user/sven/linux.git/lib/dma-debug.c, branch v3.4.48

Remove useless get_driver()/put_driver() calls

2012-01-25T00:00:35Z

As part of the removal of get_driver()/put_driver(), this patch (as1512) gets rid of various useless and unnecessary calls in several drivers. In some cases it may be desirable to pin the driver by calling try_module_get(), but that can be done later. Signed-off-by: Alan Stern CC: "David S. Miller" CC: Konrad Rzeszutek Wilk CC: Michael Buesch CC: Joerg Roedel Signed-off-by: Greg Kroah-Hartman

Fix comparison using wrong pointer variable in dma debug code

2011-11-21T10:35:37Z

cppcheck reported: [lib/dma-debug.c:248] -> [lib/dma-debug.c:248]: (style) Same expression on both sides of '=='. Signed-off-by: Thomas Jarosch Signed-off-by: Joerg Roedel

lib: dma-debug needs export.h for EXPORT_SYMBOL

2011-10-31T23:32:23Z

There are no modular calls here, so just the minimal header for the EXPORT_SYMBOL macro will suffice. Signed-off-by: Paul Gortmaker

dma-debug: hash_bucket_find needs to allow for offsets within an entry

2011-08-23T13:36:00Z

Summary: Users of the pci_dma_sync_single_* api allow users to sync address ranges within the range of a mapped entry (i.e. you can dma map address X to dma_addr_t A and then pci_dma_sync_single on dma_addr_t A+1. The dma-debug library however assume dma syncs will always occur using the base address of a mapped region, and uses that assumption to find entries in its hash table. Since thats often (but not always the case), the dma debug library can give us false errors about missing entries, which are reported as syncing of memory not allocated by the driver. This was noted in the cxgb3 driver as this error: WARNING: at lib/dma-debug.c:902 check_sync+0xdd/0x48c() Hardware name: To be filled by O.E.M. cxgb3 0000:01:00.0: DMA-API: device driver tries to sync DMA memory it has not allocated [device address=0x00000000fff97800] [size=1984 bytes] Modules linked in: autofs4 sunrpc cpufreq_ondemand acpi_cpufreq freq_table mperf ip6t_REJECT nf_conntrack_ipv6 ip6table_filter ip6_tables ipv6 uinput snd_hda_codec_intelhdmi snd_hda_codec_realtek snd_hda_intel snd_hda_codec snd_hwdep snd_seq snd_seq_device snd_pcm snd_timer e1000e snd soundcore r8169 cxgb3 iTCO_wdt snd_page_alloc mii shpchp i2c_i801 iTCO_vendor_support mdio microcode firewire_ohci firewire_core crc_itu_t ata_generic pata_acpi i915 drm_kms_helper drm i2c_algo_bit i2c_core video output [last unloaded: scsi_wait_scan] Pid: 1818, comm: ifconfig Not tainted 2.6.35-0.23.rc3.git6.fc14.x86_64 #1 Call Trace: [] warn_slowpath_common+0x85/0x9d [] warn_slowpath_fmt+0x46/0x48 [] ? check_sync+0x39/0x48c [] ? trace_hardirqs_on+0xd/0xf [] check_sync+0xdd/0x48c [] debug_dma_sync_single_for_device+0x3f/0x41 [] ? pci_map_page+0x84/0x97 [cxgb3] [] pci_dma_sync_single_for_device.clone.0+0x65/0x6e [cxgb3] [] refill_fl+0x305/0x30a [cxgb3] [] t3_sge_alloc_qset+0x6a7/0x821 [cxgb3] [] cxgb_up+0x4d0/0xe62 [cxgb3] [] ? __module_text_address+0x12/0x58 [] cxgb_open+0x3f/0x309 [cxgb3] [] __dev_open+0x8e/0xbc [] __dev_change_flags+0xbe/0x142 [] dev_change_flags+0x21/0x57 [] devinet_ioctl+0x29a/0x54b [] ? inode_has_perm+0xaa/0xce [] inet_ioctl+0x8f/0xa7 [] sock_do_ioctl+0x29/0x48 [] sock_ioctl+0x213/0x222 [] vfs_ioctl+0x32/0xa6 [] do_vfs_ioctl+0x47a/0x4b3 [] sys_ioctl+0x56/0x79 [] system_call_fastpath+0x16/0x1b ---[ end trace 69a4d4cc77b58004 ]--- (some edits by Joerg Roedel) Signed-off-by: Neil Horman Reported-by: Jay Fenalson CC: Divy LeRay CC: Stanislaw Gruszka CC: Joerg Roedel CC: Arnd Bergmann Signed-off-by: Joerg Roedel

dma-debug: print information about leaked entry

2011-04-07T14:31:19Z

When driver leak dma mapping, print additional information about one of leaked entries, to to help investigate problem. Patch should be useful for debugging drivers, which maps many different class of buffers. Signed-off-by: Stanislaw Gruszka Signed-off-by: Joerg Roedel

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

dma-debug: Cleanup for copy-loop in filter_write()

2010-04-07T12:36:27Z

Earlier in this function we set the last byte of "buf" to NULL so we always hit the break statement and "i" is never equal to NAME_MAX_LEN. This patch doesn't change how the driver works but it silences a Smatch warning and it makes it clearer that we don't write past the end of the array. Signed-off-by: Dan Carpenter Signed-off-by: Joerg Roedel

Merge branches 'amd-iommu/fixes' and 'dma-debug/fixes' into iommu/fixes

2010-01-22T17:00:41Z

lib/dma-debug.c: mark file-local struct symbol static.

2010-01-22T16:59:51Z

warning: symbol 'filter_fops' was not declared. Should it be static? Signed-off-by: Thiago Farina Signed-off-by: Joerg Roedel

dma-debug: allow DMA_BIDIRECTIONAL mappings to be synced with DMA_FROM_DEVICE and

2010-01-11T17:34:04Z

There is no need to perform full BIDIR sync (copying the buffers in case of swiotlb and similar schemes) if we know that the owner (CPU or device) hasn't altered the data. Addresses the false-positive reported at http://bugzilla.kernel.org/show_bug.cgi?id=14169 Signed-off-by: Krzysztof Halasa Cc: David Miller Cc: Joerg Roedel Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds