From 3f3aaea29ff7ee2d43b430338427f30ba7f60ff9 Mon Sep 17 00:00:00 2001 From: Konrad Rzeszutek Wilk Date: Fri, 30 Mar 2012 11:45:01 -0400 Subject: xen/p2m: Move code around to allow for better re-usage. We are going to be using the early_alloc_p2m (and early_alloc_p2m_middle) code in follow up patches which are not related to setting identity pages. Hence lets move the code out in its own function and rename them as appropiate. Signed-off-by: Konrad Rzeszutek Wilk --- arch/x86/xen/p2m.c | 62 ++++++++++++++++++++++++++++++------------------------ 1 file changed, 34 insertions(+), 28 deletions(-) diff --git a/arch/x86/xen/p2m.c b/arch/x86/xen/p2m.c index 1b267e75158d..3cc3afeb09a1 100644 --- a/arch/x86/xen/p2m.c +++ b/arch/x86/xen/p2m.c @@ -499,7 +499,7 @@ static bool alloc_p2m(unsigned long pfn) return true; } -static bool __init __early_alloc_p2m(unsigned long pfn) +static bool __init early_alloc_p2m_middle(unsigned long pfn) { unsigned topidx, mididx, idx; @@ -541,6 +541,36 @@ static bool __init __early_alloc_p2m(unsigned long pfn) } return idx != 0; } + +static bool __init early_alloc_p2m(unsigned long pfn) +{ + unsigned topidx = p2m_top_index(pfn); + unsigned long *mid_mfn_p; + unsigned long **mid; + + mid = p2m_top[topidx]; + mid_mfn_p = p2m_top_mfn_p[topidx]; + if (mid == p2m_mid_missing) { + mid = extend_brk(PAGE_SIZE, PAGE_SIZE); + + p2m_mid_init(mid); + + p2m_top[topidx] = mid; + + BUG_ON(mid_mfn_p != p2m_mid_missing_mfn); + } + /* And the save/restore P2M tables.. */ + if (mid_mfn_p == p2m_mid_missing_mfn) { + mid_mfn_p = extend_brk(PAGE_SIZE, PAGE_SIZE); + p2m_mid_mfn_init(mid_mfn_p); + + p2m_top_mfn_p[topidx] = mid_mfn_p; + p2m_top_mfn[topidx] = virt_to_mfn(mid_mfn_p); + /* Note: we don't set mid_mfn_p[midix] here, + * look in early_alloc_p2m_middle */ + } + return true; +} unsigned long __init set_phys_range_identity(unsigned long pfn_s, unsigned long pfn_e) { @@ -559,35 +589,11 @@ unsigned long __init set_phys_range_identity(unsigned long pfn_s, pfn < ALIGN(pfn_e, (P2M_MID_PER_PAGE * P2M_PER_PAGE)); pfn += P2M_MID_PER_PAGE * P2M_PER_PAGE) { - unsigned topidx = p2m_top_index(pfn); - unsigned long *mid_mfn_p; - unsigned long **mid; - - mid = p2m_top[topidx]; - mid_mfn_p = p2m_top_mfn_p[topidx]; - if (mid == p2m_mid_missing) { - mid = extend_brk(PAGE_SIZE, PAGE_SIZE); - - p2m_mid_init(mid); - - p2m_top[topidx] = mid; - - BUG_ON(mid_mfn_p != p2m_mid_missing_mfn); - } - /* And the save/restore P2M tables.. */ - if (mid_mfn_p == p2m_mid_missing_mfn) { - mid_mfn_p = extend_brk(PAGE_SIZE, PAGE_SIZE); - p2m_mid_mfn_init(mid_mfn_p); - - p2m_top_mfn_p[topidx] = mid_mfn_p; - p2m_top_mfn[topidx] = virt_to_mfn(mid_mfn_p); - /* Note: we don't set mid_mfn_p[midix] here, - * look in __early_alloc_p2m */ - } + WARN_ON(!early_alloc_p2m(pfn)); } - __early_alloc_p2m(pfn_s); - __early_alloc_p2m(pfn_e); + early_alloc_p2m_middle(pfn_s); + early_alloc_p2m_middle(pfn_e); for (pfn = pfn_s; pfn < pfn_e; pfn++) if (!__set_phys_to_machine(pfn, IDENTITY_FRAME(pfn))) -- cgit v1.2.3 From cef4cca551d652b7f69c9d76337c5fae24e069dc Mon Sep 17 00:00:00 2001 From: Konrad Rzeszutek Wilk Date: Fri, 30 Mar 2012 14:15:14 -0400 Subject: xen/p2m: Allow alloc_p2m_middle to call reserve_brk depending on argument For identity cases we want to call reserve_brk only on the boundary conditions of the middle P2M (so P2M[x][y][0] = extend_brk). This is to work around identify regions (PCI spaces, gaps in E820) which are not aligned on 2MB regions. However for the case were we want to allocate P2M middle leafs at the early bootup stage, irregardless of this alignment check we need some means of doing that. For that we provide the new argument. Signed-off-by: Konrad Rzeszutek Wilk --- arch/x86/xen/p2m.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/arch/x86/xen/p2m.c b/arch/x86/xen/p2m.c index 3cc3afeb09a1..8b3a3958d120 100644 --- a/arch/x86/xen/p2m.c +++ b/arch/x86/xen/p2m.c @@ -499,7 +499,7 @@ static bool alloc_p2m(unsigned long pfn) return true; } -static bool __init early_alloc_p2m_middle(unsigned long pfn) +static bool __init early_alloc_p2m_middle(unsigned long pfn, bool check_boundary) { unsigned topidx, mididx, idx; @@ -508,7 +508,7 @@ static bool __init early_alloc_p2m_middle(unsigned long pfn) idx = p2m_index(pfn); /* Pfff.. No boundary cross-over, lets get out. */ - if (!idx) + if (!idx && check_boundary) return false; WARN(p2m_top[topidx][mididx] == p2m_identity, @@ -531,7 +531,7 @@ static bool __init early_alloc_p2m_middle(unsigned long pfn) p2m_top[topidx][mididx] = p2m; /* For save/restore we need to MFN of the P2M saved */ - + mid_mfn_p = p2m_top_mfn_p[topidx]; WARN(mid_mfn_p[mididx] != virt_to_mfn(p2m_missing), "P2M_TOP_P[%d][%d] != MFN of p2m_missing!\n", @@ -592,8 +592,8 @@ unsigned long __init set_phys_range_identity(unsigned long pfn_s, WARN_ON(!early_alloc_p2m(pfn)); } - early_alloc_p2m_middle(pfn_s); - early_alloc_p2m_middle(pfn_e); + early_alloc_p2m_middle(pfn_s, true); + early_alloc_p2m_middle(pfn_e, true); for (pfn = pfn_s; pfn < pfn_e; pfn++) if (!__set_phys_to_machine(pfn, IDENTITY_FRAME(pfn))) -- cgit v1.2.3 From d5096850b47424fb0f1c6a75b8f7184f7169319a Mon Sep 17 00:00:00 2001 From: Konrad Rzeszutek Wilk Date: Fri, 30 Mar 2012 14:16:49 -0400 Subject: xen/p2m: Collapse early_alloc_p2m_middle redundant checks. At the start of the function we were checking for idx != 0 and bailing out. And later calling extend_brk if idx != 0. That is unnecessary so remove that checks. Signed-off-by: Konrad Rzeszutek Wilk --- arch/x86/xen/p2m.c | 25 ++++++++++++------------- 1 file changed, 12 insertions(+), 13 deletions(-) diff --git a/arch/x86/xen/p2m.c b/arch/x86/xen/p2m.c index 8b3a3958d120..952edefcedb3 100644 --- a/arch/x86/xen/p2m.c +++ b/arch/x86/xen/p2m.c @@ -502,6 +502,8 @@ static bool alloc_p2m(unsigned long pfn) static bool __init early_alloc_p2m_middle(unsigned long pfn, bool check_boundary) { unsigned topidx, mididx, idx; + unsigned long *p2m; + unsigned long *mid_mfn_p; topidx = p2m_top_index(pfn); mididx = p2m_mid_index(pfn); @@ -522,24 +524,21 @@ static bool __init early_alloc_p2m_middle(unsigned long pfn, bool check_boundary return false; /* Boundary cross-over for the edges: */ - if (idx) { - unsigned long *p2m = extend_brk(PAGE_SIZE, PAGE_SIZE); - unsigned long *mid_mfn_p; + p2m = extend_brk(PAGE_SIZE, PAGE_SIZE); - p2m_init(p2m); + p2m_init(p2m); - p2m_top[topidx][mididx] = p2m; + p2m_top[topidx][mididx] = p2m; - /* For save/restore we need to MFN of the P2M saved */ + /* For save/restore we need to MFN of the P2M saved */ - mid_mfn_p = p2m_top_mfn_p[topidx]; - WARN(mid_mfn_p[mididx] != virt_to_mfn(p2m_missing), - "P2M_TOP_P[%d][%d] != MFN of p2m_missing!\n", - topidx, mididx); - mid_mfn_p[mididx] = virt_to_mfn(p2m); + mid_mfn_p = p2m_top_mfn_p[topidx]; + WARN(mid_mfn_p[mididx] != virt_to_mfn(p2m_missing), + "P2M_TOP_P[%d][%d] != MFN of p2m_missing!\n", + topidx, mididx); + mid_mfn_p[mididx] = virt_to_mfn(p2m); - } - return idx != 0; + return true; } static bool __init early_alloc_p2m(unsigned long pfn) -- cgit v1.2.3 From 940713bb2ce3033f468a220094a07250a2f69bdd Mon Sep 17 00:00:00 2001 From: Konrad Rzeszutek Wilk Date: Fri, 30 Mar 2012 14:33:14 -0400 Subject: xen/p2m: An early bootup variant of set_phys_to_machine During early bootup we can't use alloc_page, so to allocate leaf pages in the P2M we need to use extend_brk. For that we are utilizing the early_alloc_p2m and early_alloc_p2m_middle functions to do the job for us. This function follows the same logic as set_phys_to_machine. Signed-off-by: Konrad Rzeszutek Wilk --- arch/x86/include/asm/xen/page.h | 1 + arch/x86/xen/p2m.c | 15 +++++++++++++++ 2 files changed, 16 insertions(+) diff --git a/arch/x86/include/asm/xen/page.h b/arch/x86/include/asm/xen/page.h index c34f96c2f7a0..93971e841dd5 100644 --- a/arch/x86/include/asm/xen/page.h +++ b/arch/x86/include/asm/xen/page.h @@ -44,6 +44,7 @@ extern unsigned long machine_to_phys_nr; extern unsigned long get_phys_to_machine(unsigned long pfn); extern bool set_phys_to_machine(unsigned long pfn, unsigned long mfn); +extern bool __init early_set_phys_to_machine(unsigned long pfn, unsigned long mfn); extern bool __set_phys_to_machine(unsigned long pfn, unsigned long mfn); extern unsigned long set_phys_range_identity(unsigned long pfn_s, unsigned long pfn_e); diff --git a/arch/x86/xen/p2m.c b/arch/x86/xen/p2m.c index 952edefcedb3..ffd08c414e91 100644 --- a/arch/x86/xen/p2m.c +++ b/arch/x86/xen/p2m.c @@ -570,6 +570,21 @@ static bool __init early_alloc_p2m(unsigned long pfn) } return true; } +bool __init early_set_phys_to_machine(unsigned long pfn, unsigned long mfn) +{ + if (unlikely(!