#include <linux/pagemap.h>
#include <linux/export.h>
#include <linux/hid.h>
+#include <linux/module.h>
#include <asm/unaligned.h>
#include <linux/usb/composite.h>
#include <linux/usb/functionfs.h>
+#include "u_fs.h"
+#include "configfs.h"
#define FUNCTIONFS_MAGIC 0xa647361 /* Chosen by a honest dice roll ;) */
-
-/* Debugging ****************************************************************/
-
-#ifdef VERBOSE_DEBUG
-#ifndef pr_vdebug
-# define pr_vdebug pr_debug
-#endif /* pr_vdebug */
-# define ffs_dump_mem(prefix, ptr, len) \
- print_hex_dump_bytes(pr_fmt(prefix ": "), DUMP_PREFIX_NONE, ptr, len)
-#else
-#ifndef pr_vdebug
-# define pr_vdebug(...) do { } while (0)
-#endif /* pr_vdebug */
-# define ffs_dump_mem(prefix, ptr, len) do { } while (0)
-#endif /* VERBOSE_DEBUG */
-
-#define ENTER() pr_vdebug("%s()\n", __func__)
-
-
-/* The data structure and setup file ****************************************/
-
-enum ffs_state {
- /*
- * Waiting for descriptors and strings.
- *
- * In this state no open(2), read(2) or write(2) on epfiles
- * may succeed (which should not be the problem as there
- * should be no such files opened in the first place).
- */
- FFS_READ_DESCRIPTORS,
- FFS_READ_STRINGS,
-
- /*
- * We've got descriptors and strings. We are or have called
- * functionfs_ready_callback(). functionfs_bind() may have
- * been called but we don't know.
- *
- * This is the only state in which operations on epfiles may
- * succeed.
- */
- FFS_ACTIVE,
-
- /*
- * All endpoints have been closed. This state is also set if
- * we encounter an unrecoverable error. The only
- * unrecoverable error is situation when after reading strings
- * from user space we fail to initialise epfiles or
- * functionfs_ready_callback() returns with error (<0).
- *
- * In this state no open(2), read(2) or write(2) (both on ep0
- * as well as epfile) may succeed (at this point epfiles are
- * unlinked and all closed so this is not a problem; ep0 is
- * also closed but ep0 file exists and so open(2) on ep0 must
- * fail).
- */
- FFS_CLOSING
-};
-
-
-enum ffs_setup_state {
- /* There is no setup request pending. */
- FFS_NO_SETUP,
- /*
- * User has read events and there was a setup request event
- * there. The next read/write on ep0 will handle the
- * request.
- */
- FFS_SETUP_PENDING,
- /*
- * There was event pending but before user space handled it
- * some other event was introduced which canceled existing
- * setup. If this state is set read/write on ep0 return
- * -EIDRM. This state is only set when adding event.
- */
- FFS_SETUP_CANCELED
-};
-
-
-
-struct ffs_epfile;
-struct ffs_function;
-
-struct ffs_data {
- struct usb_gadget *gadget;
-
- /*
- * Protect access read/write operations, only one read/write
- * at a time. As a consequence protects ep0req and company.
- * While setup request is being processed (queued) this is
- * held.
- */
- struct mutex mutex;
-
- /*
- * Protect access to endpoint related structures (basically
- * usb_ep_queue(), usb_ep_dequeue(), etc. calls) except for
- * endpoint zero.
- */
- spinlock_t eps_lock;
-
- /*
- * XXX REVISIT do we need our own request? Since we are not
- * handling setup requests immediately user space may be so
- * slow that another setup will be sent to the gadget but this
- * time not to us but another function and then there could be
- * a race. Is that the case? Or maybe we can use cdev->req
- * after all, maybe we just need some spinlock for that?
- */
- struct usb_request *ep0req; /* P: mutex */
- struct completion ep0req_completion; /* P: mutex */
- int ep0req_status; /* P: mutex */
-
- /* reference counter */
- atomic_t ref;
- /* how many files are opened (EP0 and others) */
- atomic_t opened;
-
- /* EP0 state */
- enum ffs_state state;
-
- /*
- * Possible transitions:
- * + FFS_NO_SETUP -> FFS_SETUP_PENDING -- P: ev.waitq.lock
- * happens only in ep0 read which is P: mutex
- * + FFS_SETUP_PENDING -> FFS_NO_SETUP -- P: ev.waitq.lock
- * happens only in ep0 i/o which is P: mutex
- * + FFS_SETUP_PENDING -> FFS_SETUP_CANCELED -- P: ev.waitq.lock
- * + FFS_SETUP_CANCELED -> FFS_NO_SETUP -- cmpxchg
- */
- enum ffs_setup_state setup_state;
-
-#define FFS_SETUP_STATE(ffs) \
- ((enum ffs_setup_state)cmpxchg(&(ffs)->setup_state, \
- FFS_SETUP_CANCELED, FFS_NO_SETUP))
-
- /* Events & such. */
- struct {
- u8 types[4];
- unsigned short count;
- /* XXX REVISIT need to update it in some places, or do we? */
- unsigned short can_stall;
- struct usb_ctrlrequest setup;
-
- wait_queue_head_t waitq;
- } ev; /* the whole structure, P: ev.waitq.lock */
-
- /* Flags */
- unsigned long flags;
-#define FFS_FL_CALL_CLOSED_CALLBACK 0
-#define FFS_FL_BOUND 1
-
- /* Active function */
- struct ffs_function *func;
-
- /*
- * Device name, write once when file system is mounted.
