From b4caecd48005fbed3949dde6c1cb233142fd69e9 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Wed, 14 Jan 2015 10:42:32 +0100 Subject: fs: introduce f_op->mmap_capabilities for nommu mmap support Since "BDI: Provide backing device capability information [try #3]" the backing_dev_info structure also provides flags for the kind of mmap operation available in a nommu environment, which is entirely unrelated to it's original purpose. Introduce a new nommu-only file operation to provide this information to the nommu mmap code instead. Splitting this from the backing_dev_info structure allows to remove lots of backing_dev_info instance that aren't otherwise needed, and entirely gets rid of the concept of providing a backing_dev_info for a character device. It also removes the need for the mtd_inodefs filesystem. Signed-off-by: Christoph Hellwig Reviewed-by: Tejun Heo Acked-by: Brian Norris Signed-off-by: Jens Axboe --- drivers/mtd/mtdchar.c | 72 +++++++------------------------------------- drivers/mtd/mtdconcat.c | 10 ------- drivers/mtd/mtdcore.c | 80 ++++++++++++++----------------------------------- drivers/mtd/mtdpart.c | 1 - 4 files changed, 32 insertions(+), 131 deletions(-) (limited to 'drivers/mtd') diff --git a/drivers/mtd/mtdchar.c b/drivers/mtd/mtdchar.c index 53563955931b..55fa27ecf4e1 100644 --- a/drivers/mtd/mtdchar.c +++ b/drivers/mtd/mtdchar.c @@ -49,7 +49,6 @@ static DEFINE_MUTEX(mtd_mutex); */ struct mtd_file_info { struct mtd_info *mtd; - struct inode *ino; enum mtd_file_modes mode; }; @@ -59,10 +58,6 @@ static loff_t mtdchar_lseek(struct file *file, loff_t offset, int orig) return fixed_size_llseek(file, offset, orig, mfi->mtd->size); } -static int count; -static struct vfsmount *mnt; -static struct file_system_type mtd_inodefs_type; - static int mtdchar_open(struct inode *inode, struct file *file) { int minor = iminor(inode); @@ -70,7 +65,6 @@ static int mtdchar_open(struct inode *inode, struct file *file) int ret = 0; struct mtd_info *mtd; struct mtd_file_info *mfi; - struct inode *mtd_ino; pr_debug("MTD_open\n"); @@ -78,10 +72,6 @@ static int mtdchar_open(struct inode *inode, struct file *file) if ((file->f_mode & FMODE_WRITE) && (minor & 1)) return -EACCES; - ret = simple_pin_fs(&mtd_inodefs_type, &mnt, &count); - if (ret) - return ret; - mutex_lock(&mtd_mutex); mtd = get_mtd_device(NULL, devnum); @@ -95,43 +85,26 @@ static int mtdchar_open(struct inode *inode, struct file *file) goto out1; } - mtd_ino = iget_locked(mnt->mnt_sb, devnum); - if (!mtd_ino) { - ret = -ENOMEM; - goto out1; - } - if (mtd_ino->i_state & I_NEW) { - mtd_ino->i_private = mtd; - mtd_ino->i_mode = S_IFCHR; - mtd_ino->i_data.backing_dev_info = mtd->backing_dev_info; - unlock_new_inode(mtd_ino); - } - file->f_mapping = mtd_ino->i_mapping; - /* You can't open it RW if it's not a writeable device */ if ((file->f_mode & FMODE_WRITE) && !