__set_phys_to_machine(pfn, mfn))) { + if (!early_alloc_p2m(pfn)) + return false; + + if (!early_alloc_p2m_middle(pfn, false /* boundary crossover OK!*/)) + return false; + + if (!__set_phys_to_machine(pfn, mfn)) + return false; + } + + return true; +} unsigned long __init set_phys_range_identity(unsigned long pfn_s, unsigned long pfn_e) { -- cgit v1.2.3 From 9fe2a7015393dc0203ac39242ae9c89038994f3c Mon Sep 17 00:00:00 2001 From: Srivatsa Vaddagiri Date: Fri, 23 Mar 2012 13:36:28 +0530 Subject: debugfs: Add support to print u32 array in debugfs Move the code from Xen to debugfs to make the code common for other users as well. Accked-by: Greg Kroah-Hartman Signed-off-by: Srivatsa Vaddagiri Signed-off-by: Suzuki Poulose [v1: Fixed rebase issues] [v2: Fixed PPC compile issues] Signed-off-by: Raghavendra K T Signed-off-by: Konrad Rzeszutek Wilk --- arch/x86/xen/debugfs.c | 104 --------------------------------------- arch/x86/xen/debugfs.h | 4 -- arch/x86/xen/spinlock.c | 12 ++--- fs/debugfs/file.c | 128 ++++++++++++++++++++++++++++++++++++++++++++++++ include/linux/debugfs.h | 11 +++++ 5 files changed, 145 insertions(+), 114 deletions(-) diff --git a/arch/x86/xen/debugfs.c b/arch/x86/xen/debugfs.c index ef1db1900d86..c8377fb26cdf 100644 --- a/arch/x86/xen/debugfs.c +++ b/arch/x86/xen/debugfs.c @@ -19,107 +19,3 @@ struct dentry * __init xen_init_debugfs(void) return d_xen_debug; } -struct array_data -{ - void *array; - unsigned elements; -}; - -static int u32_array_open(struct inode *inode, struct file *file) -{ - file->private_data = NULL; - return nonseekable_open(inode, file); -} - -static size_t format_array(char *buf, size_t bufsize, const char *fmt, - u32 *array, unsigned array_size) -{ - size_t ret = 0; - unsigned i; - - for(i = 0; i < array_size; i++) { - size_t len; - - len = snprintf(buf, bufsize, fmt, array[i]); - len++; /* ' ' or '\n' */ - ret += len; - - if (buf) { - buf += len; - bufsize -= len; - buf[-1] = (i == array_size-1) ? '\n' : ' '; - } - } - - ret++; /* \0 */ - if (buf) - *buf = '\0'; - - return ret; -} - -static char *format_array_alloc(const char *fmt, u32 *array, unsigned array_size) -{ - size_t len = format_array(NULL, 0, fmt, array, array_size); - char *ret; - - ret = kmalloc(len, GFP_KERNEL); - if (ret == NULL) - return NULL; - - format_array(ret, len, fmt, array, array_size); - return ret; -} - -static ssize_t u32_array_read(struct file *file, char __user *buf, size_t len, - loff_t *ppos) -{ - struct inode *inode = file->f_path.dentry->d_inode; - struct array_data *data = inode->i_private; - size_t size; - - if (*ppos == 0) { - if (file->private_data) { - kfree(file->private_data); - file->private_data = NULL; - } - - file->private_data = format_array_alloc("%u", data->array, data->elements); - } - - size = 0; - if (file->private_data) - size = strlen(file->private_data); - - return simple_read_from_buffer(buf, len, ppos, file->private_data, size); -} - -static int xen_array_release(struct inode *inode, struct file *file) -{ - kfree(file->private_data); - - return 0; -} - -static const struct file_operations u32_array_fops = { - .owner = THIS_MODULE, - .open = u32_array_open, - .release= xen_array_release, - .read = u32_array_read, - .llseek = no_llseek, -}; - -struct dentry *xen_debugfs_create_u32_array(const char *name, umode_t mode, - struct dentry *parent, - u32 *array, unsigned elements) -{ - struct array_data *data = kmalloc(sizeof(*data), GFP_KERNEL); - - if (data == NULL) - return NULL; - - data->array = array; - data->elements = elements; - - return debugfs_create_file(name, mode, parent, data, &u32_array_fops); -} diff --git a/arch/x86/xen/debugfs.h b/arch/x86/xen/debugfs.h index 78d25499be5b..12ebf3325c7b 100644 --- a/arch/x86/xen/debugfs.h +++ b/arch/x86/xen/debugfs.h @@ -3,8 +3,4 @@ struct dentry * __init xen_init_debugfs(void); -struct dentry *xen_debugfs_create_u32_array(const char *name, umode_t mode, - struct dentry *parent, - u32 *array, unsigned elements); - #endif /* _XEN_DEBUGFS_H */ diff --git a/arch/x86/xen/spinlock.c b/arch/x86/xen/spinlock.c index d69cc6c3f808..83e866d714ce 100644 --- a/arch/x86/xen/spinlock.c +++ b/arch/x86/xen/spinlock.c @@ -440,12 +440,12 @@ static int __init xen_spinlock_debugfs(void) debugfs_create_u64("time_total", 0444, d_spin_debug, &spinlock_stats.time_total); - xen_debugfs_create_u32_array("histo_total", 0444, d_spin_debug, - spinlock_stats.histo_spin_total, HISTO_BUCKETS + 1); - xen_debugfs_create_u32_array("histo_spinning", 0444, d_spin_debug, - spinlock_stats.histo_spin_spinning, HISTO_BUCKETS + 1); - xen_debugfs_create_u32_array("histo_blocked", 0444, d_spin_debug, - spinlock_stats.histo_spin_blocked, HISTO_BUCKETS + 1); + debugfs_create_u32_array("histo_total", 0444, d_spin_debug, + spinlock_stats.histo_spin_total, HISTO_BUCKETS + 1); + debugfs_create_u32_array("histo_spinning", 0444, d_spin_debug, + spinlock_stats.histo_spin_spinning, HISTO_BUCKETS + 1); + debugfs_create_u32_array("histo_blocked", 0444, d_spin_debug, + spinlock_stats.histo_spin_blocked, HISTO_BUCKETS + 1); return 0; } diff --git a/fs/debugfs/file.c b/fs/debugfs/file.c index 5dfafdd1dbd3..2340f6978d6e 100644 --- a/fs/debugfs/file.c +++ b/fs/debugfs/file.c @@ -20,6 +20,7 @@ #include #include #include +#include static ssize_t default_read_file(struct file *file, char __user *buf, size_t count, loff_t *ppos) @@ -520,6 +521,133 @@ struct dentry *debugfs_create_blob(const char *name, umode_t mode, } EXPORT_SYMBOL_GPL(debugfs_create_blob); +struct array_data { + void *array; + u32 elements; +}; + +static int u32_array_open(struct inode *inode, struct file *file) +{ + file->private_data = NULL; + return nonseekable_open(inode, file); +} + +static size_t format_array(char *buf, size_t bufsize, const char *fmt, + u32 *array, u32 array_size) +{ + size_t ret = 0; + u32 i; + + for (i = 0; i < array_size; i++) { + size_t len; + + len = snprintf(buf, bufsize, fmt, array[i]); + len++; /* ' ' or '\n' */ + ret += len; + + if (buf) { + buf += len; + bufsize -= len; + buf[-1] = (i == array_size-1) ? '\n' : ' '; + } + } + + ret++; /* \0 */ + if (buf) + *buf = '\0'; + + return ret; +} + +static char *format_array_alloc(const char *fmt, u32 *array, + u32 array_size) +{ + size_t len = format_array(NULL, 0, fmt, array, array_size); + char *ret; + + ret = kmalloc(len, GFP_KERNEL); + if (ret == NULL) + return NULL; + + format_array(ret, len, fmt, array, array_size); + return ret; +} + +static ssize_t u32_array_read(struct file *file, char __user *buf, size_t len, + loff_t *ppos) +{ + struct inode *inode = file->f_path.dentry->d_inode; + struct array_data *data = inode->i_private; + size_t size; + + if (*ppos == 0) { + if (file->private_data) { + kfree(file->private_data); + file->private_data = NULL; + } + + file->private_data = format_array_alloc("%u", data->array, + data->elements); + } + + size = 0; + if (file->private_data) + size = strlen(file->private_data); + + return simple_read_from_buffer(buf, len, ppos, + file->private_data, size); +} + +static int u32_array_release(struct inode *inode, struct file *file) +{ + kfree(file->private_data); + + return 0; +} + +static const struct file_operations u32_array_fops = { + .owner = THIS_MODULE, + .open = u32_array_open, + .release = u32_array_release, + .read = u32_array_read, + .llseek = no_llseek, +}; + +/** + * debugfs_create_u32_array - create a debugfs file that is used to read u32 + * array. + * @name: a pointer to a string containing the name of the file to create. + * @mode: the permission that the file should have. + * @parent: a pointer to the parent dentry for this file. This should be a + * directory dentry if set. If this parameter is %NULL, then the + * file will be created in the root of the debugfs filesystem. + * @array: u32 array that provides data. + * @elements: total number of elements in the array. + * + * This function creates a file in debugfs with the given name that exports + * @array as data. If the @mode variable is so set it can be read from. + * Writing is not supported. Seek within the file is also not supported. + * Once array is created its size can not be changed. + * + * The function returns a pointer to dentry on success. If