Change the 9p filesystem to take account of the changes to fscache's
indexing rewrite and reenable caching in 9p.
The following changes have been made:
(1) The fscache_netfs struct is no more, and there's no need to register
the filesystem as a whole.
(2) The session cookie is now an fscache_volume cookie, allocated with
fscache_acquire_volume(). That takes three parameters: a string
representing the "volume" in the index, a string naming the cache to
use (or NULL) and a u64 that conveys coherency metadata for the
volume.
For 9p, I've made it render the volume name string as:
"9p,<devname>,<cachetag>"
where the cachetag is replaced by the aname if it wasn't supplied.
This probably needs rethinking a bit as the aname can have slashes in
it. It might be better to hash the cachetag and use the hash or I
could substitute commas for the slashes or something.
(3) The fscache_cookie_def is no more and needed information is passed
directly to fscache_acquire_cookie(). The cache no longer calls back
into the filesystem, but rather metadata changes are indicated at
other times.
fscache_acquire_cookie() is passed the same keying and coherency
information as before.
(4) The functions to set/reset/flush cookies are removed and
fscache_use_cookie() and fscache_unuse_cookie() are used instead.
fscache_use_cookie() is passed a flag to indicate if the cookie is
opened for writing. fscache_unuse_cookie() is passed updates for the
metadata if we changed it (ie. if the file was opened for writing).
These are called when the file is opened or closed.
(5) wait_on_page_bit[_killable]() is replaced with the specific wait
functions for the bits waited upon.
(6) I've got rid of some of the 9p-specific cache helper functions and
called things like fscache_relinquish_cookie() directly as they'll
optimise away if v9fs_inode_cookie() returns an unconditional NULL
(which will be the case if CONFIG_9P_FSCACHE=n).
(7) v9fs_vfs_setattr() is made to call fscache_resize() to change the size
of the cache object.
Notes:
(A) We should call fscache_invalidate() if we detect that the server's
copy of a file got changed by a third party, but I don't know where to
do that. We don't need to do that when allocating the cookie as we
get a check-and-invalidate when we initially bind to the cache object.
(B) The copy-to-cache-on-writeback side of things will be handled in
separate patch.
Changes
=======
ver #3:
- Canonicalise the cookie key and coherency data to make them
endianness-independent.
ver #2:
- Use gfpflags_allow_blocking() rather than using flag directly.
- fscache_acquire_volume() now returns errors.
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Jeff Layton <jlayton@kernel.org>
Tested-by: Dominique Martinet <asmadeus@codewreck.org>
cc: Eric Van Hensbergen <ericvh@gmail.com>
cc: Latchesar Ionkov <lucho@ionkov.net>
cc: v9fs-developer@lists.sourceforge.net
cc: linux-cachefs@redhat.com
Link: https://lore.kernel.org/r/163819664645.215744.1555314582005286846.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/163906975017.143852.3459573173204394039.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/163967178512.1823006.17377493641569138183.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/164021573143.640689.3977487095697717967.stgit@warthog.procyon.org.uk/
if 9P_FS
config 9P_FSCACHE
bool "Enable 9P client caching support"
- depends on 9P_FS=m && FSCACHE_OLD_API || 9P_FS=y && FSCACHE_OLD_API=y
+ depends on 9P_FS=m && FSCACHE || 9P_FS=y && FSCACHE=y
help
Choose Y here to enable persistent, read-only local
caching support for 9p clients using FS-Cache
#include "v9fs.h"
#include "cache.h"
-#define CACHETAG_LEN 11
-
-struct fscache_netfs v9fs_cache_netfs = {
- .name = "9p",
- .version = 0,
-};
-
-/*
- * v9fs_random_cachetag - Generate a random tag to be associated
- * with a new cache session.
- *
- * The value of jiffies is used for a fairly randomly cache tag.