- * Intended for user to read if she wants.
- */
- const char *dev_name;
- /* Private data for our user (ie. gadget). Managed by user. */
- void *private_data;
-
- /* filled by __ffs_data_got_descs() */
- /*
- * Real descriptors are 16 bytes after raw_descs (so you need
- * to skip 16 bytes (ie. ffs->raw_descs + 16) to get to the
- * first full speed descriptor). raw_descs_length and
- * raw_fs_descs_length do not have those 16 bytes added.
- */
- const void *raw_descs;
- unsigned raw_descs_length;
- unsigned raw_fs_descs_length;
- unsigned fs_descs_count;
- unsigned hs_descs_count;
-
- unsigned short strings_count;
- unsigned short interfaces_count;
- unsigned short eps_count;
- unsigned short _pad1;
-
- /* filled by __ffs_data_got_strings() */
- /* ids in stringtabs are set in functionfs_bind() */
- const void *raw_strings;
- struct usb_gadget_strings **stringtabs;
-
- /*
- * File system's super block, write once when file system is
- * mounted.
- */
- struct super_block *sb;
-
- /* File permissions, written once when fs is mounted */
- struct ffs_file_perms {
- umode_t mode;
- kuid_t uid;
- kgid_t gid;
- } file_perms;
-
- /*
- * The endpoint files, filled by ffs_epfiles_create(),
- * destroyed by ffs_epfiles_destroy().
- */
- struct ffs_epfile *epfiles;
-};
+/* Variable Length Array Macros **********************************************/
+#define vla_group(groupname) size_t groupname##__next = 0
+#define vla_group_size(groupname) groupname##__next
+
+#define vla_item(groupname, type, name, n) \
+ size_t groupname##_##name##__offset = ({ \
+ size_t align_mask = __alignof__(type) - 1; \
+ size_t offset = (groupname##__next + align_mask) & ~align_mask;\
+ size_t size = (n) * sizeof(type); \
+ groupname##__next = offset + size; \
+ offset; \
+ })
+
+#define vla_item_with_sz(groupname, type, name, n) \
+ size_t groupname##_##name##__sz = (n) * sizeof(type); \
+ size_t groupname##_##name##__offset = ({ \
+ size_t align_mask = __alignof__(type) - 1; \
+ size_t offset = (groupname##__next + align_mask) & ~align_mask;\
+ size_t size = groupname##_##name##__sz; \
+ groupname##__next = offset + size; \
+ offset; \
+ })
+
+#define vla_ptr(ptr, groupname, name) \
+ ((void *) ((char *)ptr + groupname##_##name##__offset))
/* Reference counter handling */
static void ffs_data_get(struct ffs_data *ffs);
return container_of(f, struct ffs_function, function);
}
-static void ffs_func_free(struct ffs_function *func);
static void ffs_func_eps_disable(struct ffs_function *func);
static int __must_check ffs_func_eps_enable(struct ffs_function *func);
static int ffs_func_bind(struct usb_configuration *,
struct usb_function *);
-static void ffs_func_unbind(struct usb_configuration *,
- struct usb_function *);
static int ffs_func_set_alt(struct usb_function *, unsigned, unsigned);
static void ffs_func_disable(struct usb_function *);
static int ffs_func_setup(struct usb_function *,
const struct file_operations *fops,
struct dentry **dentry_p);
+/* Devices management *******************************************************/
+
+DEFINE_MUTEX(ffs_lock);
+EXPORT_SYMBOL(ffs_lock);
+
+static struct ffs_dev *ffs_find_dev(const char *name);
+static int _ffs_name_dev(struct ffs_dev *dev, const char *name);
+static void *ffs_acquire_dev(const char *dev_name);
+static void ffs_release_dev(struct ffs_data *ffs_data);
+static int ffs_ready(struct ffs_data *ffs);
+static void ffs_closed(struct ffs_data *ffs);