debugfs is not + * enabled in the kernel, the value -%ENODEV will be returned. + */ +struct dentry *debugfs_create_u32_array(const char *name, umode_t mode, + struct dentry *parent, + u32 *array, u32 elements) +{ + struct array_data *data = kmalloc(sizeof(*data), GFP_KERNEL); + + if (data == NULL) + return NULL; + + data->array = array; + data->elements = elements; + + return debugfs_create_file(name, mode, parent, data, &u32_array_fops); +} +EXPORT_SYMBOL_GPL(debugfs_create_u32_array); + #ifdef CONFIG_HAS_IOMEM /* diff --git a/include/linux/debugfs.h b/include/linux/debugfs.h index ae36b72c22f3..66c434f5dd1e 100644 --- a/include/linux/debugfs.h +++ b/include/linux/debugfs.h @@ -93,6 +93,10 @@ struct dentry *debugfs_create_regset32(const char *name, umode_t mode, int debugfs_print_regs32(struct seq_file *s, const struct debugfs_reg32 *regs, int nregs, void __iomem *base, char *prefix); +struct dentry *debugfs_create_u32_array(const char *name, umode_t mode, + struct dentry *parent, + u32 *array, u32 elements); + bool debugfs_initialized(void); #else @@ -219,6 +223,13 @@ static inline bool debugfs_initialized(void) return false; } +static inline struct dentry *debugfs_create_u32_array(const char *name, umode_t mode, + struct dentry *parent, + u32 *array, u32 elements) +{ + return ERR_PTR(-ENODEV); +} + #endif #endif -- cgit v1.2.3 From 569ca5b3f94cd0b3295ec5943aa457cf4a4f6a3a Mon Sep 17 00:00:00 2001 From: Jan Beulich Date: Thu, 5 Apr 2012 16:10:07 +0100 Subject: xen/gnttab: add deferred freeing logic Rather than just leaking pages that can't be freed at the point where access permission for the backend domain gets revoked, put them on a list and run a timer to (infrequently) retry freeing them. (This can particularly happen when unloading a frontend driver when devices are still present, and the backend still has them in non-closed state or hasn't finished closing them yet.) Signed-off-by: Jan Beulich Signed-off-by: Konrad Rzeszutek Wilk --- drivers/xen/grant-table.c | 106 +++++++++++++++++++++++++++++++++++++++++----- 1 file changed, 96 insertions(+), 10 deletions(-) diff --git a/drivers/xen/grant-table.c b/drivers/xen/grant-table.c index b4d4eac761db..9f514bb561af 100644 --- a/drivers/xen/grant-table.c +++ b/drivers/xen/grant-table.c @@ -426,10 +426,8 @@ static int gnttab_end_foreign_access_ref_v1(grant_ref_t ref, int readonly) nflags = *pflags; do { flags = nflags; - if (flags & (GTF_reading|GTF_writing)) { - printk(KERN_ALERT "WARNING: g.e. still in use!\n"); + if (flags & (GTF_reading|GTF_writing)) return 0; - } } while ((nflags = sync_cmpxchg(pflags, flags, 0)) != flags); return 1; @@ -458,12 +456,103 @@ static int gnttab_end_foreign_access_ref_v2(grant_ref_t ref, int readonly) return 1; } -int gnttab_end_foreign_access_ref(grant_ref_t ref, int readonly) +static inline int _gnttab_end_foreign_access_ref(grant_ref_t ref, int readonly) { return gnttab_interface->end_foreign_access_ref(ref, readonly); } + +int gnttab_end_foreign_access_ref(grant_ref_t ref, int readonly) +{ + if (_gnttab_end_foreign_access_ref(ref, readonly)) + return 1; + pr_warn("WARNING: g.e. %#x still in use!\n", ref); + return 0; +} EXPORT_SYMBOL_GPL(gnttab_end_foreign_access_ref); +struct deferred_entry { + struct list_head list; + grant_ref_t ref; + bool ro; + uint16_t warn_delay; + struct page *page; +}; +static LIST_HEAD(deferred_list); +static void gnttab_handle_deferred(unsigned long); +static DEFINE_TIMER(deferred_timer, gnttab_handle_deferred, 0, 0); + +static void gnttab_handle_deferred(unsigned long unused) +{ + unsigned int nr = 10; + struct deferred_entry *first = NULL; + unsigned long flags; + + spin_lock_irqsave(&gnttab_list_lock, flags); + while (nr--) { + struct deferred_entry *entry + = list_first_entry(&deferred_list, + struct deferred_entry, list); + + if (entry == first) + break; + list_del(&entry->list); + spin_unlock_irqrestore(&gnttab_list_lock, flags); + if (_gnttab_end_foreign_access_ref(entry->ref, entry->ro)) { + put_free_entry(entry->ref); + if (entry->page) { + pr_debug("freeing g.e. %#x (pfn %#lx)\n", + entry->ref, page_to_pfn(entry->page)); + __free_page(entry->page); + } else + pr_info("freeing g.e. %#x\n", entry->ref); + kfree(entry); + entry = NULL; + } else { + if (!--entry->warn_delay) + pr_info("g.e. %#x still pending\n", + entry->ref); + if (!first) + first = entry; + } + spin_lock_irqsave(&gnttab_list_lock, flags); + if (entry) + list_add_tail(&entry->list, &deferred_list); + else if (list_empty(&deferred_list)) + break; + } + if (!list_empty(&deferred_list) && !timer_pending(&deferred_timer)) { + deferred_timer.expires = jiffies + HZ; + add_timer(&deferred_timer); + } + spin_unlock_irqrestore(&gnttab_list_lock, flags); +} + +static void gnttab_add_deferred(grant_ref_t ref, bool readonly, + struct page *page) +{ + struct deferred_entry *entry = kmalloc(sizeof(*entry), GFP_ATOMIC); + const char *what = KERN_WARNING "leaking"; + + if (entry) { + unsigned long flags; + + entry->ref = ref; + entry->ro = readonly; + entry->page = page; + entry->warn_delay = 60; + spin_lock_irqsave(&gnttab_list_lock, flags); + list_add_tail(&entry->list, &deferred_list); + if (!timer_pending(&deferred_timer)) { + deferred_timer.expires = jiffies + HZ; + add_timer(&deferred_timer); + } + spin_unlock_irqrestore(&gnttab_list_lock, flags); + what = KERN_DEBUG "deferring"; + } + printk("%s g.e. %#x (pfn %#lx)\n", + what, ref, page ? page_to_pfn(page) : -1); +} + void gnttab_end_foreign_access(grant_ref_t ref, int readonly, unsigned long page) { @@ -471,12 +560,9 @@ void gnttab_end_foreign_access(grant_ref_t ref, int readonly, put_free_entry(ref); if (page != 0) free_page(page); - } else { - /* XXX This needs to be fixed so that the ref and page are - placed on a list to be freed up later. */ - printk(KERN_WARNING - "WARNING: leaking g.e. and page still in use!\n"); - } + } else + gnttab_add_deferred(ref, readonly, + page ? virt_to_page(page) : NULL); } EXPORT_SYMBOL_GPL(gnttab_end_foreign_access); -- cgit v1.2.3 From ca1182387e57470460294ce1e39e2d5518809811 Mon Sep 17 00:00:00 2001 From: Konrad Rzeszutek Wilk Date: Fri, 30 Mar 2012 15:37:07 -0400 Subject: xen/setup: Only print "Freeing XXX-YYY pfn range: Z pages freed" if Z > 0 Otherwise we can get these meaningless: Freeing bad80-badf4 pfn range: 0 pages freed We also can do this for the summary ones - no point of printing "Set 0 page(s) to 1-1 mapping" Acked-by: David Vrabel [v1: Extended to the summary printks] Signed-off-by: Konrad Rzeszutek Wilk --- arch/x86/xen/setup.c | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) diff --git a/arch/x86/xen/setup.c b/arch/x86/xen/setup.c index 1ba8dff26753..7b0ab77b8479 100644 --- a/arch/x86/xen/setup.c +++ b/arch/x86/xen/setup.c @@ -114,8 +114,9 @@ static unsigned long __init xen_release_chunk(unsigned long start, len++; } } - printk(KERN_INFO "Freeing %lx-%lx pfn range: %lu pages freed\n", - start, end, len); + if (len) + printk(KERN_INFO "Freeing %lx-%lx pfn range: %lu pages freed\n", + start, end, len); return len; } @@ -162,8 +163,10 @@ static unsigned long __init xen_set_identity_and_release( } } - printk(KERN_INFO "Released %lu pages of unused memory\n", released); - printk(KERN_INFO "Set %ld page(s) to 1-1 mapping\n", identity); + if (released) + printk(KERN_INFO "Released %lu pages of unused memory\n", released); + if (identity) + printk(KERN_INFO "Set %ld page(s) to 1-1 mapping\n", identity); return released; } -- cgit v1.2.3 From 2e2fb75475c2fc74c98100f1468c8195fee49f3b Mon Sep 17 00:00:00 2001 From: Konrad Rzeszutek Wilk Date: Fri, 6 Apr 2012 10:07:11 -0400 Subject: xen/setup: Populate freed MFNs from non-RAM E820 entries and gaps to E820 RAM When the Xen hypervisor boots a PV kernel it hands it two pieces of information: nr_pages and a made up E820 entry. The nr_pages value defines the range from zero to nr_pages of PFNs which have a valid Machine Frame Number (MFN) underneath it. The E820 mirrors that (with the VGA hole): BIOS-provided physical RAM map: Xen: 0000000000000000 - 00000000000a0000 (usable) Xen: 00000000000a0000 - 0000000000100000 (reserved) Xen: 0000000000100000 - 0000000080800000 (usable) The fun comes when a PV guest that is run with a machine E820 - that can either be the initial domain or a PCI PV guest, where the E820 looks like the normal thing: BIOS-provided physical RAM map: Xen: 0000000000000000 - 000000000009e000 (usable) Xen: 000000000009ec00 - 0000000000100000 (reserved) Xen: 0000000000100000 - 0000000020000000 (usable) Xen: 0000000020000000 - 0000000020200000 (reserved) Xen: 0000000020200000 - 0000000040000000 (usable) Xen: 0000000040000000 - 0000000040200000 (reserved) Xen: 0000000040200000 - 00000000bad80000 (usable) Xen: 00000000bad80000 - 00000000badc9000 (ACPI NVS) .. With that overlaying the nr_pages directly on the E820 does not work as there are gaps and non-RAM regions that won't be used by the memory allocator. The 'xen_release_chunk' helps with that by punching holes in the P2M (PFN to MFN lookup tree) for those regions and tells us that: Freeing 20000-20200 pfn range: 512 pages freed Freeing 40000-40200 pfn range: 512 pages freed Freeing bad80-badf4 pfn range: 116 pages freed Freeing badf6-bae7f pfn range: 137 pages freed Freeing bb000-100000 pfn range: 282624 pages freed Released 283999 pages of unused memory Those 283999 pages are subtracted from the nr_pages and are returned to the hypervisor. The end result is that the initial domain boots with 1GB less memory as the nr_pages has been subtracted by the amount of pages residing within the PCI hole. It can balloon up to that if desired using 'xl mem-set 0 8092', but the balloon driver is not always compiled in for the initial domain. This patch, implements the populate hypercall (XENMEM_populate_physmap) which increases the the domain with the same amount of pages that were released. The other solution (that did not work) was to transplant the MFN in the P2M tree - the ones that were going to be freed were put in the E820_RAM regions past the nr_pages. But the modifications to the M2P array (the other side of creating PTEs) were not carried away. As the hypervisor is the only one capable of modifying that and the only two hypercalls that would do this are: the update_va_mapping (which won't work, as during initial bootup only PFNs up to nr_pages are mapped in the guest) or via the populate hypercall. The end result is that the kernel can now boot with the nr_pages without having to subtract the 283999 pages. On a 8GB machine, with various dom0_mem= parameters this is what we get: no dom0_mem -Memory: 6485264k/9435136k available (5817k kernel code, 1136060k absent, 1813812k reserved, 2899k data, 696k init) +Memory: 7619036k/9435136k available (5817k kernel code, 1136060k absent, 680040k reserved, 2899k data, 696k init) dom0_mem=3G -Memory: 2616536k/9435136k available (5817k kernel code, 1136060k absent, 5682540k reserved, 2899k data, 696k init) +Memory: 2703776k/9435136k available (5817k kernel code, 1136060k absent, 5595300k reserved, 2899k data, 696k init) dom0_mem=max:3G -Memory: 2696732k/4281724k available (5817k kernel code, 1136060k absent, 448932k reserved, 2899k data, 696k init) +Memory: 2702204k/4281724k available (5817k kernel code, 1136060k absent, 443460k reserved, 2899k data, 696k init) And the 'xm list' or 'xl list' now reflect what the dom0_mem= argument is. Acked-by: David Vrabel [v2: Use populate hypercall] [v3: Remove debug printks] [v4: Simplify code] Signed-off-by: Konrad Rzeszutek Wilk --- arch/x86/xen/setup.c | 116 +++++++++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 112 insertions(+), 4 deletions(-) diff --git a/arch/x86/xen/setup.c b/arch/x86/xen/setup.c index 7b0ab77b8479..710af36e6dfb 100644 --- a/arch/x86/xen/setup.c +++ b/arch/x86/xen/setup.c @@ -26,7 +26,6 @@ #include #include #include - #include "xen-ops.h" #include "vdso.h" @@ -120,7 +119,105 @@ static unsigned long __init xen_release_chunk(unsigned long start, return len; } +static unsigned long __init xen_populate_physmap(unsigned long start, + unsigned long end) +{ + struct xen_memory_reservation reservation = { + .address_bits = 0, + .extent_order = 0, + .domid = DOMID_SELF + }; + unsigned long len = 0; + int ret; + + for (pfn = start; pfn < end; pfn++) { + unsigned long frame; + + /* Make sure pfn does not exists to start with */ + if (pfn_to_mfn(pfn) != INVALID_P2M_ENTRY) + continue; + frame = pfn; + set_xen_guest_handle(reservation.extent_start, &frame); + reservation.nr_extents = 1; + + ret = HYPERVISOR_memory_op(XENMEM_populate_physmap, &reservation); + WARN(ret != 1, "Failed to populate pfn %lx err=%d\n", pfn, ret); + if (ret == 1) { + if (!early_set_phys_to_machine(pfn, frame)) { + set_xen_guest_handle(reservation.extent_start, &frame); + reservation.nr_extents = 1; + ret = HYPERVISOR_memory_op(XENMEM_decrease_reservation, + &reservation); + break; + } + len++; + } else + break; + } + if (len) + printk(KERN_INFO "Populated %lx-%lx pfn range: %lu pages added\n", + start, end, len); + return len; +} +static unsigned long __init xen_populate_chunk( + const struct e820entry *list, size_t map_size, + unsigned long max_pfn, unsigned long *last_pfn, + unsigned long credits_left) +{ + const struct e820entry *entry; + unsigned int i; + unsigned long done = 0; + unsigned long dest_pfn; + + for (i = 0, entry = list; i < map_size; i++, entry++) { + unsigned long credits = credits_left; + unsigned long s_pfn; + unsigned long e_pfn; + unsigned long pfns; + long capacity; + + if (credits <= 0) + break; + + if (entry->type != E820_RAM) + continue; + + e_pfn = PFN_UP(entry->addr + entry->size); + + /* We only care about E820 after the xen_start_info->nr_pages */ + if (e_pfn <= max_pfn) + continue; + + s_pfn = PFN_DOWN(entry->addr); + /* If the E820 falls within the nr_pages, we want to start + * at the nr_pages PFN. + * If that would mean going past the E820 entry, skip it + */ + if (s_pfn <= max_pfn) { + capacity = e_pfn - max_pfn; + dest_pfn = max_pfn; + } else { + /* last_pfn MUST be within E820_RAM regions */ + if (*last_pfn && e_pfn >= *last_pfn) + s_pfn = *last_pfn; + capacity = e_pfn - s_pfn; + dest_pfn = s_pfn; + } + /* If we had filled this E820_RAM entry, go to the next one. */ + if (capacity <= 0) + continue; + + if (credits > capacity) + credits = capacity; + + pfns = xen_populate_physmap(dest_pfn, dest_pfn + credits); + done += pfns; + credits_left -= pfns; + *last_pfn = (dest_pfn + pfns); + } + return done; +} static unsigned long __init xen_set_identity_and_release( const struct e820entry *list, size_t map_size, unsigned long nr_pages) { @@ -143,7 +240,6 @@ static unsigned long __init xen_set_identity_and_release( */ for (i = 0, entry = list; i < map_size; i++, entry++) { phys_addr_t end = entry->addr + entry->size; - if (entry->type == E820_RAM || i == map_size - 1) { unsigned long start_pfn = PFN_DOWN(start); unsigned long end_pfn = PFN_UP(end); @@ -220,7 +316,9 @@ char * __init xen_memory_setup(void) int rc; struct xen_memory_map memmap; unsigned long max_pages; + unsigned long last_pfn = 0; unsigned long extra_pages = 0; + unsigned long populated; int i; int op; @@ -260,8 +358,19 @@ char * __init xen_memory_setup(void) */ xen_released_pages = xen_set_identity_and_release( map, memmap.nr_entries, max_pfn); - extra_pages += xen_released_pages; + /* + * Populate back the non-RAM pages and E820 gaps that had been + * released. */ + populated = xen_populate_chunk(map, memmap.nr_entries, + max_pfn, &last_pfn, xen_released_pages); + + extra_pages += (xen_released_pages - populated); + + if (last_pfn > max_pfn) { + max_pfn = min(MAX_DOMAIN_PAGES, last_pfn); + mem_end = PFN_PHYS(max_pfn); + } /* * Clamp the amount of extra memory to a EXTRA_MEM_RATIO * factor the base size. On non-highmem systems, the base @@ -275,7 +384,6 @@ char * __init xen_memory_setup(void) */ extra_pages = min(EXTRA_MEM_RATIO * min(max_pfn, PFN_DOWN(MAXMEM)), extra_pages); - i = 0; while (i < memmap.nr_entries) { u64 addr = map[i].addr; -- cgit v1.2.3 From 96dc08b35c4af8cb5810450602590706f2593a5f Mon Sep 17 00:00:00 2001 From: Konrad Rzeszutek Wilk Date: Fri, 6 Apr 2012 16:10:20 -0400 Subject: xen/setup: Combine the two hypercall functions - since they are quite similar. They use the same set of arguments, so it is just the matter of using the proper hypercall. Acked-by: David Vrabel Signed-off-by: Konrad Rzeszutek Wilk --- arch/x86/xen/setup.c | 81 +++++++++++++++++++--------------------------------- 1 file changed, 30 insertions(+), 51 deletions(-) diff --git a/arch/x86/xen/setup.c b/arch/x86/xen/setup.c index 710af36e6dfb..30ac05a8d28f 100644 --- a/arch/x86/xen/setup.c +++ b/arch/x86/xen/setup.c @@ -83,8 +83,8 @@ static void __init xen_add_extra_mem(u64 start, u64 size) __set_phys_to_machine(pfn, INVALID_P2M_ENTRY); } -static unsigned