* Updates to directory caching @ 2022-09-23 0:56 Ronnie Sahlberg 2022-09-23 0:56 ` [PATCH 1/2] cifs: find and use the dentry for cached non-root directories also Ronnie Sahlberg 2022-09-23 0:56 ` [PATCH 2/2] cifs: Add a laundromat thread that will timeout any directory leases we have Ronnie Sahlberg 0 siblings, 2 replies; 4+ messages in thread From: Ronnie Sahlberg @ 2022-09-23 0:56 UTC (permalink / raw) To: linux-cifs; +Cc: Steve French Steve, List Small update to the directory caching series. The first patch is an updated to the patch at the tip of your for-next. The patch in for-next does not have the changes Tom suggested. So please replace it with the patch below. The second patch adds a timeout for the leases and a laundromat thread to return the leases when the timeout expired. ^ permalink raw reply [flat|nested] 4+ messages in thread
* [PATCH 1/2] cifs: find and use the dentry for cached non-root directories also 2022-09-23 0:56 Updates to directory caching Ronnie Sahlberg @ 2022-09-23 0:56 ` Ronnie Sahlberg 2022-09-23 0:56 ` [PATCH 2/2] cifs: Add a laundromat thread that will timeout any directory leases we have Ronnie Sahlberg 1 sibling, 0 replies; 4+ messages in thread From: Ronnie Sahlberg @ 2022-09-23 0:56 UTC (permalink / raw) To: linux-cifs; +Cc: Steve French, Ronnie Sahlberg, Steve French This allows us to use cached attributes for the entries in a cached directory for as long as a lease is held on the directory itself. Previously we have always allowed "used cached attributes for 1 second" but this extends this to the lifetime of the lease as well as making the caching safer. Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com> Signed-off-by: Steve French <stfrench@microsoft.com> --- fs/cifs/cached_dir.c | 63 ++++++++++++++++++++++++++++++++++---------- 1 file changed, 49 insertions(+), 14 deletions(-) diff --git a/fs/cifs/cached_dir.c b/fs/cifs/cached_dir.c index 0f62e37b4251..e2f2052dbabf 100644 --- a/fs/cifs/cached_dir.c +++ b/fs/cifs/cached_dir.c @@ -5,6 +5,7 @@ * Copyright (c) 2022, Ronnie Sahlberg <lsahlber@redhat.com> */ +#include <linux/namei.h> #include "cifsglob.h" #include "cifsproto.h" #include "cifs_debug.h" @@ -59,6 +60,44 @@ static struct cached_fid *find_or_create_cached_dir(struct cached_fids *cfids, return cfid; } +static struct dentry * +path_to_dentry(struct cifs_sb_info *cifs_sb, const char *path) +{ + struct dentry *dentry; + const char *s, *p; + char sep; + + sep = CIFS_DIR_SEP(cifs_sb); + dentry = dget(cifs_sb->root); + s = path; + + do { + struct inode *dir = d_inode(dentry); + struct dentry *child; + + if (!S_ISDIR(dir->i_mode)) { + dput(dentry); + dentry = ERR_PTR(-ENOTDIR); + break; + } + + /* skip separators */ + while (*s == sep) + s++; + if (!