/* Misc helper functions ****************************************************/
ffs->state = FFS_ACTIVE;
mutex_unlock(&ffs->mutex);
- ret = functionfs_ready_callback(ffs);
+ ret = ffs_ready(ffs);
if (unlikely(ret < 0)) {
ffs->state = FFS_CLOSING;
return ret;
char __user *buf, size_t len, int read)
{
struct ffs_epfile *epfile = file->private_data;
+ struct usb_gadget *gadget = epfile->ffs->gadget;
struct ffs_ep *ep;
char *data = NULL;
- ssize_t ret;
+ ssize_t ret, data_len;
int halt;
- goto first_try;
- do {
- spin_unlock_irq(&epfile->ffs->eps_lock);
- mutex_unlock(&epfile->mutex);
+ /* Are we still active? */
+ if (WARN_ON(epfile->ffs->state != FFS_ACTIVE)) {
+ ret = -ENODEV;
+ goto error;
+ }
-first_try:
- /* Are we still active? */
- if (WARN_ON(epfile->ffs->state != FFS_ACTIVE)) {
- ret = -ENODEV;
+ /* Wait for endpoint to be enabled */
+ ep = epfile->ep;
+ if (!ep) {
+ if (file->f_flags & O_NONBLOCK) {
+ ret = -EAGAIN;
goto error;
}
- /* Wait for endpoint to be enabled */
- ep = epfile->ep;
- if (!ep) {
- if (file->f_flags & O_NONBLOCK) {
- ret = -EAGAIN;
- goto error;
- }
-
- if (wait_event_interruptible(epfile->wait,
- (ep = epfile->ep))) {
- ret = -EINTR;
- goto error;
- }
- }
-
- /* Do we halt? */
- halt = !read == !epfile->in;
- if (halt && epfile->isoc) {
- ret = -EINVAL;
+ ret = wait_event_interruptible(epfile->wait, (ep = epfile->ep));
+ if (ret) {
+ ret = -EINTR;
goto error;
}
+ }
- /* Allocate & copy */
- if (!halt && !data) {
- data = kzalloc(len, GFP_KERNEL);
- if (unlikely(!data))
- return -ENOMEM;
+ /* Do we halt? */
+ halt = !read == !epfile->in;
+ if (halt && epfile->isoc) {
+ ret = -EINVAL;
+ goto error;
+ }
- if (!read &&
- unlikely(__copy_from_user(data, buf, len))) {
- ret = -EFAULT;
- goto error;
- }
- }
+ /* Allocate & copy */
+ if (!halt) {
+ /*
+ * Controller may require buffer size to be aligned to
+ * maxpacketsize of an out endpoint.
+ */
+ data_len = read ? usb_ep_align_maybe(gadget, ep->ep, len) : len;
+
+ data = kmalloc(data_len, GFP_KERNEL);
+ if (unlikely(!data))
+ return -ENOMEM;
- /* We will be using request */
- ret = ffs_mutex_lock(&epfile->mutex,
- file->f_flags & O_NONBLOCK);
- if (unlikely(ret))
+ if (!read && unlikely(copy_from_user(data, buf, len))) {
+ ret = -EFAULT;
goto error;
+ }
+ }
- /*
- * We're called from user space, we can use _irq rather then
- * _irqsave
- */
- spin_lock_irq(&epfile->ffs->eps_lock);
+ /* We will be using request */
+ ret = ffs_mutex_lock(&epfile->mutex, file->f_flags & O_NONBLOCK);
+ if (unlikely(ret))
+ goto error;
- /*
- * While we were acquiring mutex endpoint got disabled
- * or changed?
- */
- } while (unlikely(epfile->ep != ep));
+ spin_lock_irq(&epfile->ffs->eps_lock);
- /* Halt */
- if (unlikely(halt)) {
+ if (epfile->ep != ep) {
+ /* In the meantime, endpoint got disabled or changed. */
+ ret = -ESHUTDOWN;
+ spin_unlock_irq(&epfile->ffs->eps_lock);
+ } else if (halt) {
+ /* Halt */
if (likely(epfile->ep == ep) && !WARN_ON(!ep->ep))
usb_ep_set_halt(ep->ep);
spin_unlock_irq(&epfile->ffs->eps_lock);
req->context = &done;
req->complete = ffs_epfile_io_complete;
req->buf = data;
- req->length = len;
+ req->length = data_len;
ret = usb_ep_queue(ep->ep, req, GFP_ATOMIC);
ret = -EINTR;
usb_ep_dequeue(ep->ep, req);
} else {
+ /*
+ * XXX We may end up silently droping data here.
+ * Since data_len (i.e. req->length) may be bigger
+ * than len (after being rounded up to maxpacketsize),
+ * we may end up with more data then user space has
+ * space for.
