode *new_inode(struct super_block *sb)
{
struct inode *inode;
- spin_lock_prefetch(&sb->s_inode_list_lock);
-
inode = new_inode_pseudo(sb);
if (inode)
inode_sb_list_add(inode);
@@ -1853,6 +1837,7 @@ EXPORT_SYMBOL(bmap);
static int relatime_need_update(struct vfsmount *mnt, struct inode *inode,
struct timespec64 now)
{
+ struct timespec64 ctime;
if (!(mnt->mnt_flags & MNT_RELATIME))
return 1;
@@ -1864,7 +1849,8 @@ static int relatime_need_update(struct vfsmount *mnt, struct inode *inode,
/*
* Is ctime younger than or equal to atime? If yes, update atime:
*/
- if (timespec64_compare(&inode->i_ctime, &inode->i_atime) >= 0)
+ ctime = inode_get_ctime(inode);
+ if (timespec64_compare(&ctime, &inode->i_atime) >= 0)
return 1;
/*
@@ -1879,29 +1865,76 @@ static int relatime_need_update(struct vfsmount *mnt, struct inode *inode,
return 0;
}
-int generic_update_time(struct inode *inode, struct timespec64 *time, int flags)
+/**
+ * inode_update_timestamps - update the timestamps on the inode
+ * @inode: inode to be updated
+ * @flags: S_* flags that needed to be updated
+ *
+ * The update_time function is called when an inode's timestamps need to be
+ * updated for a read or write operation. This function handles updating the
+ * actual timestamps. It's up to the caller to ensure that the inode is marked
+ * dirty appropriately.
+ *
+ * In the case where any of S_MTIME, S_CTIME, or S_VERSION need to be updated,
+ * attempt to update all three of them. S_ATIME updates can be handled
+ * independently of the rest.
+ *
+ * Returns a set of S_* flags indicating which values changed.
+ */
+int inode_update_timestamps(struct inode *inode, int flags)
{
- int dirty_flags = 0;
+ int updated = 0;
+ struct timespec64 now;
- if (flags & (S_ATIME | S_CTIME | S_MTIME)) {
- if (flags & S_ATIME)
- inode->i_atime = *time;
- if (flags & S_CTIME)
- inode->i_ctime = *time;
- if (flags & S_MTIME)
- inode->i_mtime = *time;
-
- if (inode->i_sb->s_flags & SB_LAZYTIME)
- dirty_flags |= I_DIRTY_TIME;
- else
- dirty_flags |= I_DIRTY_SYNC;
+ if (flags & (S_MTIME|S_CTIME|S_VERSION)) {
+ struct timespec64 ctime = inode_get_ctime(inode);
+
+ now = inode_set_ctime_current(inode);
+ if (!timespec64_equal(&now, &ctime))
+ updated |= S_CTIME;
+ if (!timespec64_equal(&now, &inode->i_mtime)) {
+ inode->i_mtime = now;
+ updated |= S_MTIME;
+ }
+ if (IS_I_VERSION(inode) && inode_maybe_inc_iversion(inode, updated))
+ updated |= S_VERSION;
+ } else {
+ now = current_time(inode);
}
- if ((flags & S_VERSION) && inode_maybe_inc_iversion(inode, false))
- dirty_flags |= I_DIRTY_SYNC;
+ if (flags & S_ATIME) {
+ if (!timespec64_equal(&now, &inode->i_atime)) {
+ inode->i_atime = now;
+ updated |= S_ATIME;
+ }
+ }
+ return updated;
+}
+EXPORT_SYMBOL(inode_update_timestamps);
+/**
+ * generic_update_time - update the timestamps on the inode
+ * @inode: inode to be updated
+ * @flags: S_* flags that needed to be updated
+ *
+ * The update_time function is called when an inode's timestamps need to be
+ * updated for a read or write operation. In the case where any of S_MTIME, S_CTIME,
+ * or S_VERSION need to be updated we attempt to update all three of them. S_ATIME
+ * updates can be handled done independently of the rest.
+ *
+ * Returns a S_* mask indicating which fields were updated.