long __init xen_release_chunk(unsigned long start, - unsigned long end) +static unsigned long __init xen_do_chunk(unsigned long start, + unsigned long end, bool release) { struct xen_memory_reservation reservation = { .address_bits = 0, @@ -95,60 +95,36 @@ static unsigned long __init xen_release_chunk(unsigned long start, unsigned long pfn; int ret; - for(pfn = start; pfn < end; pfn++) { - unsigned long mfn = pfn_to_mfn(pfn); - - /* Make sure pfn exists to start with */ - if (mfn == INVALID_P2M_ENTRY || mfn_to_pfn(mfn) != pfn) - continue; - - set_xen_guest_handle(reservation.extent_start, &mfn); - reservation.nr_extents = 1; - - ret = HYPERVISOR_memory_op(XENMEM_decrease_reservation, - &reservation); - WARN(ret != 1, "Failed to release pfn %lx err=%d\n", pfn, ret); - if (ret == 1) { - __set_phys_to_machine(pfn, INVALID_P2M_ENTRY); - len++; - } - } - if (len) - printk(KERN_INFO "Freeing %lx-%lx pfn range: %lu pages freed\n", - start, end, len); - - return len; -} -static unsigned long __init xen_populate_physmap(unsigned long start, - unsigned long end) -{ - struct xen_memory_reservation reservation = { - .address_bits = 0, - .extent_order = 0, - .domid = DOMID_SELF - }; - unsigned long len = 0; - int ret; - for (pfn = start; pfn < end; pfn++) { unsigned long frame; + unsigned long mfn = pfn_to_mfn(pfn); - /* Make sure pfn does not exists to start with */ - if (pfn_to_mfn(pfn) != INVALID_P2M_ENTRY) - continue; - - frame = pfn; + if (release) { + /* Make sure pfn exists to start with */ + if (mfn == INVALID_P2M_ENTRY || mfn_to_pfn(mfn) != pfn) + continue; + frame = mfn; + } else { + if (mfn != INVALID_P2M_ENTRY) + continue; + frame = pfn; + } set_xen_guest_handle(reservation.extent_start, &frame); reservation.nr_extents = 1; - ret = HYPERVISOR_memory_op(XENMEM_populate_physmap, &reservation); - WARN(ret != 1, "Failed to populate pfn %lx err=%d\n", pfn, ret); + ret = HYPERVISOR_memory_op(release ? XENMEM_decrease_reservation : XENMEM_populate_physmap, + &reservation); + WARN(ret != 1, "Failed to %s pfn %lx err=%d\n", + release ? "release" : "populate", pfn, ret); + if (ret == 1) { - if (!early_set_phys_to_machine(pfn, frame)) { + if (!early_set_phys_to_machine(pfn, release ? INVALID_P2M_ENTRY : frame)) { + if (release) + break; set_xen_guest_handle(reservation.extent_start, &frame); reservation.nr_extents = 1; ret = HYPERVISOR_memory_op(XENMEM_decrease_reservation, - &reservation); + &reservation); break; } len++; @@ -156,8 +132,11 @@ static unsigned long __init xen_populate_physmap(unsigned long start, break; } if (len) - printk(KERN_INFO "Populated %lx-%lx pfn range: %lu pages added\n", - start, end, len); + printk(KERN_INFO "%s %lx-%lx pfn range: %lu pages %s\n", + release ? "Freeing" : "Populating", + start, end, len, + release ? "freed" : "added"); + return len; } static unsigned long __init xen_populate_chunk( @@ -211,7 +190,7 @@ static unsigned long __init xen_populate_chunk( if (credits > capacity) credits = capacity; - pfns = xen_populate_physmap(dest_pfn, dest_pfn + credits); + pfns = xen_do_chunk(dest_pfn, dest_pfn + credits, false); done += pfns; credits_left -= pfns; *last_pfn = (dest_pfn + pfns); @@ -249,8 +228,8 @@ static unsigned long __init xen_set_identity_and_release( if (start_pfn < end_pfn) { if (start_pfn < nr_pages) - released += xen_release_chunk( - start_pfn, min(end_pfn, nr_pages)); + released += xen_do_chunk( + start_pfn, min(end_pfn, nr_pages), true); identity += set_phys_range_identity( start_pfn, end_pfn); -- cgit v1.2.3 From 83d51ab473dddde7df858015070ed22b84ebe9a9 Mon Sep 17 00:00:00 2001 From: David Vrabel Date: Thu, 3 May 2012 16:15:42 +0100 Subject: xen/setup: update VA mapping when releasing memory during setup In xen_memory_setup(), if a page that is being released has a VA mapping this must also be updated. Otherwise, the page will be not released completely -- it will still be referenced in Xen and won't be freed util the mapping is removed and this prevents it from being reallocated at a different PFN. This was already being done for the ISA memory region in xen_ident_map_ISA() but on many systems this was omitting a few pages as many systems marked a few pages below the ISA memory region as reserved in the e820 map. This fixes errors such as: (XEN) page_alloc.c:1148:d0 Over-allocation for domain 0: 2097153 > 2097152 (XEN) memory.c:133:d0 Could not allocate order=0 extent: id=0 memflags=0 (0 of 17) Signed-off-by: David Vrabel Signed-off-by: Konrad Rzeszutek Wilk --- arch/x86/xen/enlighten.c | 1 - arch/x86/xen/mmu.c | 23 ----------------------- arch/x86/xen/setup.c | 41 ++++++++++++++++++++++++++++++++++------- arch/x86/xen/xen-ops.h | 1 - 4 files changed, 34 insertions(+), 32 deletions(-) diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c index fe06bf4ef0e3..ac90e5629508 100644 --- a/arch/x86/xen/enlighten.c +++ b/arch/x86/xen/enlighten.c @@ -1308,7 +1308,6 @@ asmlinkage void __init xen_start_kernel(void) xen_raw_console_write("mapping kernel into physical memory\n"); pgd = xen_setup_kernel_pagetable(pgd, xen_start_info->nr_pages); - xen_ident_map_ISA(); /* Allocate and initialize top and mid mfn levels for p2m structure */ xen_build_mfn_list_list(); diff --git a/arch/x86/xen/mmu.c b/arch/x86/xen/mmu.c index 91dc2871e336..c9a351925a0c 100644 --- a/arch/x86/xen/mmu.c +++ b/arch/x86/xen/mmu.c @@ -1929,29 +1929,6 @@ static void xen_set_fixmap(unsigned idx, phys_addr_t phys, pgprot_t prot) #endif } -void __init xen_ident_map_ISA(void) -{ - unsigned long pa; - - /* - * If we're dom0, then linear map the ISA machine addresses into - * the kernel's address space. - */ - if (!xen_initial_domain()) - return; - - xen_raw_printk("Xen: setup ISA identity maps\n"); - - for (pa = ISA_START_ADDRESS; pa < ISA_END_ADDRESS; pa += PAGE_SIZE) { - pte_t pte = mfn_pte(PFN_DOWN(pa), PAGE_KERNEL_IO); - - if (HYPERVISOR_update_va_mapping(PAGE_OFFSET + pa, pte, 0)) - BUG(); - } - - xen_flush_tlb(); -} - static void __init xen_post_allocator_init(void) { pv_mmu_ops.set_pte = xen_set_pte; diff --git a/arch/x86/xen/setup.c b/arch/x86/xen/setup.c index 30ac05a8d28f..3ebba0753d38 100644 --- a/arch/x86/xen/setup.c +++ b/arch/x86/xen/setup.c @@ -139,6 +139,13 @@ static unsigned long __init xen_do_chunk(unsigned long start, return len; } + +static unsigned long __init xen_release_chunk(unsigned long start, + unsigned long end) +{ + return xen_do_chunk(start, end, true); +} + static unsigned long __init xen_populate_chunk( const struct e820entry *list, size_t map_size, unsigned long max_pfn, unsigned long *last_pfn, @@ -197,6 +204,29 @@ static unsigned long __init xen_populate_chunk( } return done; } + +static void __init xen_set_identity_and_release_chunk( + unsigned long start_pfn, unsigned long end_pfn, unsigned long nr_pages, + unsigned long *released, unsigned long *identity) +{ + unsigned long pfn; + + /* + * If the PFNs are currently mapped, the VA mapping also needs + * to be updated to be 1:1. + */ + for (pfn = start_pfn; pfn <= max_pfn_mapped && pfn < end_pfn; pfn++) + (void)HYPERVISOR_update_va_mapping( + (unsigned long)__va(pfn << PAGE_SHIFT), + mfn_pte(pfn, PAGE_KERNEL_IO), 0); + + if (start_pfn < nr_pages) + *released += xen_release_chunk( + start_pfn, min(end_pfn, nr_pages)); + + *identity += set_phys_range_identity(start_pfn, end_pfn); +} + static unsigned long __init xen_set_identity_and_release( const struct e820entry *list, size_t map_size, unsigned long nr_pages) { @@ -226,14 +256,11 @@ static unsigned long __init xen_set_identity_and_release( if (entry->type == E820_RAM) end_pfn = PFN_UP(entry->addr); - if (start_pfn < end_pfn) { - if (start_pfn < nr_pages) - released += xen_do_chunk( - start_pfn, min(end_pfn, nr_pages), true); + if (start_pfn < end_pfn) + xen_set_identity_and_release_chunk( + start_pfn, end_pfn, nr_pages, + &released, &identity); - identity += set_phys_range_identity( - start_pfn, end_pfn); - } start = end; } } diff --git a/arch/x86/xen/xen-ops.h b/arch/x86/xen/xen-ops.h index b095739ccd4c..506fa08d934a 100644 --- a/arch/x86/xen/xen-ops.h +++ b/arch/x86/xen/xen-ops.h @@ -28,7 +28,6 @@ void xen_setup_shared_info(void); void xen_build_mfn_list_list(void); void xen_setup_machphys_mapping(void); pgd_t *xen_setup_kernel_pagetable(pgd_t *pgd, unsigned long max_pfn); -void xen_ident_map_ISA(void); void xen_reserve_top(void); extern unsigned long xen_max_p2m_pfn; -- cgit v1.2.3 From f447d56d36af18c5104ff29dcb1327c0c0ac3634 