+ */
ret = ep->status;
if (read && ret > 0 &&
- unlikely(copy_to_user(buf, data, ret)))
+ unlikely(copy_to_user(buf, data,
+ min_t(size_t, ret, len))))
ret = -EFAULT;
}
}
return ERR_PTR(-ENOMEM);
}
- ffs_dev = functionfs_acquire_dev_callback(dev_name);
+ ffs_dev = ffs_acquire_dev(dev_name);
if (IS_ERR(ffs_dev)) {
ffs_data_put(ffs);
return ERR_CAST(ffs_dev);
rv = mount_nodev(t, flags, &data, ffs_sb_fill);
if (IS_ERR(rv) && data.ffs_data) {
- functionfs_release_dev_callback(data.ffs_data);
+ ffs_release_dev(data.ffs_data);
ffs_data_put(data.ffs_data);
}
return rv;
kill_litter_super(sb);
if (sb->s_fs_info) {
- functionfs_release_dev_callback(sb->s_fs_info);
+ ffs_release_dev(sb->s_fs_info);
ffs_data_put(sb->s_fs_info);
}
}
ENTER();
if (test_and_clear_bit(FFS_FL_CALL_CLOSED_CALLBACK, &ffs->flags))
- functionfs_closed_callback(ffs);
+ ffs_closed(ffs);
BUG_ON(ffs->gadget);
kfree(epfiles);
}
-static int functionfs_bind_config(struct usb_composite_dev *cdev,
- struct usb_configuration *c,
- struct ffs_data *ffs)
-{
- struct ffs_function *func;
- int ret;
-
- ENTER();
-
- func = kzalloc(sizeof *func, GFP_KERNEL);
- if (unlikely(!func))
- return -ENOMEM;
-
- func->function.name = "Function FS Gadget";
- func->function.strings = ffs->stringtabs;
-
- func->function.bind = ffs_func_bind;
- func->function.unbind = ffs_func_unbind;
- func->function.set_alt = ffs_func_set_alt;
- func->function.disable = ffs_func_disable;
- func->function.setup = ffs_func_setup;
- func->function.suspend = ffs_func_suspend;
- func->function.resume = ffs_func_resume;
-
- func->conf = c;
- func->gadget = cdev->gadget;
- func->ffs = ffs;
- ffs_data_get(ffs);
-
- ret = usb_add_function(c, &func->function);
- if (unlikely(ret))
- ffs_func_free(func);
-
- return ret;
-}
-
-static void ffs_func_free(struct ffs_function *func)
-{
- struct ffs_ep *ep = func->eps;
- unsigned count = func->ffs->eps_count;
- unsigned long flags;
-
- ENTER();
-
- /* cleanup after autoconfig */
- spin_lock_irqsave(&func->ffs->eps_lock, flags);
- do {
- if (ep->ep && ep->req)
- usb_ep_free_request(ep->ep, ep->req);
- ep->req = NULL;
- ++ep;
- } while (--count);
- spin_unlock_irqrestore(&func->ffs->eps_lock, flags);
-
- ffs_data_put(func->ffs);
-
- kfree(func->eps);
- /*
- * eps and interfaces_nums are allocated in the same chunk so
- * only one free is required. Descriptors are also allocated
- * in the same chunk.
- */
-
- kfree(func);
-}
static void ffs_func_eps_disable(struct ffs_function *func)
{
/* Allocate everything in one chunk so there's less maintenance. */
{
- struct {
- struct usb_gadget_strings *stringtabs[lang_count + 1];
- struct usb_gadget_strings stringtab[lang_count];
- struct usb_string strings[lang_count*(needed_count+1)];
- } *d;
unsigned i = 0;
+ vla_group(d);
+ vla_item(d, struct usb_gadget_strings *, stringtabs,
+ lang_count + 1);
+ vla_item(d, struct usb_gadget_strings, stringtab, lang_count);
+ vla_item(d, struct usb_string, strings,
+ lang_count*(needed_count+1));
+
+ char *vlabuf = kmalloc(vla_group_size(d), GFP_KERNEL);
- d = kmalloc(sizeof *d, GFP_KERNEL);
- if (unlikely(!d)) {
+ if (unlikely(!vlabuf)) {
kfree(_data);
return -ENOMEM;
}
- stringtabs = d->stringtabs;
- t = d->stringtab;
+ /* Initialize the VLA pointers */
+ stringtabs = vla_ptr(vlabuf, d, stringtabs);
+ t = vla_ptr(vlabuf, d, stringtab);
i = lang_count;
do {
*stringtabs++ = t++;
} while (--i);
*stringtabs = NULL;
- stringtabs = d->stringtabs;
- t = d->stringtab;
- s = d->strings;
+ /* stringtabs = vlabuf = d_stringtabs for later kfree */
+ stringtabs = vla_ptr(vlabuf, d, stringtabs);
+ t = vla_ptr(vlabuf, d, stringtab);
+ s = vla_ptr(vlabuf, d, strings);
strings = s;
}
return 0;
}
-static int ffs_func_bind(struct usb_configuration *c,
- struct usb_function *f)
+static inline struct f_fs_opts *ffs_do_functionfs_bind(struct usb_function *f,
+ struct usb_configuration *c)
+{
+ struct ffs_function *func = ffs_func_from_usb(f);
+ struct f_fs_opts *ffs_opts =
+ container_of(f->fi, struct f_fs_opts, func_inst);
+ int ret;
+
+ ENTER();
+
+ /*
+ * Legacy gadget triggers binding in functionfs_ready_callback,
+ * which already uses locking; taking the same lock here would
+ * cause a deadlock.