*s) + break; + p = s++; + /* next separator */ + while (*s && *s != sep) + s++; + + child = lookup_positive_unlocked(p, dentry, s - p); + dput(dentry); + dentry = child; + } while (!IS_ERR(dentry)); + return dentry; +} + /* * Open the and cache a directory handle. * If error then *cfid is not initialized. @@ -86,7 +125,6 @@ int open_cached_dir(unsigned int xid, struct cifs_tcon *tcon, struct cached_fid *cfid; struct cached_fids *cfids; - if (tcon == NULL || tcon->cfids == NULL || tcon->nohandlecache || is_smb1_server(tcon->ses->server)) return -EOPNOTSUPP; @@ -101,13 +139,6 @@ int open_cached_dir(unsigned int xid, struct cifs_tcon *tcon, if (cifs_sb->root == NULL) return -ENOENT; - /* - * TODO: for better caching we need to find and use the dentry also - * for non-root directories. - */ - if (!path[0]) - dentry = cifs_sb->root; - utf16_path = cifs_convert_path_to_utf16(path, cifs_sb); if (!utf16_path) return -ENOMEM; @@ -199,12 +230,6 @@ int open_cached_dir(unsigned int xid, struct cifs_tcon *tcon, oparms.fid->mid = le64_to_cpu(o_rsp->hdr.MessageId); #endif /* CIFS_DEBUG2 */ - cfid->tcon = tcon; - if (dentry) { - cfid->dentry = dentry; - dget(dentry); - } - /* BB TBD check to see if oplock level check can be removed below */ if (o_rsp->OplockLevel != SMB2_OPLOCK_LEVEL_LEASE) { goto oshr_free; } @@ -223,6 +248,16 @@ int open_cached_dir(unsigned int xid, struct cifs_tcon *tcon, &rsp_iov[1], sizeof(struct smb2_file_all_info), (char *)&cfid->file_all_info)) cfid->file_all_info_is_valid = true; + + if (!path[0]) + dentry = dget(cifs_sb->root); + else { + dentry = path_to_dentry(cifs_sb, path); + if (IS_ERR(dentry)) + goto oshr_free; + } + cfid->dentry = dentry; + cfid->tcon = tcon; cfid->time = jiffies; cfid->is_open = true; cfid->has_lease = true; -- 2.35.3 ^ permalink raw reply related [flat|nested] 4+ messages in thread
* [PATCH 2/2] cifs: Add a laundromat thread that will timeout any directory leases we have 2022-09-23 0:56 Updates to directory caching Ronnie Sahlberg 2022-09-23 0:56 ` [PATCH 1/2] cifs: find and use the dentry for cached non-root directories also Ronnie Sahlberg @ 2022-09-23 0:56 ` Ronnie Sahlberg 2022-09-23 5:07 ` Steve French 1 sibling, 1 reply; 4+ messages in thread From: Ronnie Sahlberg @ 2022-09-23 0:56 UTC (permalink / raw) To: linux-cifs; +Cc: Steve French, Ronnie Sahlberg after a timeout of 5 seconds. Later we will add instrumentation to tweak this value. Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com> --- fs/cifs/cached_dir.c | 70 ++++++++++++++++++++++++++++++++++++++++++++ fs/cifs/cached_dir.h | 1 + 2 files changed, 71 insertions(+) diff --git a/fs/cifs/cached_dir.c b/fs/cifs/cached_dir.c index e2f2052dbabf..ffe0dea08b17 100644 --- a/fs/cifs/cached_dir.c +++ b/fs/cifs/cached_dir.c @@ -95,6 +95,7 @@ path_to_dentry(struct cifs_sb_info *cifs_sb, const char *path) dput(dentry); dentry = child; } while (!IS_ERR(dentry)); + return dentry; } @@ -498,6 +499,55 @@ static void free_cached_dir(struct cached_fid *cfid) kfree(cfid); } + + +static int +cifs_cfids_laundromat_thread(void *p) +{ + struct cached_fids *cfids = p; + struct cached_fid *cfid, *q; + struct list_head entry; + + while (!kthread_should_stop()) { + ssleep(1); + INIT_LIST_HEAD(&entry); + if (kthread_should_stop()) + return 0; + spin_lock(&cfids->cfid_list_lock); + list_for_each_entry_safe(cfid, q, &cfids->entries, entry) { + if (time_after(jiffies, cfid->time + HZ * 5)) { + list_del(&cfid->entry); + list_add(&cfid->entry, &entry); + cfids->num_entries--; + } + } + spin_unlock(&cfids->cfid_list_lock); + + list_for_each_entry_safe(cfid, q, &entry, entry) { + cfid->on_list = false; + list_del(&cfid->entry); + /* + * Cancel, and wait for the