Mon Sep 17 00:00:00 2001 From: Ben Guthro Date: Sat, 21 Apr 2012 00:11:04 +0800 Subject: xen: implement apic ipi interface Map native ipi vector to xen vector. Implement apic ipi interface with xen_send_IPI_one. Tested-by: Steven Noonan Signed-off-by: Ben Guthro Signed-off-by: Lin Ming Signed-off-by: Konrad Rzeszutek Wilk --- arch/x86/xen/enlighten.c | 9 ++++++ arch/x86/xen/smp.c | 81 +++++++++++++++++++++++++++++++++++++++++++++--- arch/x86/xen/smp.h | 12 +++++++ 3 files changed, 98 insertions(+), 4 deletions(-) create mode 100644 arch/x86/xen/smp.h diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c index 4f51bebac02c..1ed61c2bf633 100644 --- a/arch/x86/xen/enlighten.c +++ b/arch/x86/xen/enlighten.c @@ -74,6 +74,7 @@ #include "xen-ops.h" #include "mmu.h" +#include "smp.h" #include "multicalls.h" EXPORT_SYMBOL_GPL(hypercall_page); @@ -849,6 +850,14 @@ static void set_xen_basic_apic_ops(void) apic->icr_write = xen_apic_icr_write; apic->wait_icr_idle = xen_apic_wait_icr_idle; apic->safe_wait_icr_idle = xen_safe_apic_wait_icr_idle; + +#ifdef CONFIG_SMP + apic->send_IPI_allbutself = xen_send_IPI_allbutself; + apic->send_IPI_mask_allbutself = xen_send_IPI_mask_allbutself; + apic->send_IPI_mask = xen_send_IPI_mask; + apic->send_IPI_all = xen_send_IPI_all; + apic->send_IPI_self = xen_send_IPI_self; +#endif } #endif diff --git a/arch/x86/xen/smp.c b/arch/x86/xen/smp.c index 5fac6919b957..2dc6628c1520 100644 --- a/arch/x86/xen/smp.c +++ b/arch/x86/xen/smp.c @@ -465,8 +465,8 @@ static void xen_smp_send_reschedule(int cpu) xen_send_IPI_one(cpu, XEN_RESCHEDULE_VECTOR); } -static void xen_send_IPI_mask(const struct cpumask *mask, - enum ipi_vector vector) +static void __xen_send_IPI_mask(const struct cpumask *mask, + int vector) { unsigned cpu; @@ -478,7 +478,7 @@ static void xen_smp_send_call_function_ipi(const struct cpumask *mask) { int cpu; - xen_send_IPI_mask(mask, XEN_CALL_FUNCTION_VECTOR); + __xen_send_IPI_mask(mask, XEN_CALL_FUNCTION_VECTOR); /* Make sure other vcpus get a chance to run if they need to. */ for_each_cpu(cpu, mask) { @@ -491,10 +491,83 @@ static void xen_smp_send_call_function_ipi(const struct cpumask *mask) static void xen_smp_send_call_function_single_ipi(int cpu) { - xen_send_IPI_mask(cpumask_of(cpu), + __xen_send_IPI_mask(cpumask_of(cpu), XEN_CALL_FUNCTION_SINGLE_VECTOR); } +static inline int xen_map_vector(int vector) +{ + int xen_vector; + + switch (vector) { + case RESCHEDULE_VECTOR: + xen_vector = XEN_RESCHEDULE_VECTOR; + break; + case CALL_FUNCTION_VECTOR: + xen_vector = XEN_CALL_FUNCTION_VECTOR; + break; + case CALL_FUNCTION_SINGLE_VECTOR: + xen_vector = XEN_CALL_FUNCTION_SINGLE_VECTOR; + break; + default: + xen_vector = -1; + printk(KERN_ERR "xen: vector 0x%x is not implemented\n", + vector); + } + + return xen_vector; +} + +void xen_send_IPI_mask(const struct cpumask *mask, + int vector) +{ + int xen_vector = xen_map_vector(vector); + + if (xen_vector >= 0) + __xen_send_IPI_mask(mask, xen_vector); +} + +void xen_send_IPI_all(int vector) +{ + int xen_vector = xen_map_vector(vector); + + if (xen_vector >= 0) + __xen_send_IPI_mask(cpu_online_mask, xen_vector); +} + +void xen_send_IPI_self(int vector) +{ + int xen_vector = xen_map_vector(vector); + + if (xen_vector >= 0) + xen_send_IPI_one(smp_processor_id(), xen_vector); +} + +void xen_send_IPI_mask_allbutself(const struct cpumask *mask, + int vector) +{ + unsigned cpu; + unsigned int this_cpu = smp_processor_id(); + + if (!(num_online_cpus() > 1)) + return; + + for_each_cpu_and(cpu, mask, cpu_online_mask) { + if (this_cpu == cpu) + continue; + + xen_smp_send_call_function_single_ipi(cpu); + } +} + +void xen_send_IPI_allbutself(int vector) +{ + int xen_vector = xen_map_vector(vector); + + if (xen_vector >= 0) + xen_send_IPI_mask_allbutself(cpu_online_mask, xen_vector); +} + static irqreturn_t xen_call_function_interrupt(int irq, void *dev_id) { irq_enter(); diff --git a/arch/x86/xen/smp.h b/arch/x86/xen/smp.h new file mode 100644 index 000000000000..8981a76d081a --- /dev/null +++ b/arch/x86/xen/smp.h @@ -0,0 +1,12 @@ +#ifndef _XEN_SMP_H + +extern void xen_send_IPI_mask(const struct cpumask *mask, + int vector); +extern void xen_send_IPI_mask_allbutself(const struct cpumask *mask, + int vector); +extern void xen_send_IPI_allbutself(int vector); +extern void physflat_send_IPI_allbutself(int vector); +extern void xen_send_IPI_all(int vector); +extern void xen_send_IPI_self(int vector); + +#endif -- cgit v1.2.3 From 1ff2b0c303698e486f1e0886b4d9876200ef8ca5 Mon Sep 17 00:00:00 2001 From: Lin Ming Date: Sat, 21 Apr 2012 00:11:05 +0800 Subject: xen: implement IRQ_WORK_VECTOR handler Signed-off-by: Lin Ming Signed-off-by: Konrad Rzeszutek Wilk --- arch/x86/include/asm/xen/events.h | 1 + arch/x86/xen/smp.c | 30 ++++++++++++++++++++++++++++++ 2 files changed, 31 insertions(+) diff --git a/arch/x86/include/asm/xen/events.h b/arch/x86/include/asm/xen/events.h index 1df35417c412..cc146d51449e 100644 --- a/arch/x86/include/asm/xen/events.h +++ b/arch/x86/include/asm/xen/events.h @@ -6,6 +6,7 @@ enum ipi_vector { XEN_CALL_FUNCTION_VECTOR, XEN_CALL_FUNCTION_SINGLE_VECTOR, XEN_SPIN_UNLOCK_VECTOR, + XEN_IRQ_WORK_VECTOR, XEN_NR_IPIS, }; diff --git a/arch/x86/xen/smp.c b/arch/x86/xen/smp.c index 2dc6628c1520..3ec3f8eb19fc 100644 --- a/arch/x86/xen/smp.c +++ b/arch/x86/xen/smp.c @@ -16,6 +16,7 @@ #include #include #include +#include #include #include @@ -41,10 +42,12 @@ cpumask_var_t xen_cpu_initialized_map; static DEFINE_PER_CPU(int, xen_resched_irq); static DEFINE_PER_CPU(int, xen_callfunc_irq); static DEFINE_PER_CPU(int, xen_callfuncsingle_irq); +static DEFINE_PER_CPU(int, xen_irq_work); static DEFINE_PER_CPU(int, xen_debug_irq) = -1; static irqreturn_t xen_call_function_interrupt(int irq, void *dev_id); static irqreturn_t xen_call_function_single_interrupt(int irq, void *dev_id); +static irqreturn_t xen_irq_work_interrupt(int irq, void *dev_id); /* * Reschedule call back. @@ -143,6 +146,17 @@ static int xen_smp_intr_init(unsigned int cpu) goto fail; per_cpu(xen_callfuncsingle_irq, cpu) = rc; + callfunc_name = kasprintf(GFP_KERNEL, "irqwork%d", cpu); + rc = bind_ipi_to_irqhandler(XEN_IRQ_WORK_VECTOR, + cpu, + xen_irq_work_interrupt, + IRQF_DISABLED|IRQF_PERCPU|IRQF_NOBALANCING, + callfunc_name, + NULL); + if (rc < 0) + goto fail; + per_cpu(xen_irq_work, cpu) = rc; + return 0; fail: @@ -155,6 +169,8 @@ static int xen_smp_intr_init(unsigned int cpu) if (per_cpu(xen_callfuncsingle_irq, cpu) >= 0) unbind_from_irqhandler(per_cpu(xen_callfuncsingle_irq, cpu), NULL); + if (per_cpu(xen_irq_work, cpu) >= 0) + unbind_from_irqhandler(per_cpu(xen_irq_work, cpu), NULL); return rc; } @@ -509,6 +525,9 @@ static inline int xen_map_vector(int vector) case CALL_FUNCTION_SINGLE_VECTOR: xen_vector = XEN_CALL_FUNCTION_SINGLE_VECTOR; break; + case IRQ_WORK_VECTOR: + xen_vector = XEN_IRQ_WORK_VECTOR; + break; default: xen_vector = -1; printk(KERN_ERR "xen: vector 0x%x is not implemented\n", @@ -588,6 +607,16 @@ static irqreturn_t xen_call_function_single_interrupt(int irq, void *dev_id) return IRQ_HANDLED; } +static irqreturn_t xen_irq_work_interrupt(int irq, void *dev_id) +{ + irq_enter(); + irq_work_run(); + inc_irq_stat(apic_irq_work_irqs); + irq_exit(); + + return IRQ_HANDLED; +} + static const struct smp_ops xen_smp_ops __initconst = { .smp_prepare_boot_cpu = xen_smp_prepare_boot_cpu, .smp_prepare_cpus = xen_smp_prepare_cpus, @@ -634,6 +663,7 @@ static void xen_hvm_cpu_die(unsigned int cpu) unbind_from_irqhandler(per_cpu(xen_callfunc_irq, cpu), NULL); unbind_from_irqhandler(per_cpu(xen_debug_irq, cpu), NULL); unbind_from_irqhandler(per_cpu(xen_callfuncsingle_irq, cpu), NULL); + unbind_from_irqhandler(per_cpu(xen_irq_work, cpu), NULL); native_cpu_die(cpu); } -- cgit v1.2.3 From 211063dc159695bd6072c5393e9bc729481c6ede Mon Sep 17 00:00:00 2001 From: Konrad Rzeszutek Wilk Date: Thu, 8 Dec 2011 17:32:23 +0800 Subject: xen/acpi/sleep: Enable ACPI sleep via the __acpi_os_prepare_sleep Provide the registration callback to call in the Xen's ACPI sleep functionality. This means that during S3/S5 we make a hypercall XENPF_enter_acpi_sleep with the proper PM1A/PM1B registers. Based of Ke Yu's initial idea. [ From http://xenbits.xensource.com/linux-2.6.18-xen.hg change c68699484a65 ] [v1: Added Copyright and license] [v2: Added check if PM1A/B the 16-bits MSB contain something. The spec only uses 16-bits but