kernel.git/drivers/uio/uio.c, branch linux-3.1.y

uio: fix allocating minor id for uio device

2011-04-19T23:56:03Z

The number of uio devices that could be used should be less than UIO_MAX_DEVICES by design, and this work guards any cases in which id more than UIO_MAX_DEVICES is utilized. Signed-off-by: Hillf Danton Signed-off-by: Hans J. Koch Signed-off-by: Greg Kroah-Hartman

uio: fix finding mm index for vma

2011-04-19T23:56:02Z

When finding mm index for vma it looks more flexible that the mm could be sparse, and both the size of mm and the pgoff of vma could give correct selection. Signed-off-by: Hillf Danton Signed-off-by: Hans J. Koch Signed-off-by: Greg Kroah-Hartman

uio: Change mail address of Hans J. Koch

2010-11-11T00:57:11Z

My old mail address doesn't exist anymore. This changes all occurrences to my new address. Signed-off-by: Hans J. Koch Signed-off-by: Greg Kroah-Hartman

Merge git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core-2.6

2010-10-23T02:36:42Z

* git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core-2.6: (31 commits) driver core: Display error codes when class suspend fails Driver core: Add section count to memory_block struct Driver core: Add mutex for adding/removing memory blocks Driver core: Move find_memory_block routine hpilo: Despecificate driver from iLO generation driver core: Convert link_mem_sections to use find_memory_block_hinted. driver core: Introduce find_memory_block_hinted which utilizes kset_find_obj_hinted. kobject: Introduce kset_find_obj_hinted. driver core: fix build for CONFIG_BLOCK not enabled driver-core: base: change to new flag variable sysfs: only access bin file vm_ops with the active lock sysfs: Fail bin file mmap if vma close is implemented. FW_LOADER: fix kconfig dependency warning on HOTPLUG uio: Statically allocate uio_class and use class .dev_attrs. uio: Support 2^MINOR_BITS minors uio: Cleanup irq handling. uio: Don't clear driver data uio: Fix lack of locking in init_uio_class SYSFS: Allow boot time switching between deprecated and modern sysfs layout driver core: remove CONFIG_SYSFS_DEPRECATED_V2 but keep it for block devices ...

uio: Statically allocate uio_class and use class .dev_attrs.

2010-10-22T17:16:43Z

Instead of adding uio class attributes manually after the uio device has been created and we have sent a uevent to userspace, use the class attribute mechanism. This removes races and makes the code simpler. At the same time don't bother to dynamically allocate a struct class for uio, just declare one statically. Less code is needed and it is easier to set the class parameters.tune the class Signed-off-by: Eric W. Biederman Reviewed-by: Thomas Gleixner Signed-off-by: Hans J. Koch Signed-off-by: Greg Kroah-Hartman

uio: Support 2^MINOR_BITS minors

2010-10-22T17:16:43Z

register_chrdev limits uio devices to 256 minor numbers which causes problems on one system I have with 384+ uio devices. So instead set UIO_MAX_DEVICES to the maximum number of minors and use alloc_chrdev_region to reserve the uio minors. The final result is that the code works the same but the uio driver now supports any minor the idr allocator comes up with. Signed-off-by: Eric W. Biederman Reviewed-by: Thomas Gleixner Signed-off-by: Hans J. Koch Signed-off-by: Greg Kroah-Hartman

uio: Cleanup irq handling.

2010-10-22T17:16:43Z

Change the value of UIO_IRQ_NONE -2 to 0. 0 is well defined in the rest of the kernel as the value to indicate an irq has not been assigned. Update the calls to request_irq and free_irq to only ignore UIO_IRQ_NONE and UIO_IRQ_CUSTOM allowing the rest of the kernel's possible irq numbers to be used. Signed-off-by: Eric W. Biederman Reviewed-by: Thomas Gleixner Signed-off-by: Hans J. Koch Signed-off-by: Greg Kroah-Hartman

uio: Don't clear driver data

2010-10-22T17:16:43Z

Currently uio sets it's driver data to NULL just as it is unregistering attributes. sysfs maks the guaranatee that it will not call attributes after device_destroy is called so this is unncessary and leads to lots of unnecessary code in uio.c Signed-off-by: Eric W. Biederman Reviewed-by: Thomas Gleixner Signed-off-by: Hans J. Koch Signed-off-by: Greg Kroah-Hartman

uio: Fix lack of locking in init_uio_class

2010-10-22T17:16:43Z

There is no locking in init_uio_class so multiple drivers can race and create multiple uio classes. Fix this by simplifying the code. In particular always register the uio class during module_init and make things simpler. Signed-off-by: Eric W. Biederman Reviewed-by: Thomas Gleixner Signed-off-by: Hans J. Koch Signed-off-by: Greg Kroah-Hartman