+ */
+int generic_update_time(struct inode *inode, int flags)
+{
+ int updated = inode_update_timestamps(inode, flags);
+ int dirty_flags = 0;
+
+ if (updated & (S_ATIME|S_MTIME|S_CTIME))
+ dirty_flags = inode->i_sb->s_flags & SB_LAZYTIME ? I_DIRTY_TIME : I_DIRTY_SYNC;
+ if (updated & S_VERSION)
+ dirty_flags |= I_DIRTY_SYNC;
__mark_inode_dirty(inode, dirty_flags);
- return 0;
+ return updated;
}
EXPORT_SYMBOL(generic_update_time);
@@ -1909,11 +1942,12 @@ EXPORT_SYMBOL(generic_update_time);
* This does the actual work of updating an inodes time or version. Must have
* had called mnt_want_write() before calling this.
*/
-int inode_update_time(struct inode *inode, struct timespec64 *time, int flags)
+int inode_update_time(struct inode *inode, int flags)
{
if (inode->i_op->update_time)
- return inode->i_op->update_time(inode, time, flags);
- return generic_update_time(inode, time, flags);
+ return inode->i_op->update_time(inode, flags);
+ generic_update_time(inode, flags);
+ return 0;
}
EXPORT_SYMBOL(inode_update_time);
@@ -1965,7 +1999,6 @@ void touch_atime(const struct path *path)
{
struct vfsmount *mnt = path->mnt;
struct inode *inode = d_inode(path->dentry);
- struct timespec64 now;
if (!atime_needs_update(path, inode))
return;
@@ -1984,8 +2017,7 @@ void touch_atime(const struct path *path)
* We may also fail on filesystems that have the ability to make parts
* of the fs read only, e.g. subvolumes in Btrfs.
*/
- now = current_time(inode);
- inode_update_time(inode, &now, S_ATIME);
+ inode_update_time(inode, S_ATIME);
__mnt_drop_write(mnt);
skip_update:
sb_end_write(inode->i_sb);
@@ -2070,18 +2102,63 @@ int file_remove_privs(struct file *file)
}
EXPORT_SYMBOL(file_remove_privs);
-static int inode_needs_update_time(struct inode *inode, struct timespec64 *now)
+/**
+ * current_mgtime - Return FS time (possibly fine-grained)
+ * @inode: inode.
+ *
+ * Return the current time truncated to the time granularity supported by
+ * the fs, as suitable for a ctime/mtime change. If the ctime is flagged
+ * as having been QUERIED, get a fine-grained timestamp.
+ */
+struct timespec64 current_mgtime(struct inode *inode)
+{
+ struct timespec64 now, ctime;
+ atomic_long_t *pnsec = (atomic_long_t *)&inode->__i_ctime.tv_nsec;
+ long nsec = atomic_long_read(pnsec);
+
+ if (nsec & I_CTIME_QUERIED) {
+ ktime_get_real_ts64(&now);
+ return timestamp_truncate(now, inode);
+ }
+
+ ktime_get_coarse_real_ts64(&now);
+ now = timestamp_truncate(now, inode);
+
+ /*
+ * If we've recently fetched a fine-grained timestamp
+ * then the coarse-grained one may still be earlier than the
+ * existing ctime. Just keep the existing value if so.