+ *
+ * Configfs-enabled gadgets however do need ffs_dev_lock.
+ */
+ if (!ffs_opts->no_configfs)
+ ffs_dev_lock();
+ ret = ffs_opts->dev->desc_ready ? 0 : -ENODEV;
+ func->ffs = ffs_opts->dev->ffs_data;
+ if (!ffs_opts->no_configfs)
+ ffs_dev_unlock();
+ if (ret)
+ return ERR_PTR(ret);
+
+ func->conf = c;
+ func->gadget = c->cdev->gadget;
+
+ ffs_data_get(func->ffs);
+
+ /*
+ * in drivers/usb/gadget/configfs.c:configfs_composite_bind()
+ * configurations are bound in sequence with list_for_each_entry,
+ * in each configuration its functions are bound in sequence
+ * with list_for_each_entry, so we assume no race condition
+ * with regard to ffs_opts->bound access
+ */
+ if (!ffs_opts->refcnt) {
+ ret = functionfs_bind(func->ffs, c->cdev);
+ if (ret)
+ return ERR_PTR(ret);
+ }
+ ffs_opts->refcnt++;
+ func->function.strings = func->ffs->stringtabs;
+
+ return ffs_opts;
+}
+
+static int _ffs_func_bind(struct usb_configuration *c,
+ struct usb_function *f)
{
struct ffs_function *func = ffs_func_from_usb(f);
struct ffs_data *ffs = func->ffs;
int ret;
/* Make it a single chunk, less management later on */
- struct {
- struct ffs_ep eps[ffs->eps_count];
- struct usb_descriptor_header
- *fs_descs[full ? ffs->fs_descs_count + 1 : 0];
- struct usb_descriptor_header
- *hs_descs[high ? ffs->hs_descs_count + 1 : 0];
- short inums[ffs->interfaces_count];
- char raw_descs[high ? ffs->raw_descs_length
- : ffs->raw_fs_descs_length];
- } *data;
+ vla_group(d);
+ vla_item_with_sz(d, struct ffs_ep, eps, ffs->eps_count);
+ vla_item_with_sz(d, struct usb_descriptor_header *, fs_descs,
+ full ? ffs->fs_descs_count + 1 : 0);
+ vla_item_with_sz(d, struct usb_descriptor_header *, hs_descs,
+ high ? ffs->hs_descs_count + 1 : 0);
+ vla_item_with_sz(d, short, inums, ffs->interfaces_count);
+ vla_item_with_sz(d, char, raw_descs,
+ high ? ffs->raw_descs_length : ffs->raw_fs_descs_length);
+ char *vlabuf;
ENTER();
if (unlikely(!(full | high)))
return -ENOTSUPP;
- /* Allocate */
- data = kmalloc(sizeof *data, GFP_KERNEL);
- if (unlikely(!data))
+ /* Allocate a single chunk, less management later on */
+ vlabuf = kmalloc(vla_group_size(d), GFP_KERNEL);
+ if (unlikely(!vlabuf))
return -ENOMEM;
/* Zero */
- memset(data->eps, 0, sizeof data->eps);
- memcpy(data->raw_descs, ffs->raw_descs + 16, sizeof data->raw_descs);
- memset(data->inums, 0xff, sizeof data->inums);
- for (ret = ffs->eps_count; ret; --ret)
- data->eps[ret].num = -1;
+ memset(vla_ptr(vlabuf, d, eps), 0, d_eps__sz);
+ memcpy(vla_ptr(vlabuf, d, raw_descs), ffs->raw_descs + 16,
+ d_raw_descs__sz);
+ memset(vla_ptr(vlabuf, d, inums), 0xff, d_inums__sz);
+ for (ret = ffs->eps_count; ret; --ret) {
+ struct ffs_ep *ptr;
+
+ ptr = vla_ptr(vlabuf, d, eps);
+ ptr[ret].num = -1;
+ }
- /* Save pointers */
- func->eps = data->eps;
- func->interfaces_nums = data->inums;
+ /* Save pointers
+ * d_eps == vlabuf, func->eps used to kfree vlabuf later
+ */
+ func->eps = vla_ptr(vlabuf, d, eps);
+ func->interfaces_nums = vla_ptr(vlabuf, d, inums);
/*
* Go through all the endpoint descriptors and allocate
* numbers without worrying that it may be described later on.