- */
-
-static
-int v9fs_random_cachetag(struct v9fs_session_info *v9ses)
+int v9fs_cache_session_get_cookie(struct v9fs_session_info *v9ses,
+ const char *dev_name)
{
- v9ses->cachetag = kmalloc(CACHETAG_LEN, GFP_KERNEL);
- if (!v9ses->cachetag)
- return -ENOMEM;
+ struct fscache_volume *vcookie;
+ char *name, *p;
- return scnprintf(v9ses->cachetag, CACHETAG_LEN, "%lu", jiffies);
-}
-
-const struct fscache_cookie_def v9fs_cache_session_index_def = {
- .name = "9P.session",
- .type = FSCACHE_COOKIE_TYPE_INDEX,
-};
+ name = kasprintf(GFP_KERNEL, "9p,%s,%s",
+ dev_name, v9ses->cachetag ?: v9ses->aname);
+ if (!name)
+ return -ENOMEM;
-void v9fs_cache_session_get_cookie(struct v9fs_session_info *v9ses)
-{
- /* If no cache session tag was specified, we generate a random one. */
- if (!v9ses->cachetag) {
- if (v9fs_random_cachetag(v9ses) < 0) {
- v9ses->fscache = NULL;
- kfree(v9ses->cachetag);
- v9ses->cachetag = NULL;
- return;
+ for (p = name; *p; p++)
+ if (*p == '/')
+ *p = ';';
+
+ vcookie = fscache_acquire_volume(name, NULL, NULL, 0);
+ p9_debug(P9_DEBUG_FSC, "session %p get volume %p (%s)\n",
+ v9ses, vcookie, name);
+ if (IS_ERR(vcookie)) {
+ if (vcookie != ERR_PTR(-EBUSY)) {
+ kfree(name);
+ return PTR_ERR(vcookie);
}
+ pr_err("Cache volume key already in use (%s)\n", name);
+ vcookie = NULL;
}
-
- v9ses->fscache = fscache_acquire_cookie(v9fs_cache_netfs.primary_index,
- &v9fs_cache_session_index_def,
- v9ses->cachetag,
- strlen(v9ses->cachetag),
- NULL, 0,
- v9ses, 0, true);
- p9_debug(P9_DEBUG_FSC, "session %p get cookie %p\n",
- v9ses, v9ses->fscache);
-}
-
-void v9fs_cache_session_put_cookie(struct v9fs_session_info *v9ses)
-{
- p9_debug(P9_DEBUG_FSC, "session %p put cookie %p\n",
- v9ses, v9ses->fscache);
- fscache_relinquish_cookie(v9ses->fscache, NULL, false);
- v9ses->fscache = NULL;
-}
-
-static enum
-fscache_checkaux v9fs_cache_inode_check_aux(void *cookie_netfs_data,
- const void *buffer,
- uint16_t buflen,
- loff_t object_size)
-{
- const struct v9fs_inode *v9inode = cookie_netfs_data;
-
- if (buflen != sizeof(v9inode->qid.version))
- return FSCACHE_CHECKAUX_OBSOLETE;
-
- if (memcmp(buffer, &v9inode->qid.version,
- sizeof(v9inode->qid.version)))
- return FSCACHE_CHECKAUX_OBSOLETE;
-
- return FSCACHE_CHECKAUX_OKAY;
+ v9ses->fscache = vcookie;
+ kfree(name);
+ return 0;
}
-const struct fscache_cookie_def v9fs_cache_inode_index_def = {
- .name = "9p.inode",
- .type = FSCACHE_COOKIE_TYPE_DATAFILE,
- .check_aux = v9fs_cache_inode_check_aux,
-};
-
void v9fs_cache_inode_get_cookie(struct inode *inode)
{
struct v9fs_inode *v9inode;
struct v9fs_session_info *v9ses;
+ __le32 version;
+ __le64 path;
if (!S_ISREG(inode->i_mode))
return;
v9inode = V9FS_I(inode);
- if (v9inode->fscache)
+ if (WARN_ON(v9inode->fscache))
return;
+ version = cpu_to_le32(v9inode->qid.version);
+ path = cpu_to_le64(v9inode->qid.path);
v9ses = v9fs_inode2v9ses(inode);
- v9inode->fscache = fscache_acquire_cookie(v9ses->fscache,