+ */
+ ctime = inode_get_ctime(inode);
+ if (timespec64_compare(&ctime, &now) > 0)
+ now = ctime;
+
+ return now;
+}
+EXPORT_SYMBOL(current_mgtime);
+
+static struct timespec64 current_ctime(struct inode *inode)
+{
+ if (is_mgtime(inode))
+ return current_mgtime(inode);
+ return current_time(inode);
+}
+
+static int inode_needs_update_time(struct inode *inode)
{
int sync_it = 0;
+ struct timespec64 now = current_ctime(inode);
+ struct timespec64 ctime;
/* First try to exhaust all avenues to not sync */
if (IS_NOCMTIME(inode))
return 0;
- if (!timespec64_equal(&inode->i_mtime, now))
+ if (!timespec64_equal(&inode->i_mtime, &now))
sync_it = S_MTIME;
- if (!timespec64_equal(&inode->i_ctime, now))
+ ctime = inode_get_ctime(inode);
+ if (!timespec64_equal(&ctime, &now))
sync_it |= S_CTIME;
if (IS_I_VERSION(inode) && inode_iversion_need_inc(inode))
@@ -2090,15 +2167,14 @@ static int inode_needs_update_time(struct inode *inode, struct timespec64 *now)
return sync_it;
}
-static int __file_update_time(struct file *file, struct timespec64 *now,
- int sync_mode)
+static int __file_update_time(struct file *file, int sync_mode)
{
int ret = 0;
struct inode *inode = file_inode(file);
/* try to update time settings */
if (!__mnt_want_write_file(file)) {
- ret = inode_update_time(inode, now, sync_mode);
+ ret = inode_update_time(inode, sync_mode);
__mnt_drop_write_file(file);
}
@@ -2123,13 +2199,12 @@ int file_update_time(struct file *file)
{
int ret;
struct inode *inode = file_inode(file);
- struct timespec64 now = current_time(inode);
- ret = inode_needs_update_time(inode, &now);
+ ret = inode_needs_update_time(inode);
if (ret <= 0)
return ret;
- return __file_update_time(file, &now, ret);
+ return __file_update_time(file, ret);
}
EXPORT_SYMBOL(file_update_time);
@@ -2152,7 +2227,6 @@ static int file_modified_flags(struct file *file, int flags)
{
int ret;
struct inode *inode = file_inode(file);
- struct timespec64 now = current_time(inode);
/*
* Clear the security bits if the process is not being run by root.
@@ -2165,13 +2239,13 @@ static int file_modified_flags(struct file *file, int flags)
if (unlikely(file->f_mode & FMODE_NOCMTIME))
return 0;
- ret = inode_needs_update_time(inode, &now);
+ ret = inode_needs_update_time(inode);
if (ret <= 0)
return ret;
if (flags & IOCB_NOWAIT)
return -EAGAIN;
- return __file_update_time(file, &now, ret);
+ return __file_update_time(file, ret);
}
/**
@@ -2491,15 +2565,59 @@ struct timespec64 current_time(struct inode *inode)
struct timespec64 now;
ktime_get_coarse_real_ts64(&now);
+ return timestamp_truncate(now, inode);
+}
+EXPORT_SYMBOL(current_time);
- if (unlikely(!inode->i_sb)) {
- WARN(1, "current_time() called with uninitialized super_block in the inode");
+/**
+ * inode_set_ctime_current - set the ctime to current_time
+ * @inode: inode
+ *
+ * Set the inode->i_ctime to the current value for the inode. Returns
+ * the current value that was assigned to i_ctime.
+ */
+struct timespec64 inode_set_ctime_current(struct inode *inode)
+{
+ struct timespec64 now;
+ struct timespec64 ctime;
+
+ ctime.tv_nsec = READ_ONCE(inode->__i_ctime.tv_nsec);
+ if (!(ctime.tv_nsec & I_CTIME_QUERIED)) {
+ now = current_time(inode);
+
+ /* Just copy it into place if it's not multigrain */
+ if (!is_mgtime(inode)) {
+ inode_set_ctime_to_ts(inode, now);
+ return now;
+ }
+
+ /*
+ * If we've recently updated with a fine-grained timestamp,
+ * then the coarse-grained one may still be earlier than the
+ * existing ctime. Just keep the existing value if so.
+ */
+ ctime.tv_sec = inode->__i_ctime.tv_sec;
+ if (timespec64_compare(&ctime, &now) > 0)
+ return ctime;
+
+ /*
+ * Ctime updates are usually protected by the inode_lock, but
+ * we can still race with someone setting the QUERIED flag.
+ * Try to swap the new nsec value into place. If it's changed
+ * in the interim, then just go with a fine-grained timestamp.
+ */
+ if (cmpxchg(&inode->__i_ctime.tv_nsec, ctime.tv_nsec,
+ now.tv_nsec) != ctime.tv_nsec)
+ goto fine_grained;
+ inode->__i_ctime.tv_sec = now.tv_sec;
return now;
}
-
- return timestamp_truncate(now, inode);
+fine_grained:
+ ktime_get_real_ts64(&now);
+ inode_set_ctime_to_ts(inode, timestamp_truncate(now, inode));
+ return now;
}
-EXPORT_SYMBOL(current_time);
+EXPORT_SYMBOL(inode_set_ctime_current);
/**
* in_group_or_capable - check whether caller is CAP_FSETID privileged