(mtd->flags & MTD_WRITEABLE)) { ret = -EACCES; - goto out2; + goto out1; } mfi = kzalloc(sizeof(*mfi), GFP_KERNEL); if (!mfi) { ret = -ENOMEM; - goto out2; + goto out1; } - mfi->ino = mtd_ino; mfi->mtd = mtd; file->private_data = mfi; mutex_unlock(&mtd_mutex); return 0; -out2: - iput(mtd_ino); out1: put_mtd_device(mtd); out: mutex_unlock(&mtd_mutex); - simple_release_fs(&mnt, &count); return ret; } /* mtdchar_open */ @@ -148,12 +121,9 @@ static int mtdchar_close(struct inode *inode, struct file *file) if ((file->f_mode & FMODE_WRITE)) mtd_sync(mtd); - iput(mfi->ino); - put_mtd_device(mtd); file->private_data = NULL; kfree(mfi); - simple_release_fs(&mnt, &count); return 0; } /* mtdchar_close */ @@ -1117,6 +1087,13 @@ static unsigned long mtdchar_get_unmapped_area(struct file *file, ret = mtd_get_unmapped_area(mtd, len, offset, flags); return ret == -EOPNOTSUPP ? -ENODEV : ret; } + +static unsigned mtdchar_mmap_capabilities(struct file *file) +{ + struct mtd_file_info *mfi = file->private_data; + + return mtd_mmap_capabilities(mfi->mtd); +} #endif /* @@ -1160,27 +1137,10 @@ static const struct file_operations mtd_fops = { .mmap = mtdchar_mmap, #ifndef CONFIG_MMU .get_unmapped_area = mtdchar_get_unmapped_area, + .mmap_capabilities = mtdchar_mmap_capabilities, #endif }; -static const struct super_operations mtd_ops = { - .drop_inode = generic_delete_inode, - .statfs = simple_statfs, -}; - -static struct dentry *mtd_inodefs_mount(struct file_system_type *fs_type, - int flags, const char *dev_name, void *data) -{ - return mount_pseudo(fs_type, "mtd_inode:", &mtd_ops, NULL, MTD_INODE_FS_MAGIC); -} - -static struct file_system_type mtd_inodefs_type = { - .name = "mtd_inodefs", - .mount = mtd_inodefs_mount, - .kill_sb = kill_anon_super, -}; -MODULE_ALIAS_FS("mtd_inodefs"); - int __init init_mtdchar(void) { int ret; @@ -1193,23 +1153,11 @@ int __init init_mtdchar(void) return ret; } - ret = register_filesystem(&mtd_inodefs_type); - if (ret) { - pr_err("Can't register mtd_inodefs filesystem, error %d\n", - ret); - goto err_unregister_chdev; - } - - return ret; - -err_unregister_chdev: - __unregister_chrdev(MTD_CHAR_MAJOR, 0, 1 << MINORBITS, "mtd"); return ret; } void __exit cleanup_mtdchar(void) { - unregister_filesystem(&mtd_inodefs_type); __unregister_chrdev(MTD_CHAR_MAJOR, 0, 1 << MINORBITS, "mtd"); } diff --git a/drivers/mtd/mtdconcat.c b/drivers/mtd/mtdconcat.c index b9000563b9f4..eacc3aac7327 100644 --- a/drivers/mtd/mtdconcat.c +++ b/drivers/mtd/mtdconcat.c @@ -732,8 +732,6 @@ struct mtd_info *mtd_concat_create(struct mtd_info *subdev[], /* subdevices to c concat->mtd.ecc_stats.badblocks = subdev[0]->ecc_stats.badblocks; - concat->mtd.backing_dev_info = subdev[0]->backing_dev_info; - concat->subdev[0] = subdev[0]; for (i = 1; i < num_devs; i++) { @@ -761,14 +759,6 @@ struct mtd_info *mtd_concat_create(struct mtd_info *subdev[], /* subdevices to c subdev[i]->flags & MTD_WRITEABLE; } - /* only permit direct mapping if the BDIs are all the same - * - copy-mapping is still permitted - */ - if (concat->mtd.backing_dev_info != - subdev[i]->backing_dev_info) - concat->mtd.backing_dev_info = - &default_backing_dev_info; - concat->mtd.size += subdev[i]->size; concat->mtd.ecc_stats.badblocks += subdev[i]->ecc_stats.badblocks; diff --git a/drivers/mtd/mtdcore.c b/drivers/mtd/mtdcore.c index 4c611871d7e6..ff38a1df22f7 100644 --- a/drivers/mtd/mtdcore.c +++ b/drivers/mtd/mtdcore.c @@ -43,33 +43,7 @@ #include "mtdcore.h" -/* - * backing device capabilities for non-mappable devices (such as NAND flash) - * - permits private mappings, copies are taken of the data - */ -static struct backing_dev_info mtd_bdi_unmappable = { - .capabilities = BDI_CAP_MAP_COPY, -}; - -/* - * backing device capabilities for R/O mappable devices (such as