- &v9fs_cache_inode_index_def,
- &v9inode->qid.path,
- sizeof(v9inode->qid.path),
- &v9inode->qid.version,
- sizeof(v9inode->qid.version),
- v9inode,
- i_size_read(&v9inode->vfs_inode),
- true);
+ v9inode->fscache =
+ fscache_acquire_cookie(v9fs_session_cache(v9ses),
+ 0,
+ &path, sizeof(path),
+ &version, sizeof(version),
+ i_size_read(&v9inode->vfs_inode));
p9_debug(P9_DEBUG_FSC, "inode %p get cookie %p\n",
inode, v9inode->fscache);
}
-
-void v9fs_cache_inode_put_cookie(struct inode *inode)
-{
- struct v9fs_inode *v9inode = V9FS_I(inode);
-
- if (!v9inode->fscache)
- return;
- p9_debug(P9_DEBUG_FSC, "inode %p put cookie %p\n",
- inode, v9inode->fscache);
-
- fscache_relinquish_cookie(v9inode->fscache, &v9inode->qid.version,
- false);
- v9inode->fscache = NULL;
-}
-
-void v9fs_cache_inode_flush_cookie(struct inode *inode)
-{
- struct v9fs_inode *v9inode = V9FS_I(inode);
-
- if (!v9inode->fscache)
- return;
- p9_debug(P9_DEBUG_FSC, "inode %p flush cookie %p\n",
- inode, v9inode->fscache);
-
- fscache_relinquish_cookie(v9inode->fscache, NULL, true);
- v9inode->fscache = NULL;
-}
-
-void v9fs_cache_inode_set_cookie(struct inode *inode, struct file *filp)
-{
- struct v9fs_inode *v9inode = V9FS_I(inode);
-
- if (!v9inode->fscache)
- return;
-
- mutex_lock(&v9inode->fscache_lock);
-
- if ((filp->f_flags & O_ACCMODE) != O_RDONLY)
- v9fs_cache_inode_flush_cookie(inode);
- else
- v9fs_cache_inode_get_cookie(inode);
-
- mutex_unlock(&v9inode->fscache_lock);
-}
-
-void v9fs_cache_inode_reset_cookie(struct inode *inode)
-{
- struct v9fs_inode *v9inode = V9FS_I(inode);
- struct v9fs_session_info *v9ses;
- struct fscache_cookie *old;
-
- if (!v9inode->fscache)
- return;
-
- old = v9inode->fscache;
-
- mutex_lock(&v9inode->fscache_lock);
- fscache_relinquish_cookie(v9inode->fscache, NULL, true);
-
- v9ses = v9fs_inode2v9ses(inode);
- v9inode->fscache = fscache_acquire_cookie(v9ses->fscache,
- &v9fs_cache_inode_index_def,
- &v9inode->qid.path,
- sizeof(v9inode->qid.path),
- &v9inode->qid.version,
- sizeof(v9inode->qid.version),
- v9inode,
- i_size_read(&v9inode->vfs_inode),
- true);
- p9_debug(P9_DEBUG_FSC, "inode %p revalidating cookie old %p new %p\n",
- inode, old, v9inode->fscache);
-
- mutex_unlock(&v9inode->fscache_lock);
-}
#ifndef _9P_CACHE_H
#define _9P_CACHE_H
-#define FSCACHE_USE_NEW_IO_API
+
#include <linux/fscache.h>
#ifdef CONFIG_9P_FSCACHE
-extern struct fscache_netfs v9fs_cache_netfs;
-extern const struct fscache_cookie_def v9fs_cache_session_index_def;
-extern const struct fscache_cookie_def v9fs_cache_inode_index_def;
-
-extern void v9fs_cache_session_get_cookie(struct v9fs_session_info *v9ses);
-extern void v9fs_cache_session_put_cookie(struct v9fs_session_info *v9ses);
+extern int v9fs_cache_session_get_cookie(struct v9fs_session_info *v9ses,
+ const char *dev_name);
extern void v9fs_cache_inode_get_cookie(struct inode *inode);
-extern void v9fs_cache_inode_put_cookie(struct inode *inode);