*/
if (likely(full)) {
- func->function.fs_descriptors = data->fs_descs;
+ func->function.fs_descriptors = vla_ptr(vlabuf, d, fs_descs);
ret = ffs_do_descs(ffs->fs_descs_count,
- data->raw_descs,
- sizeof data->raw_descs,
+ vla_ptr(vlabuf, d, raw_descs),
+ d_raw_descs__sz,
__ffs_func_bind_do_descs, func);
if (unlikely(ret < 0))
goto error;
}
if (likely(high)) {
- func->function.hs_descriptors = data->hs_descs;
+ func->function.hs_descriptors = vla_ptr(vlabuf, d, hs_descs);
ret = ffs_do_descs(ffs->hs_descs_count,
- data->raw_descs + ret,
- (sizeof data->raw_descs) - ret,
+ vla_ptr(vlabuf, d, raw_descs) + ret,
+ d_raw_descs__sz - ret,
__ffs_func_bind_do_descs, func);
if (unlikely(ret < 0))
goto error;
*/
ret = ffs_do_descs(ffs->fs_descs_count +
(high ? ffs->hs_descs_count : 0),
- data->raw_descs, sizeof data->raw_descs,
+ vla_ptr(vlabuf, d, raw_descs), d_raw_descs__sz,
__ffs_func_bind_do_nums, func);
if (unlikely(ret < 0))
goto error;
return ret;
}
-
-/* Other USB function hooks *************************************************/
-
-static void ffs_func_unbind(struct usb_configuration *c,
- struct usb_function *f)
+static int ffs_func_bind(struct usb_configuration *c,
+ struct usb_function *f)
{
- struct ffs_function *func = ffs_func_from_usb(f);
- struct ffs_data *ffs = func->ffs;
+ struct f_fs_opts *ffs_opts = ffs_do_functionfs_bind(f, c);
- ENTER();
+ if (IS_ERR(ffs_opts))
+ return PTR_ERR(ffs_opts);
- if (ffs->func == func) {
- ffs_func_eps_disable(func);
- ffs->func = NULL;
- }
+ return _ffs_func_bind(c, f);
+}
- ffs_event_add(ffs, FUNCTIONFS_UNBIND);
- ffs_func_free(func);
-}
+/* Other USB function hooks *************************************************/
static int ffs_func_set_alt(struct usb_function *f,
unsigned interface, unsigned alt)
}
+/* Devices management *******************************************************/
+
+static LIST_HEAD(ffs_devices);
+
+static struct ffs_dev *_ffs_find_dev(const char *name)
+{
+ struct ffs_dev *dev;
+
+ list_for_each_entry(dev, &ffs_devices, entry) {
+ if (!dev->name || !name)
+ continue;
+ if (strcmp(dev->name, name) == 0)
+ return dev;
+ }
+
+ return NULL;
+}
+
+/*
+ * ffs_lock must be taken by the caller of this function
+ */
+static struct ffs_dev *ffs_get_single_dev(void)
+{
+ struct ffs_dev *dev;
+
+ if (list_is_singular(&ffs_devices)) {
+ dev = list_first_entry(&ffs_devices, struct ffs_dev, entry);
+ if (dev->single)
+ return dev;
+ }
+
+ return NULL;
+}
+
+/*
+ * ffs_lock must be taken by the caller of this function
+ */
+static struct ffs_dev *ffs_find_dev(const char *name)
+{
+ struct ffs_dev *dev;
+
+ dev = ffs_get_single_dev();
+ if (dev)
+ return dev;
+
+ return _ffs_find_dev(name);
+}
+
+/* Configfs support *********************************************************/
+
+static inline struct f_fs_opts *to_ffs_opts(struct config_item *item)
+{
+ return container_of(to_config_group(item), struct f_fs_opts,
+ func_inst.group);
+}
+
+static void ffs_attr_release(struct config_item *item)
+{
+ struct f_fs_opts *opts = to_ffs_opts(item);
+
+ usb_put_function_instance(&opts->func_inst);
+}
+
+static struct configfs_item_operations ffs_item_ops = {
+ .release = ffs_attr_release,
+};
+
+static struct config_item_type ffs_func_type = {
+ .ct_item_ops = &ffs_item_ops,
+ .ct_owner = THIS_MODULE,
+};
+
+
+/* Function registration interface ******************************************/
+
+static void ffs_free_inst(struct usb_function_instance *f)
+{
