#include #include #include /* does _NOT_ require i_mutex to be held. * * This function cannot be inlined since i_size_{read,write} is rather * heavy-weight on 32-bit systems */ void fsstack_copy_inode_size(struct inode *dst, struct inode *src) { loff_t i_size; blkcnt_t i_blocks; /* * i_size_read() includes its own seqlocking and protection from * preemption (see include/linux/fs.h): we need nothing extra for * that here, and prefer to avoid nesting locks than attempt to keep * i_size and i_blocks in sync together. */ i_size = i_size_read(src); /* * But if CONFIG_LBDAF (on 32-bit), we ought to make an effort to * keep the two halves of i_blocks in sync despite SMP or PREEMPT - * though stat's generic_fillattr() doesn't bother, and we won't be * applying quotas (where i_blocks does become important) at the * upper level. * * We don't actually know what locking is used at the lower level; * but if it's a filesystem that supports quotas, it will be using * i_lock as in inode_add_bytes(). */ if (sizeof(i_blocks) > sizeof(long)) spin_lock(&src->i_lock); i_blocks = src->i_blocks; if (sizeof(i_blocks) > sizeof(long)) spin_unlock(&src->i_lock); /* * If CONFIG_SMP or CONFIG_PREEMPT on 32-bit, it's vital for * fsstack_copy_inode_size() to hold some lock around * i_size_write(), otherwise i_size_read() may spin forever (see * include/linux/fs.h). We don't necessarily hold i_mutex when this * is called, so take i_lock for that case. * * And if CONFIG_LBDAF (on 32-bit), continue our effort to keep the * two halves of i_blocks in sync despite SMP or PREEMPT: use i_lock * for that case too, and do both at once by combining the tests. * * There is none of this locking overhead in the 64-bit case. */ if (sizeof(i_size) > sizeof(long) || sizeof(i_blocks) > sizeof(long)) spin_lock(&dst->i_lock); i_size_write(dst, i_size); dst->i_blocks = i_blocks; if (sizeof(i_size) > sizeof(long) || sizeof(i_blocks) > sizeof(long)) spin_unlock(&dst->i_lock); } EXPORT_SYMBOL_GPL(fsstack_copy_inode_size); /* copy all attributes */ void fsstack_copy_attr_all(struct inode *dest, const struct inode *src) { dest->i_mode = src->i_mode; dest->i_uid = src->i_uid; dest->i_gid = src->i_gid; dest->i_rdev = src->i_rdev; dest->i_atime = src->i_atime; dest->i_mtime = src->i_mtime; dest->i_ctime = src->i_ctime; dest->i_blkbits = src->i_blkbits; dest->i_flags = src->i_flags; set_nlink(dest, src->i_nlink); } EXPORT_SYMBOL_GPL(fsstack_copy_attr_all); ='q' value=''/>
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authorThomas Gleixner <tglx@linutronix.de>2017-01-31 09:37:34 +0100
committerThomas Gleixner <tglx@linutronix.de>2017-01-31 21:47:58 +0100
commit0becc0ae5b42828785b589f686725ff5bc3b9b25 (patch)
treebe6d0e1f37c38ed0a7dd5da2d4b1e93f0fb43101 /include/net/caif/cfsrvl.h
parent24c2503255d35c269b67162c397a1a1c1e02f6ce (diff)
x86/mce: Make timer handling more robust
Erik reported that on a preproduction hardware a CMCI storm triggers the BUG_ON in add_timer_on(). The reason is that the per CPU MCE timer is started by the CMCI logic before the MCE CPU hotplug callback starts the timer with add_timer_on(). So the timer is already queued which triggers the BUG. Using add_timer_on() is pretty pointless in this code because the timer is strictlty per CPU, initialized as pinned and all operations which arm the timer happen on the CPU to which the timer belongs. Simplify the whole machinery by using mod_timer() instead of add_timer_on() which avoids the problem because mod_timer() can handle already queued timers. Use __start_timer() everywhere so the earliest armed expiry time is preserved. Reported-by: Erik Veijola <erik.veijola@intel.com> Tested-by: Borislav Petkov <bp@alien8.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Borislav Petkov <bp@alien8.de> Cc: Tony Luck <tony.luck@intel.com> Link: http://lkml.kernel.org/r/alpine.DEB.2.20.1701310936080.3457@nanos Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Diffstat (limited to 'include/net/caif/cfsrvl.h')