work to finish in + * case we are racing with it. + */ + cancel_work_sync(&cfid->lease_break); + if (cfid->has_lease) { + /* + * We lease has not yet been cancelled from + * the server so we need to drop the reference. + */ + spin_lock(&cfids->cfid_list_lock); + cfid->has_lease = false; + spin_unlock(&cfids->cfid_list_lock); + kref_put(&cfid->refcount, smb2_close_cached_fid); + } + } + } + + return 0; +} + + struct cached_fids *init_cached_dirs(void) { struct cached_fids *cfids; @@ -507,6 +557,20 @@ struct cached_fids *init_cached_dirs(void) return NULL; spin_lock_init(&cfids->cfid_list_lock); INIT_LIST_HEAD(&cfids->entries); + + /* + * since we're in a cifs function already, we know that + * this will succeed. No need for try_module_get(). + */ + __module_get(THIS_MODULE); + cfids->laundromat = kthread_run(cifs_cfids_laundromat_thread, + cfids, "cifsd-cfid-laundromat"); + if (IS_ERR(cfids->laundromat)) { + cifs_dbg(VFS, "Failed to start cfids laundromat thread.\n"); + kfree(cfids); + module_put(THIS_MODULE); + return NULL; + } return cfids; } @@ -519,6 +583,12 @@ void free_cached_dirs(struct cached_fids *cfids) struct cached_fid *cfid, *q; struct list_head entry; + if (cfids->laundromat) { + kthread_stop(cfids->laundromat); + cfids->laundromat = NULL; + module_put(THIS_MODULE); + } + INIT_LIST_HEAD(&entry); spin_lock(&cfids->cfid_list_lock); list_for_each_entry_safe(cfid, q, &cfids->entries, entry) { diff --git a/fs/cifs/cached_dir.h b/fs/cifs/cached_dir.h index e536304ca2ce..4ab9b10cd098 100644 --- a/fs/cifs/cached_dir.h +++ b/fs/cifs/cached_dir.h @@ -57,6 +57,7 @@ struct cached_fids { spinlock_t cfid_list_lock; int num_entries; struct list_head entries; + struct task_struct *laundromat; }; extern struct cached_fids *init_cached_dirs(void); -- 2.35.3 ^ permalink raw reply related [flat|nested] 4+ messages in thread
* Re: [PATCH 2/2] cifs: Add a laundromat thread that will timeout any directory leases we have 2022-09-23 0:56 ` [PATCH 2/2] cifs: Add a laundromat thread that will timeout any directory leases we have Ronnie Sahlberg @ 2022-09-23 5:07 ` Steve French 0 siblings, 0 replies; 4+ messages in thread From: Steve French @ 2022-09-23 5:07 UTC (permalink / raw) To: Ronnie Sahlberg; +Cc: linux-cifs fixing minor whitespace error and tentatively pushed to cifs-2.6.git for-next pending testing On Thu, Sep 22, 2022 at 7:56 PM Ronnie Sahlberg <lsahlber@redhat.com> wrote: > > after a timeout of 5 seconds. Later we will add instrumentation to tweak this value. > > Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com> > --- > fs/cifs/cached_dir.c | 70 ++++++++++++++++++++++++++++++++++++++++++++ > fs/cifs/cached_dir.h | 1 + > 2 files changed, 71 insertions(+) > > diff --git a/fs/cifs/cached_dir.c b/fs/cifs/cached_dir.c > index e2f2052dbabf..ffe0dea08b17 100644 > --- a/fs/cifs/cached_dir.c > +++ b/fs/cifs/cached_dir.c > @@ -95,6 +95,7 @@ path_to_dentry(struct cifs_sb_info *cifs_sb, const char *path) > dput(dentry); > dentry = child; > } while (!IS_ERR(dentry)); > + > return dentry; > } > > @@ -498,6 +499,55 @@ static void free_cached_dir(struct cached_fid *cfid) > kfree(cfid); > } > > + > + > +static int > +cifs_cfids_laundromat_thread(void *p) > +{ > + struct