-extern void v9fs_cache_inode_flush_cookie(struct inode *inode);
-extern void v9fs_cache_inode_set_cookie(struct inode *inode, struct file *filp);
-extern void v9fs_cache_inode_reset_cookie(struct inode *inode);
-
-extern int __v9fs_cache_register(void);
-extern void __v9fs_cache_unregister(void);
#else /* CONFIG_9P_FSCACHE */
{
}
-static inline void v9fs_cache_inode_put_cookie(struct inode *inode)
-{
-}
-
-static inline void v9fs_cache_inode_set_cookie(struct inode *inode, struct file *file)
-{
-}
-
#endif /* CONFIG_9P_FSCACHE */
#endif /* _9P_CACHE_H */
#ifdef CONFIG_9P_FSCACHE
/* register the session for caching */
- v9fs_cache_session_get_cookie(v9ses);
+ if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) {
+ rc = v9fs_cache_session_get_cookie(v9ses, dev_name);
+ if (rc < 0)
+ goto err_clnt;
+ }
#endif
spin_lock(&v9fs_sessionlist_lock);
list_add(&v9ses->slist, &v9fs_sessionlist);
}
#ifdef CONFIG_9P_FSCACHE
- if (v9ses->fscache)
- v9fs_cache_session_put_cookie(v9ses);
+ fscache_relinquish_volume(v9fs_session_cache(v9ses), NULL, false);
kfree(v9ses->cachetag);
#endif
kfree(v9ses->uname);
ret = v9fs_init_inode_cache();
if (ret < 0)
return ret;
-#ifdef CONFIG_9P_FSCACHE
- ret = fscache_register_netfs(&v9fs_cache_netfs);
- if (ret < 0)
- v9fs_destroy_inode_cache();
-#endif
return ret;
}
static void v9fs_cache_unregister(void)
{
v9fs_destroy_inode_cache();
-#ifdef CONFIG_9P_FSCACHE
- fscache_unregister_netfs(&v9fs_cache_netfs);
-#endif
}
/**
unsigned int cache;
#ifdef CONFIG_9P_FSCACHE
char *cachetag;
- struct fscache_cookie *fscache;
+ struct fscache_volume *fscache;
#endif
char *uname; /* user name to mount as */
struct v9fs_inode {
#ifdef CONFIG_9P_FSCACHE
- struct mutex fscache_lock;
struct fscache_cookie *fscache;
#endif
struct p9_qid qid;
#endif
}
+static inline struct fscache_volume *v9fs_session_cache(struct v9fs_session_info *v9ses)
+{
+#ifdef CONFIG_9P_FSCACHE
+ return v9ses->fscache;
+#else
+ return NULL;
+#endif
+}
+
+
extern int v9fs_show_options(struct seq_file *m, struct dentry *root);
struct p9_fid *v9fs_session_init(struct v9fs_session_info *v9ses,
*/
static bool v9fs_is_cache_enabled(struct inode *inode)
{
- return fscache_cookie_enabled(v9fs_inode_cookie(V9FS_I(inode)));
+ struct fscache_cookie *cookie = v9fs_inode_cookie(V9FS_I(inode));
+
+ return fscache_cookie_enabled(cookie) && cookie->cache_priv;
}
/**
#ifdef CONFIG_9P_FSCACHE
struct fscache_cookie *cookie = v9fs_inode_cookie(V9FS_I(rreq->inode));
- return fscache_begin_read_operation(rreq, cookie);
+ return fscache_begin_read_operation(&rreq->cache_resources, cookie);
#else
return -ENOBUFS;
#endif
return 0;
#ifdef CONFIG_9P_FSCACHE
if (folio_test_fscache(folio)) {
- if (!(gfp & __GFP_DIRECT_RECLAIM) || !(gfp & __GFP_FS))
+ if (!gfpflags_allow_blocking(gfp) || !(gfp & __GFP_FS))
return 0;
folio_wait_fscache(folio);
}
#include <linux/idr.h>
#include <linux/slab.h>
#include <linux/uio.h>
+#include <linux/fscache.h>
#include <net/9p/9p.h>