+ struct f_fs_opts *opts;
+
+ opts = to_f_fs_opts(f);
+ ffs_dev_lock();
+ ffs_free_dev(opts->dev);
+ ffs_dev_unlock();
+ kfree(opts);
+}
+
+#define MAX_INST_NAME_LEN 40
+
+static int ffs_set_inst_name(struct usb_function_instance *fi, const char *name)
+{
+ struct f_fs_opts *opts;
+ char *ptr;
+ const char *tmp;
+ int name_len, ret;
+
+ name_len = strlen(name) + 1;
+ if (name_len > MAX_INST_NAME_LEN)
+ return -ENAMETOOLONG;
+
+ ptr = kstrndup(name, name_len, GFP_KERNEL);
+ if (!ptr)
+ return -ENOMEM;
+
+ opts = to_f_fs_opts(fi);
+ tmp = NULL;
+
+ ffs_dev_lock();
+
+ tmp = opts->dev->name_allocated ? opts->dev->name : NULL;
+ ret = _ffs_name_dev(opts->dev, ptr);
+ if (ret) {
+ kfree(ptr);
+ ffs_dev_unlock();
+ return ret;
+ }
+ opts->dev->name_allocated = true;
+
+ ffs_dev_unlock();
+
+ kfree(tmp);
+
+ return 0;
+}
+
+static struct usb_function_instance *ffs_alloc_inst(void)
+{
+ struct f_fs_opts *opts;
+ struct ffs_dev *dev;
+
+ opts = kzalloc(sizeof(*opts), GFP_KERNEL);
+ if (!opts)
+ return ERR_PTR(-ENOMEM);
+
+ opts->func_inst.set_inst_name = ffs_set_inst_name;
+ opts->func_inst.free_func_inst = ffs_free_inst;
+ ffs_dev_lock();
+ dev = ffs_alloc_dev();
+ ffs_dev_unlock();
+ if (IS_ERR(dev)) {
+ kfree(opts);
+ return ERR_CAST(dev);
+ }
+ opts->dev = dev;
+ dev->opts = opts;
+
+ config_group_init_type_name(&opts->func_inst.group, "",
+ &ffs_func_type);
+ return &opts->func_inst;
+}
+
+static void ffs_free(struct usb_function *f)
+{
+ kfree(ffs_func_from_usb(f));
+}
+
+static void ffs_func_unbind(struct usb_configuration *c,
+ struct usb_function *f)
+{
+ struct ffs_function *func = ffs_func_from_usb(f);
+ struct ffs_data *ffs = func->ffs;
+ struct f_fs_opts *opts =
+ container_of(f->fi, struct f_fs_opts, func_inst);
+ struct ffs_ep *ep = func->eps;
+ unsigned count = ffs->eps_count;
+ unsigned long flags;
+
+ ENTER();
+ if (ffs->func == func) {
+ ffs_func_eps_disable(func);
+ ffs->func = NULL;
+ }
+
+ if (!--opts->refcnt)
+ functionfs_unbind(ffs);
+
+ /* cleanup after autoconfig */
+ spin_lock_irqsave(&func->ffs->eps_lock, flags);
+ do {
+ if (ep->ep && ep->req)
+ usb_ep_free_request(ep->ep, ep->req);
+ ep->req = NULL;
+ ++ep;
+ } while (--count);
+ spin_unlock_irqrestore(&func->ffs->eps_lock, flags);
+ kfree(func->eps);
+ func->eps = NULL;
+ /*
+ * eps, descriptors and interfaces_nums are allocated in the
+ * same chunk so only one free is required.
+ */
+ func->function.fs_descriptors = NULL;
+ func->function.hs_descriptors = NULL;
+ func->interfaces_nums = NULL;
+
+ ffs_event_add(ffs, FUNCTIONFS_UNBIND);
+}
+
+static struct usb_function *ffs_alloc(struct usb_function_instance *fi)
+{
+ struct ffs_function *func;
+
+ ENTER();
+
+ func = kzalloc(sizeof(*func), GFP_KERNEL);
+ if (unlikely(!func))
+ return ERR_PTR(-ENOMEM);
+
+ func->function.name = "Function FS Gadget";
+
+ func->function.bind = ffs_func_bind;
+ func->function.unbind = ffs_func_unbind;
+ func->function.set_alt = ffs_func_set_alt;
+ func->function.disable = ffs_func_disable;
+ func->function.setup = ffs_func_setup;
+ func->function.suspend = ffs_func_suspend;
+ func->function.resume = ffs_func_resume;
+ func->function.free_func = ffs_free;
+
+ return &func->function;
+}
+
+/*
+ * ffs_lock must be taken by the caller of this function
+ */
+struct ffs_dev *ffs_alloc_dev(void)
+{
+ struct ffs_dev *dev;
+ int ret;
+
+ if (ffs_get_single_dev())
+ return ERR_PTR(-EBUSY);
+
+ dev = kzalloc(sizeof(*dev), GFP_KERNEL);
+ if (!dev)