cached_fids *cfids = p; > + struct cached_fid *cfid, *q; > + struct list_head entry; > + > + while (!kthread_should_stop()) { > + ssleep(1); > + INIT_LIST_HEAD(&entry); > + if (kthread_should_stop()) > + return 0; > + spin_lock(&cfids->cfid_list_lock); > + list_for_each_entry_safe(cfid, q, &cfids->entries, entry) { > + if (time_after(jiffies, cfid->time + HZ * 5)) { > + list_del(&cfid->entry); > + list_add(&cfid->entry, &entry); > + cfids->num_entries--; > + } > + } > + spin_unlock(&cfids->cfid_list_lock); > + > + list_for_each_entry_safe(cfid, q, &entry, entry) { > + cfid->on_list = false; > + list_del(&cfid->entry); > + /* > + * Cancel, and wait for the work to finish in > + * case we are racing with it. > + */ > + cancel_work_sync(&cfid->lease_break); > + if (cfid->has_lease) { > + /* > + * We lease has not yet been cancelled from > + * the server so we need to drop the reference. > + */ > + spin_lock(&cfids->cfid_list_lock); > + cfid->has_lease = false; > + spin_unlock(&cfids->cfid_list_lock); > + kref_put(&cfid->refcount, smb2_close_cached_fid); > + } > + } > + } > + > + return 0; > +} > + > + > struct cached_fids *init_cached_dirs(void) > { > struct cached_fids *cfids; > @@ -507,6 +557,20 @@ struct cached_fids *init_cached_dirs(void) > return NULL; > spin_lock_init(&cfids->cfid_list_lock); > INIT_LIST_HEAD(&cfids->entries); > + > + /* > + * since we're in a cifs function already, we know that > + * this will succeed. No need for try_module_get(). > + */ > + __module_get(THIS_MODULE); > + cfids->laundromat = kthread_run(cifs_cfids_laundromat_thread, > + cfids, "cifsd-cfid-laundromat"); > + if (IS_ERR(cfids->laundromat)) { > + cifs_dbg(VFS, "Failed to start cfids laundromat thread.\n"); > + kfree(cfids); > + module_put(THIS_MODULE); > + return NULL; > + } > return cfids; > } > > @@ -519,6 +583,12 @@ void free_cached_dirs(struct cached_fids *cfids) > struct cached_fid *cfid, *q; > struct list_head entry; > > + if (cfids->laundromat) { > + kthread_stop(cfids->laundromat); > + cfids->laundromat = NULL; > + module_put(THIS_MODULE); > + } > + > INIT_LIST_HEAD(&entry); > spin_lock(&cfids->cfid_list_lock); > list_for_each_entry_safe(cfid, q, &cfids->entries, entry) { > diff --git a/fs/cifs/cached_dir.h b/fs/cifs/cached_dir.h > index e536304ca2ce..4ab9b10cd098 100644 > --- a/fs/cifs/cached_dir.h > +++ b/fs/cifs/cached_dir.h > @@ -57,6 +57,7 @@ struct cached_fids { > spinlock_t cfid_list_lock; > int num_entries; > struct list_head entries; > + struct task_struct *laundromat; > }; > > extern struct cached_fids *init_cached_dirs(void); > -- > 2.35.3 > -- Thanks, Steve ^ permalink raw reply [flat|nested] 4+ messages in thread
end of thread, other threads:[~2022-09-23 5:07 UTC | newest] Thread overview: 4+ messages (download: mbox.gz follow: Atom feed -- links below jump to the message on this page -- 2022-09-23 0:56 Updates to directory caching Ronnie Sahlberg 2022-09-23 0:56 ` [PATCH 1/2] cifs: find and use the dentry for cached non-root directories also Ronnie Sahlberg 2022-09-23 0:56 ` [PATCH 2/2] cifs: Add a laundromat thread that will timeout any directory leases we have Ronnie Sahlberg 2022-09-23 5:07 ` Steve French
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