diff options
Diffstat (limited to 'drivers/usb/gadget/f_fs.c')
| -rw-r--r-- | drivers/usb/gadget/f_fs.c | 1014 |
1 files changed, 622 insertions, 392 deletions
diff --git a/drivers/usb/gadget/f_fs.c b/drivers/usb/gadget/f_fs.c index 774e8b89cdb5..306a2b52125c 100644 --- a/drivers/usb/gadget/f_fs.c +++ b/drivers/usb/gadget/f_fs.c @@ -22,218 +22,42 @@ #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); @@ -274,15 +98,12 @@ static struct ffs_function *ffs_func_from_usb(struct usb_function *f) 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 *, @@ -335,6 +156,17 @@ ffs_sb_create_file(struct super_block *sb, const char *name, void *data, 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 ****************************************************/ @@ -460,7 +292,7 @@ static ssize_t ffs_ep0_write(struct file *file, const char __user *buf, 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; @@ -753,78 +585,71 @@ static ssize_t ffs_epfile_io(struct file *file, 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; - /* We will be using request */ - ret = ffs_mutex_lock(&epfile->mutex, - file->f_flags & O_NONBLOCK); - if (unlikely(ret)) + data = kmalloc(data_len, GFP_KERNEL); + if (unlikely(!data)) + return -ENOMEM; + + 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); @@ -837,7 +662,7 @@ first_try: 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); @@ -849,9 +674,17 @@ first_try: 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; } } @@ -1191,7 +1024,7 @@ ffs_fs_mount(struct file_system_type *t, int flags, 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); @@ -1201,7 +1034,7 @@ ffs_fs_mount(struct file_system_type *t, int flags, 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; @@ -1214,7 +1047,7 @@ ffs_fs_kill_sb(struct super_block *sb) 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); } } @@ -1304,7 +1137,7 @@ static struct ffs_data *ffs_data_new(void) { struct ffs_data *ffs = kzalloc(sizeof *ffs, GFP_KERNEL); if (unlikely(!ffs)) - return 0; + return NULL; ENTER(); @@ -1327,7 +1160,7 @@ static void ffs_data_clear(struct ffs_data *ffs) ENTER(); if (test_and_clear_bit(FFS_FL_CALL_CLOSED_CALLBACK, &ffs->flags)) - functionfs_closed_callback(ffs); + ffs_closed(ffs); BUG_ON(ffs->gadget); @@ -1463,71 +1296,6 @@ static void ffs_epfiles_destroy(struct ffs_epfile *epfiles, unsigned count) 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) { @@ -1901,30 +1669,34 @@ static int __ffs_data_got_strings(struct ffs_data *ffs, /* 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)); - d = kmalloc(sizeof *d, GFP_KERNEL); - if (unlikely(!d)) { + char *vlabuf = kmalloc(vla_group_size(d), GFP_KERNEL); + + 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; } @@ -2187,8 +1959,57 @@ static int __ffs_func_bind_do_nums(enum ffs_entity_type type, u8 *valuep, 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; @@ -2200,16 +2021,16 @@ static int ffs_func_bind(struct usb_configuration *c, 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(); @@ -2217,21 +2038,28 @@ static int ffs_func_bind(struct usb_configuration *c, 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 @@ -2239,10 +2067,10 @@ static int ffs_func_bind(struct usb_configuration *c, * 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; @@ -2251,10 +2079,10 @@ static int ffs_func_bind(struct usb_configuration *c, } 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; @@ -2267,7 +2095,7 @@ static int ffs_func_bind(struct usb_configuration *c, */ 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; @@ -2281,26 +2109,19 @@ 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) @@ -2428,6 +2249,411 @@ static int ffs_func_revmap_intf(struct ffs_function *func, u8 intf) } +/* 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) @@ -2458,3 +2684,7 @@ static char *ffs_prepare_buffer(const char __user *buf, size_t len) return data; } + +DECLARE_USB_FUNCTION_INIT(ffs, ffs_alloc_inst, ffs_alloc); +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Michal Nazarewicz"); |