ROM) - * - permits private mappings, copies are taken of the data - * - permits non-writable shared mappings - */ -static struct backing_dev_info mtd_bdi_ro_mappable = { - .capabilities = (BDI_CAP_MAP_COPY | BDI_CAP_MAP_DIRECT | - BDI_CAP_EXEC_MAP | BDI_CAP_READ_MAP), -}; - -/* - * backing device capabilities for writable mappable devices (such as RAM) - * - permits private mappings, copies are taken of the data - * - permits non-writable shared mappings - */ -static struct backing_dev_info mtd_bdi_rw_mappable = { - .capabilities = (BDI_CAP_MAP_COPY | BDI_CAP_MAP_DIRECT | - BDI_CAP_EXEC_MAP | BDI_CAP_READ_MAP | - BDI_CAP_WRITE_MAP), +static struct backing_dev_info mtd_bdi = { }; static int mtd_cls_suspend(struct device *dev, pm_message_t state); @@ -365,6 +339,22 @@ static struct device_type mtd_devtype = { .release = mtd_release, }; +#ifndef CONFIG_MMU +unsigned mtd_mmap_capabilities(struct mtd_info *mtd) +{ + switch (mtd->type) { + case MTD_RAM: + return NOMMU_MAP_COPY | NOMMU_MAP_DIRECT | NOMMU_MAP_EXEC | + NOMMU_MAP_READ | NOMMU_MAP_WRITE; + case MTD_ROM: + return NOMMU_MAP_COPY | NOMMU_MAP_DIRECT | NOMMU_MAP_EXEC | + NOMMU_MAP_READ; + default: + return NOMMU_MAP_COPY; + } +} +#endif + /** * add_mtd_device - register an MTD device * @mtd: pointer to new MTD device info structure @@ -380,19 +370,7 @@ int add_mtd_device(struct mtd_info *mtd) struct mtd_notifier *not; int i, error; - if (!mtd->backing_dev_info) { - switch (mtd->type) { - case MTD_RAM: - mtd->backing_dev_info = &mtd_bdi_rw_mappable; - break; - case MTD_ROM: - mtd->backing_dev_info = &mtd_bdi_ro_mappable; - break; - default: - mtd->backing_dev_info = &mtd_bdi_unmappable; - break; - } - } + mtd->backing_dev_info = &mtd_bdi; BUG_ON(mtd->writesize == 0); mutex_lock(&mtd_table_mutex); @@ -1237,17 +1215,9 @@ static int __init init_mtd(void) if (ret) goto err_reg; - ret = mtd_bdi_init(&mtd_bdi_unmappable, "mtd-unmap"); - if (ret) - goto err_bdi1; - - ret = mtd_bdi_init(&mtd_bdi_ro_mappable, "mtd-romap"); - if (ret) - goto err_bdi2; - - ret = mtd_bdi_init(&mtd_bdi_rw_mappable, "mtd-rwmap"); + ret = mtd_bdi_init(&mtd_bdi, "mtd"); if (ret) - goto err_bdi3; + goto err_bdi; proc_mtd = proc_create("mtd", 0, NULL, &mtd_proc_ops); @@ -1260,11 +1230,7 @@ static int __init init_mtd(void) out_procfs: if (proc_mtd) remove_proc_entry("mtd", NULL); -err_bdi3: - bdi_destroy(&mtd_bdi_ro_mappable); -err_bdi2: - bdi_destroy(&mtd_bdi_unmappable); -err_bdi1: +err_bdi: class_unregister(&mtd_class); err_reg: pr_err("Error registering mtd class or bdi: %d\n", ret); @@ -1277,9 +1243,7 @@ static void __exit cleanup_mtd(void) if (proc_mtd) remove_proc_entry("mtd", NULL); class_unregister(&mtd_class); - bdi_destroy(&mtd_bdi_unmappable); - bdi_destroy(&mtd_bdi_ro_mappable); - bdi_destroy(&mtd_bdi_rw_mappable); + bdi_destroy(&mtd_bdi); } module_init(init_mtd); diff --git a/drivers/mtd/mtdpart.c b/drivers/mtd/mtdpart.c index a3e3a7d074d5..e779de315ade 100644 --- a/drivers/mtd/mtdpart.c +++ b/drivers/mtd/mtdpart.c @@ -378,7 +378,6 @@ static struct mtd_part *allocate_partition(struct mtd_info *master, slave->mtd.name = name; slave->mtd.owner = master->owner; - slave->mtd.backing_dev_info = master->backing_dev_info; /* NOTE: we don't arrange MTDs as a tree; it'd be error-prone * to have the same data be in two different partitions. -- cgit v1.2.3