llseek: automatically add .llseek fop

2010-10-15T13:53:27Z

All file_operations should get a .llseek operation so we can make nonseekable_open the default for future file operations without a .llseek pointer. The three cases that we can automatically detect are no_llseek, seq_lseek and default_llseek. For cases where we can we can automatically prove that the file offset is always ignored, we use noop_llseek, which maintains the current behavior of not returning an error from a seek. New drivers should normally not use noop_llseek but instead use no_llseek and call nonseekable_open at open time. Existing drivers can be converted to do the same when the maintainer knows for certain that no user code relies on calling seek on the device file. The generated code is often incorrectly indented and right now contains comments that clarify for each added line why a specific variant was chosen. In the version that gets submitted upstream, the comments will be gone and I will manually fix the indentation, because there does not seem to be a way to do that using coccinelle. Some amount of new code is currently sitting in linux-next that should get the same modifications, which I will do at the end of the merge window. Many thanks to Julia Lawall for helping me learn to write a semantic patch that does all this. ===== begin semantic patch ===== // This adds an llseek= method to all file operations, // as a preparation for making no_llseek the default. // // The rules are // - use no_llseek explicitly if we do nonseekable_open // - use seq_lseek for sequential files // - use default_llseek if we know we access f_pos // - use noop_llseek if we know we don't access f_pos, // but we still want to allow users to call lseek // @ open1 exists @ identifier nested_open; @@ nested_open(...) { <+... nonseekable_open(...) ...+> } @ open exists@ identifier open_f; identifier i, f; identifier open1.nested_open; @@ int open_f(struct inode *i, struct file *f) { <+... ( nonseekable_open(...) | nested_open(...) ) ...+> } @ read disable optional_qualifier exists @ identifier read_f; identifier f, p, s, off; type ssize_t, size_t, loff_t; expression E; identifier func; @@ ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off) { <+... ( *off = E | *off += E | func(..., off, ...) | E = *off ) ...+> } @ read_no_fpos disable optional_qualifier exists @ identifier read_f; identifier f, p, s, off; type ssize_t, size_t, loff_t; @@ ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off) { ... when != off } @ write @ identifier write_f; identifier f, p, s, off; type ssize_t, size_t, loff_t; expression E; identifier func; @@ ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off) { <+... ( *off = E | *off += E | func(..., off, ...) | E = *off ) ...+> } @ write_no_fpos @ identifier write_f; identifier f, p, s, off; type ssize_t, size_t, loff_t; @@ ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off) { ... when != off } @ fops0 @ identifier fops; @@ struct file_operations fops = { ... }; @ has_llseek depends on fops0 @ identifier fops0.fops; identifier llseek_f; @@ struct file_operations fops = { ... .llseek = llseek_f, ... }; @ has_read depends on fops0 @ identifier fops0.fops; identifier read_f; @@ struct file_operations fops = { ... .read = read_f, ... }; @ has_write depends on fops0 @ identifier fops0.fops; identifier write_f; @@ struct file_operations fops = { ... .write = write_f, ... }; @ has_open depends on fops0 @ identifier fops0.fops; identifier open_f; @@ struct file_operations fops = { ... .open = open_f, ... }; // use no_llseek if we call nonseekable_open //////////////////////////////////////////// @ nonseekable1 depends on !has_llseek && has_open @ identifier fops0.fops; identifier nso ~= "nonseekable_open"; @@ struct file_operations fops = { ... .open = nso, ... +.llseek = no_llseek, /* nonseekable */ }; @ nonseekable2 depends on !has_llseek @ identifier fops0.fops; identifier open.open_f; @@ struct file_operations fops = { ... .open = open_f, ... +.llseek = no_llseek, /* open uses nonseekable */ }; // use seq_lseek for sequential files ///////////////////////////////////// @ seq depends on !has_llseek @ identifier fops0.fops; identifier sr ~= "seq_read"; @@ struct file_operations fops = { ... .read = sr, ... +.llseek = seq_lseek, /* we have seq_read */ }; // use default_llseek if there is a readdir /////////////////////////////////////////// @ fops1 depends on !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier readdir_e; @@ // any other fop is used that changes pos struct file_operations fops = { ... .readdir = readdir_e, ... +.llseek = default_llseek, /* readdir is present */ }; // use default_llseek if at least one of read/write touches f_pos ///////////////////////////////////////////////////////////////// @ fops2 depends on !fops1 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier read.read_f; @@ // read fops use offset struct file_operations fops = { ... .read = read_f, ... +.llseek = default_llseek, /* read accesses f_pos */ }; @ fops3 depends on !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier write.write_f; @@ // write fops use offset struct file_operations fops = { ... .write = write_f, ... + .llseek = default_llseek, /* write accesses f_pos */ }; // Use noop_llseek if neither read nor write accesses f_pos /////////////////////////////////////////////////////////// @ fops4 depends on !fops1 && !fops2 && !fops3 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier read_no_fpos.read_f; identifier write_no_fpos.write_f; @@ // write fops use offset struct file_operations fops = { ... .write = write_f, .read = read_f, ... +.llseek = noop_llseek, /* read and write both use no f_pos */ }; @ depends on has_write && !has_read && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier write_no_fpos.write_f; @@ struct file_operations fops = { ... .write = write_f, ... +.llseek = noop_llseek, /* write uses no f_pos */ }; @ depends on has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier read_no_fpos.read_f; @@ struct file_operations fops = { ... .read = read_f, ... +.llseek = noop_llseek, /* read uses no f_pos */ }; @ depends on !has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; @@ struct file_operations fops = { ... +.llseek = noop_llseek, /* no read or write fn */ }; ===== End semantic patch ===== Signed-off-by: Arnd Bergmann Cc: Julia Lawall Cc: Christoph Hellwig