#include <net/9p/client.h>
int v9fs_dir_release(struct inode *inode, struct file *filp)
{
+ struct v9fs_inode *v9inode = V9FS_I(inode);
struct p9_fid *fid;
+ __le32 version;
+ loff_t i_size;
fid = filp->private_data;
p9_debug(P9_DEBUG_VFS, "inode: %p filp: %p fid: %d\n",
spin_unlock(&inode->i_lock);
p9_client_clunk(fid);
}
+
+ if ((filp->f_mode & FMODE_WRITE)) {
+ version = cpu_to_le32(v9inode->qid.version);
+ i_size = i_size_read(inode);
+ fscache_unuse_cookie(v9fs_inode_cookie(v9inode),
+ &version, &i_size);
+ } else {
+ fscache_unuse_cookie(v9fs_inode_cookie(v9inode), NULL, NULL);
+ }
return 0;
}
}
mutex_unlock(&v9inode->v_mutex);
if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE)
- v9fs_cache_inode_set_cookie(inode, file);
+ fscache_use_cookie(v9fs_inode_cookie(v9inode),
+ file->f_mode & FMODE_WRITE);
v9fs_open_fid_add(inode, fid);
return 0;
out_error:
return NULL;
#ifdef CONFIG_9P_FSCACHE
v9inode->fscache = NULL;
- mutex_init(&v9inode->fscache_lock);
#endif
v9inode->writeback_fid = NULL;
v9inode->cache_validity = 0;
clear_inode(inode);
filemap_fdatawrite(&inode->i_data);
- v9fs_cache_inode_put_cookie(inode);
+ fscache_relinquish_cookie(v9fs_inode_cookie(v9inode), false);
/* clunk the fid stashed in writeback_fid */
if (v9inode->writeback_fid) {
p9_client_clunk(v9inode->writeback_fid);
file->private_data = fid;
if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE)
- v9fs_cache_inode_set_cookie(d_inode(dentry), file);
+ fscache_use_cookie(v9fs_inode_cookie(v9inode),
+ file->f_mode & FMODE_WRITE);
v9fs_open_fid_add(inode, fid);
file->f_mode |= FMODE_CREATED;
struct dentry *dentry, struct iattr *iattr)
{
int retval, use_dentry = 0;
+ struct inode *inode = d_inode(dentry);
+ struct v9fs_inode *v9inode = V9FS_I(inode);
struct v9fs_session_info *v9ses;
struct p9_fid *fid = NULL;
struct p9_wstat wstat;
/* Write all dirty data */
if (d_is_reg(dentry))
- filemap_write_and_wait(d_inode(dentry)->i_mapping);
+ filemap_write_and_wait(inode->i_mapping);
retval = p9_client_wstat(fid, &wstat);
return retval;
if ((iattr->ia_valid & ATTR_SIZE) &&
- iattr->ia_size != i_size_read(d_inode(dentry)))
- truncate_setsize(d_inode(dentry), iattr->ia_size);
+ iattr->ia_size != i_size_read(inode)) {
+ truncate_setsize(inode, iattr->ia_size);
+ fscache_resize_cookie(v9fs_inode_cookie(v9inode), iattr->ia_size);
+ }
- v9fs_invalidate_inode_attr(d_inode(dentry));
+ v9fs_invalidate_inode_attr(inode);
- setattr_copy(&init_user_ns, d_inode(dentry), iattr);
- mark_inode_dirty(d_inode(dentry));
+ setattr_copy(&init_user_ns, inode, iattr);
+ mark_inode_dirty(inode);
return 0;
}
goto err_clunk_old_fid;
file->private_data = ofid;
if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE)
- v9fs_cache_inode_set_cookie(inode, file);
+ fscache_use_cookie(v9fs_inode_cookie(v9inode),
+ file->f_mode & FMODE_WRITE);
v9fs_open_fid_add(inode, ofid);
file->f_mode |= FMODE_CREATED;
out:
projects / platform / kernel / linux-starfive.git / commitdiff