+ return ERR_PTR(-ENOMEM);
+
+ if (list_empty(&ffs_devices)) {
+ ret = functionfs_init();
+ if (ret) {
+ kfree(dev);
+ return ERR_PTR(ret);
+ }
+ }
+
+ list_add(&dev->entry, &ffs_devices);
+
+ return dev;
+}
+
+/*
+ * ffs_lock must be taken by the caller of this function
+ * The caller is responsible for "name" being available whenever f_fs needs it
+ */
+static int _ffs_name_dev(struct ffs_dev *dev, const char *name)
+{
+ struct ffs_dev *existing;
+
+ existing = _ffs_find_dev(name);
+ if (existing)
+ return -EBUSY;
+
+ dev->name = name;
+
+ return 0;
+}
+
+/*
+ * The caller is responsible for "name" being available whenever f_fs needs it
+ */
+int ffs_name_dev(struct ffs_dev *dev, const char *name)
+{
+ int ret;
+
+ ffs_dev_lock();
+ ret = _ffs_name_dev(dev, name);
+ ffs_dev_unlock();
+
+ return ret;
+}
+EXPORT_SYMBOL(ffs_name_dev);
+
+int ffs_single_dev(struct ffs_dev *dev)
+{
+ int ret;
+
+ ret = 0;
+ ffs_dev_lock();
+
+ if (!list_is_singular(&ffs_devices))
+ ret = -EBUSY;
+ else
+ dev->single = true;
+
+ ffs_dev_unlock();
+ return ret;
+}
+EXPORT_SYMBOL(ffs_single_dev);
+
+/*
+ * ffs_lock must be taken by the caller of this function
+ */
+void ffs_free_dev(struct ffs_dev *dev)
+{
+ list_del(&dev->entry);
+ if (dev->name_allocated)
+ kfree(dev->name);
+ kfree(dev);
+ if (list_empty(&ffs_devices))
+ functionfs_cleanup();
+}
+
+static void *ffs_acquire_dev(const char *dev_name)
+{
+ struct ffs_dev *ffs_dev;
+
+ ENTER();
+ ffs_dev_lock();
+
+ ffs_dev = ffs_find_dev(dev_name);
+ if (!ffs_dev)
+ ffs_dev = ERR_PTR(-ENODEV);
+ else if (ffs_dev->mounted)
+ ffs_dev = ERR_PTR(-EBUSY);
+ else if (ffs_dev->ffs_acquire_dev_callback &&
+ ffs_dev->ffs_acquire_dev_callback(ffs_dev))
+ ffs_dev = ERR_PTR(-ENODEV);
+ else
+ ffs_dev->mounted = true;
+
+ ffs_dev_unlock();
+ return ffs_dev;
+}
+
+static void ffs_release_dev(struct ffs_data *ffs_data)
+{
+ struct ffs_dev *ffs_dev;
+
+ ENTER();
+ ffs_dev_lock();
+
+ ffs_dev = ffs_data->private_data;
+ if (ffs_dev)
+ ffs_dev->mounted = false;
+
+ if (ffs_dev->ffs_release_dev_callback)
+ ffs_dev->ffs_release_dev_callback(ffs_dev);
+
+ ffs_dev_unlock();
+}
+
+static int ffs_ready(struct ffs_data *ffs)
+{
+ struct ffs_dev *ffs_obj;
+ int ret = 0;
+
+ ENTER();
+ ffs_dev_lock();
+
+ ffs_obj = ffs->private_data;
+ if (!ffs_obj) {
+ ret = -EINVAL;
+ goto done;
+ }
+ if (WARN_ON(ffs_obj->desc_ready)) {
+ ret = -EBUSY;
+ goto done;
+ }
+
+ ffs_obj->desc_ready = true;
+ ffs_obj->ffs_data = ffs;
+
+ if (ffs_obj->ffs_ready_callback)
+ ret = ffs_obj->ffs_ready_callback(ffs);
+
+done:
+ ffs_dev_unlock();
+ return ret;
+}
+
+static void ffs_closed(struct ffs_data *ffs)
+{
+ struct ffs_dev *ffs_obj;
+
+ ENTER();
+ ffs_dev_lock();
+
+ ffs_obj = ffs->private_data;
+ if (!ffs_obj)
+ goto done;
+
+ ffs_obj->desc_ready = false;
+
+ if (ffs_obj->ffs_closed_callback)
+ ffs_obj->ffs_closed_callback(ffs);
+
+ if (!ffs_obj->opts || ffs_obj->opts->no_configfs
+ || !ffs_obj->opts->func_inst.group.cg_item.ci_parent)
+ goto done;
+
+ unregister_gadget_item(ffs_obj->opts->
+ func_inst.group.cg_item.ci_parent->ci_parent);
+done:
+ ffs_dev_unlock();
+}
+
/* Misc helper functions ****************************************************/
static int ffs_mutex_lock(struct mutex *mutex, unsigned nonblock)
return data;
}
+
+DECLARE_USB_FUNCTION_INIT(ffs, ffs_alloc_inst, ffs_alloc);
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Michal Nazarewicz");
projects / cascardo / linux.git / blobdiff