might have more in future] Signed-off-by: Liang Tang Signed-off-by: Konrad Rzeszutek Wilk --- arch/x86/xen/enlighten.c | 3 +++ drivers/xen/Makefile | 2 +- drivers/xen/acpi.c | 62 ++++++++++++++++++++++++++++++++++++++++++++++++ include/xen/acpi.h | 58 ++++++++++++++++++++++++++++++++++++++++++++ 4 files changed, 124 insertions(+), 1 deletion(-) create mode 100644 drivers/xen/acpi.c create mode 100644 include/xen/acpi.h diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c index 1ed61c2bf633..eca90e5be1e7 100644 --- a/arch/x86/xen/enlighten.c +++ b/arch/x86/xen/enlighten.c @@ -42,6 +42,7 @@ #include #include #include +#include #include #include @@ -1373,6 +1374,8 @@ asmlinkage void __init xen_start_kernel(void) /* Make sure ACS will be enabled */ pci_request_acs(); + + xen_acpi_sleep_register(); } diff --git a/drivers/xen/Makefile b/drivers/xen/Makefile index 9adc5be57b13..fc3488631136 100644 --- a/drivers/xen/Makefile +++ b/drivers/xen/Makefile @@ -17,7 +17,7 @@ obj-$(CONFIG_XEN_SYS_HYPERVISOR) += sys-hypervisor.o obj-$(CONFIG_XEN_PVHVM) += platform-pci.o obj-$(CONFIG_XEN_TMEM) += tmem.o obj-$(CONFIG_SWIOTLB_XEN) += swiotlb-xen.o -obj-$(CONFIG_XEN_DOM0) += pci.o +obj-$(CONFIG_XEN_DOM0) += pci.o acpi.o obj-$(CONFIG_XEN_PCIDEV_BACKEND) += xen-pciback/ obj-$(CONFIG_XEN_PRIVCMD) += xen-privcmd.o obj-$(CONFIG_XEN_ACPI_PROCESSOR) += xen-acpi-processor.o diff --git a/drivers/xen/acpi.c b/drivers/xen/acpi.c new file mode 100644 index 000000000000..119d42a2bf57 --- /dev/null +++ b/drivers/xen/acpi.c @@ -0,0 +1,62 @@ +/****************************************************************************** + * acpi.c + * acpi file for domain 0 kernel + * + * Copyright (c) 2011 Konrad Rzeszutek Wilk + * Copyright (c) 2011 Yu Ke ke.yu@intel.com + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License version 2 + * as published by the Free Software Foundation; or, when distributed + * separately from the Linux kernel or incorporated into other + * software packages, subject to the following license: + * + * Permission is hereby granted, free of charge, to any person obtaining a copy + * of this source file (the "Software"), to deal in the Software without + * restriction, including without limitation the rights to use, copy, modify, + * merge, publish, distribute, sublicense, and/or sell copies of the Software, + * and to permit persons to whom the Software is furnished to do so, subject to + * the following conditions: + * + * The above copyright notice and this permission notice shall be included in + * all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE + * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING + * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS + * IN THE SOFTWARE. + */ + +#include +#include +#include +#include + +int xen_acpi_notify_hypervisor_state(u8 sleep_state, + u32 pm1a_cnt, u32 pm1b_cnt) +{ + struct xen_platform_op op = { + .cmd = XENPF_enter_acpi_sleep, + .interface_version = XENPF_INTERFACE_VERSION, + .u = { + .enter_acpi_sleep = { + .pm1a_cnt_val = (u16)pm1a_cnt, + .pm1b_cnt_val = (u16)pm1b_cnt, + .sleep_state = sleep_state, + }, + }, + }; + + if ((pm1a_cnt & 0xffff0000) || (pm1b_cnt & 0xffff0000)) { + WARN(1, "Using more than 16bits of PM1A/B 0x%x/0x%x!" + "Email xen-devel@lists.xensource.com Thank you.\n", \ + pm1a_cnt, pm1b_cnt); + return -1; + } + + HYPERVISOR_dom0_op(&op); + return 1; +} diff --git a/include/xen/acpi.h b/include/xen/acpi.h new file mode 100644 index 000000000000..48a9c0171b65 --- /dev/null +++ b/include/xen/acpi.h @@ -0,0 +1,58 @@ +/****************************************************************************** + * acpi.h + * acpi file for domain 0 kernel + * + * Copyright (c) 2011 Konrad Rzeszutek Wilk + * Copyright (c) 2011 Yu Ke + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License version 2 + * as published by the Free Software Foundation; or, when distributed + * separately from the Linux kernel or incorporated into other + * software packages, subject to the following license: + * + * Permission is hereby granted, free of charge, to any person obtaining a copy + * of this source file (the "Software"), to deal in the Software without + * restriction, including without limitation the rights to use, copy, modify, + * merge, publish, distribute, sublicense, and/or sell copies of the Software, + * and to permit persons to whom the Software is furnished to do so, subject to + * the following conditions: + * + * The above copyright notice and this permission notice shall be included in + * all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE + * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING + * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS + * IN THE SOFTWARE. + */ + +#ifndef _XEN_ACPI_H +#define _XEN_ACPI_H + +#include + +#ifdef CONFIG_XEN_DOM0 +#include +#include +#include + +int xen_acpi_notify_hypervisor_state(u8 sleep_state, + u32 pm1a_cnt, u32 pm1b_cnd); + +static inline void xen_acpi_sleep_register(void) +{ + if (xen_initial_domain()) + acpi_os_set_prepare_sleep( + &xen_acpi_notify_hypervisor_state); +} +#else +static inline void xen_acpi_sleep_register(void) +{ +} +#endif + +#endif /* _XEN_ACPI_H */ -- cgit v1.2.3 From f62805f1f30a40e354bd036b4cb799863a39be4b Mon Sep 17 00:00:00 2001 From: Stefano Stabellini Date: Tue, 24 Apr 2012 11:55:43 +0100 Subject: xen: enter/exit lazy_mmu_mode around m2p_override calls This patch is a significant performance improvement for the m2p_override: about 6% using the gntdev device. Each m2p_add/remove_override call issues a MULTI_grant_table_op and a __flush_tlb_single if kmap_op != NULL. Batching all the calls together is a great performance benefit because it means issuing one hypercall total rather than two hypercall per page. If paravirt_lazy_mode is set PARAVIRT_LAZY_MMU, all these calls are going to be batched together, otherwise they are issued one at a time. Adding arch_enter_lazy_mmu_mode/arch_leave_lazy_mmu_mode around the m2p_add/remove_override calls forces paravirt_lazy_mode to PARAVIRT_LAZY_MMU, therefore makes sure that they are always batched. However it is not safe to call arch_enter_lazy_mmu_mode if we are in interrupt context or if we are already in PARAVIRT_LAZY_MMU mode, so check for both conditions before doing so. Changes in v4: - rebased on 3.4-rc4: all the m2p_override users call gnttab_unmap_refs and gnttab_map_refs; - check whether we are in interrupt context and the lazy_mode we are in before calling arch_enter/leave_lazy_mmu_mode. Changes in v3: - do not call arch_enter/leave_lazy_mmu_mode in xen_blkbk_unmap, that can be called in interrupt context. Signed-off-by: Stefano Stabellini [v5: s/int lazy/bool lazy/] Signed-off-by: Konrad Rzeszutek Wilk --- drivers/xen/grant-table.c | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+) diff --git a/drivers/xen/grant-table.c b/drivers/xen/grant-table.c index 9f514bb561af..487e468f9ded 100644 --- a/drivers/xen/grant-table.c +++ b/drivers/xen/grant-table.c @@ -38,6 +38,7 @@ #include #include #include +#include #include #include @@ -827,6 +828,7 @@ int gnttab_map_refs(struct gnttab_map_grant_ref *map_ops, struct page **pages, unsigned int count) { int i, ret; + bool lazy = false; pte_t *pte; unsigned long mfn; @@ -837,6 +839,11 @@ int gnttab_map_refs(struct gnttab_map_grant_ref *map_ops, if (xen_feature(XENFEAT_auto_translated_physmap)) return ret; + if (!in_interrupt() && paravirt_get_lazy_mode() == PARAVIRT_LAZY_NONE) { + arch_enter_lazy_mmu_mode(); + lazy = true; + } + for (i = 0; i < count; i++) { /* Do not add to override if the map failed. */ if (map_ops[i].status) @@ -855,6 +862,9 @@ int gnttab_map_refs(struct gnttab_map_grant_ref *map_ops, return ret; } + if (lazy) + arch_leave_lazy_mmu_mode(); + return ret; } EXPORT_SYMBOL_GPL(gnttab_map_refs); @@ -863,6 +873,7 @@ int gnttab_unmap_refs(struct gnttab_unmap_grant_ref *unmap_ops, struct page **pages, unsigned int count, bool clear_pte) { int i, ret; + bool lazy = false; ret = HYPERVISOR_grant_table_op(GNTTABOP_unmap_grant_ref, unmap_ops, count); if (ret) @@ -871,12 +882,20 @@ int gnttab_unmap_refs(struct gnttab_unmap_grant_ref *unmap_ops, if (xen_feature(XENFEAT_auto_translated_physmap)) return ret; + if (!in_interrupt() && paravirt_get_lazy_mode() == PARAVIRT_LAZY_NONE) { + arch_enter_lazy_mmu_mode(); + lazy = true; + } + for (i = 0; i < count; i++) { ret = m2p_remove_override(pages[i], clear_pte); if (ret) return ret; } + if (lazy) + arch_leave_lazy_mmu_mode(); + return ret; } EXPORT_SYMBOL_GPL(gnttab_unmap_refs); -- cgit v1.2.3 From 2f1bd67d544d3c086fb5101513f4b6c8f4291b43 Mon Sep 17 00:00:00 2001 From: Konrad Rzeszutek Wilk Date: Mon, 21 May 2012 09:19:38 -0400 Subject: xen/smp: unbind irqworkX when unplugging vCPUs. The git commit 1ff2b0c303698e486f1e0886b4d9876200ef8ca5 "xen: implement IRQ_WORK_VECTOR handler" added the functionality to have a per-cpu "irqworkX" for the IPI APIC functionality. However it missed the unbind when a vCPU is unplugged resulting in an orphaned per-cpu interrupt line for unplugged vCPU: 30: 216 0 xen-dyn-event hvc_console 31: 810 4 xen-dyn-event eth0 32: 29 0 xen-dyn-event blkif - 36: 0 0 xen-percpu-ipi irqwork2 - 37: 287 0 xen-dyn-event xenbus + 36: 287 0 xen-dyn-event xenbus NMI: 0 0 Non-maskable interrupts LOC: 0 0 Local timer interrupts SPU: 0 0 Spurious interrupts Signed-off-by: Konrad Rzeszutek Wilk --- arch/x86/xen/smp.c | 1 + 1 file changed, 1 insertion(+) diff --git a/arch/x86/xen/smp.c b/arch/x86/xen/smp.c index 3ec3f8eb19fc..ce9e98b1e69c 100644 --- a/arch/x86/xen/smp.c +++ b/arch/x86/xen/smp.c @@ -419,6 +419,7 @@ static void xen_cpu_die(unsigned int cpu) unbind_from_irqhandler(per_cpu(xen_callfunc_irq, cpu), NULL); unbind_from_irqhandler(per_cpu(xen_debug_irq, cpu), NULL); unbind_from_irqhandler(per_cpu(xen_callfuncsingle_irq, cpu), NULL); + unbind_from_irqhandler(per_cpu(xen_irq_work, cpu), NULL); xen_uninit_lock_cpu(cpu); xen_teardown_timer(cpu); -- cgit v1.2.3 From d2fb4c51c7471a23f0a95526b624c14cec62603d Mon Sep 17 00:00:00 2001 From: Daniel De Graaf Date: Tue, 8 May 2012 09:46:57 -0400 Subject: xenbus: Add support for xenbus backend in stub domain Add an ioctl to the /dev/xen/xenbus_backend device allowing the xenbus backend to be started after the kernel has booted. This allows xenstore to run in a different domain from the dom0. Signed-off-by: Daniel De Graaf Signed-off-by: Konrad Rzeszutek Wilk --- drivers/xen/xenbus/xenbus_comms.c | 6 ++++ drivers/xen/xenbus/xenbus_comms.h | 1 + drivers/xen/xenbus/xenbus_dev_backend.c | 51 +++++++++++++++++++++++++++++++++ include/xen/grant_table.h | 2 ++ include/xen/xenbus_dev.h | 3 ++ 5 files changed, 63 insertions(+) diff --git a/drivers/xen/xenbus/xenbus_comms.c b/drivers/xen/xenbus/xenbus_comms.c index 2eff7a6aaa20..52fe7ad07666 100644 --- a/drivers/xen/xenbus/xenbus_comms.c +++ b/drivers/xen/xenbus/xenbus_comms.c @@ -234,3 +234,9 @@ int xb_init_comms(void) return 0; } + +void xb_deinit_comms(void) +{ + unbind_from_irqhandler(xenbus_irq, &xb_waitq); + xenbus_irq = 0; +} diff --git a/drivers/xen/xenbus/xenbus_comms.h b/drivers/xen/xenbus/xenbus_comms.h index 6e42800fa499..c8abd3b8a6c4 100644 --- a/drivers/xen/xenbus/xenbus_comms.h +++ b/drivers/xen/xenbus/xenbus_comms.h @@ -35,6 +35,7 @@ int xs_init(void); int xb_init_comms(void); +void xb_deinit_comms(void); /* Low level routines. */ int xb_write(const void *data, unsigned len); diff --git a/drivers/xen/xenbus/xenbus_dev_backend.c b/drivers/xen/xenbus/xenbus_dev_backend.c index 3d3be78c1093..be738c43104b 100644 --- a/drivers/xen/xenbus/xenbus_dev_backend.c +++ b/drivers/xen/xenbus/xenbus_dev_backend.c @@ -8,7 +8,11 @@ #include #include +#include #include +#include +#include +#include #include "xenbus_comms.h" @@ -22,6 +26,50 @@ static int xenbus_backend_open(struct inode *inode, struct file *filp) return nonseekable_open(inode, filp); } +static long xenbus_alloc(domid_t domid) +{ + struct evtchn_alloc_unbound arg; + int err = -EEXIST; + + xs_suspend(); + + /* If xenstored_ready is nonzero, that means we have already talked to + * xenstore and set up watches. These watches will be restored by + * xs_resume, but that requires communication over the port established + * below that is not visible to anyone until the ioctl returns. + * + * This can be resolved by splitting the ioctl into two parts + * (postponing the resume until xenstored is active) but this is + * unnecessarily complex for the intended use where xenstored is only + * started once - so return -EEXIST if it's already running. + */ + if (xenstored_ready) + goto out_err; + + gnttab_grant_foreign_access_ref(GNTTAB_RESERVED_XENSTORE, domid, + virt_to_mfn(xen_store_interface), 0 /* writable */); + + arg.dom = DOMID_SELF; + arg.remote_dom = domid; + + err = HYPERVISOR_event_channel_op(EVTCHNOP_alloc_unbound, &arg); + if (err) + goto out_err; + + if (xen_store_evtchn > 0) + xb_deinit_comms(); + + xen_store_evtchn = arg.port; + + xs_resume(); + + return arg.port; + + out_err: + xs_suspend_cancel(); + return err; +} + static long xenbus_backend_ioctl(struct file *file, unsigned int cmd, unsigned long data) { if (!capable(CAP_SYS_ADMIN)) @@ -33,6 +81,9 @@ static long xenbus_backend_ioctl(struct file *file, unsigned int cmd, unsigned l return xen_store_evtchn; return -ENODEV; + case IOCTL_XENBUS_BACKEND_SETUP: + return xenbus_alloc(data); + default: return -ENOTTY; } diff --git a/include/xen/grant_table.h b/include/xen/grant_table.h index 15f8a00ff003..11e27c3af3cb 100644 --- a/include/xen/grant_table.h +++ b/include/xen/grant_table.h @@ -46,6 +46,8 @@ #include +#define GNTTAB_RESERVED_XENSTORE 1 + /* NR_GRANT_FRAMES must be less than or equal to that configured in Xen */ #define NR_GRANT_FRAMES 4 diff --git a/include/xen/xenbus_dev.h b/include/xen/xenbus_dev.h index ac5f0fe47ed9..bbee8c6a349d 100644 --- a/include/xen/xenbus_dev.h +++ b/include/xen/xenbus_dev.h @@ -38,4 +38,7 @@ #define IOCTL_XENBUS_BACKEND_EVTCHN \ _IOC(_IOC_NONE, 'B', 0, 0) +#define IOCTL_XENBUS_BACKEND_SETUP \ + _IOC(_IOC_NONE, 'B', 1, 0) + #endif /* __LINUX_XEN_XENBUS_DEV_H__ */ -- cgit v1.2.3 From d79d5959a023fd637e90ed1ff6547ff09d19396b Mon Sep 17 00:00:00 2001 From: Jana Saout Date: Tue, 15 May 2012 12:34:46 +0200 Subject: xen: Add selfballoning memory reservation tunable. Currently, the memory target in the Xen selfballooning driver is mainly driven by the value of "Committed_AS". However, there are cases in which it is desirable to assign additional memory to be available for the kernel, e.g. for local caches (which are not covered by cleancache), e.g. dcache and inode caches. This adds an additional tunable in the selfballooning driver (accessible via sysfs) which allows the user to specify an additional constant amount of memory to be reserved by the selfballoning driver for the local domain. Signed-off-by: Jana Saout Acked-by: Dan Magenheimer Signed-off-by: Konrad Rzeszutek Wilk --- drivers/xen/xen-selfballoon.c | 34 +++++++++++++++++++++++++++++++++- 1 file changed, 33 insertions(+), 1 deletion(-) diff --git a/drivers/xen/xen-selfballoon.c b/drivers/xen/xen-selfballoon.c index 146c94897016..7d041cb6da26 100644 --- a/drivers/xen/xen-selfballoon.c +++ b/drivers/xen/xen-selfballoon.c @@ -105,6 +105,12 @@ static unsigned int selfballoon_interval __read_mostly = 5; */ static unsigned int selfballoon_min_usable_mb; +/* + * Amount of RAM in MB to add to the target number of pages. + * Can be used to reserve some more room for caches and the like. + */ +static unsigned int selfballoon_reserved_mb; + static void selfballoon_process(struct work_struct *work); static DECLARE_DELAYED_WORK(selfballoon_worker, selfballoon_process); @@ -217,7 +223,8 @@ static void selfballoon_process(struct work_struct *work) cur_pages = totalram_pages; tgt_pages = cur_pages; /* default is no change */ goal_pages = percpu_counter_read_positive(&vm_committed_as) + - totalreserve_pages; + totalreserve_pages + + MB2PAGES(selfballoon_reserved_mb); #ifdef CONFIG_FRONTSWAP /* allow space for frontswap pages to be repatriated */ if (frontswap_selfshrinking && frontswap_enabled) @@ -397,6 +404,30 @@ static DEVICE_ATTR(selfballoon_min_usable_mb, S_IRUGO | S_IWUSR, show_selfballoon_min_usable_mb, store_selfballoon_min_usable_mb); +SELFBALLOON_SHOW(selfballoon_reserved_mb, "%d\n", + selfballoon_reserved_mb); + +static ssize_t store_selfballoon_reserved_mb(struct device *dev, + struct device_attribute *attr, + const char *buf, + size_t count) +{ + unsigned long val; + int err; + + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + err = strict_strtoul(buf, 10, &val); + if (err || val == 0) + return -EINVAL; + selfballoon_reserved_mb = val; + return count; +} + +static DEVICE_ATTR(selfballoon_reserved_mb, S_IRUGO | S_IWUSR, + show_selfballoon_reserved_mb, + store_selfballoon_reserved_mb); + #ifdef CONFIG_FRONTSWAP SELFBALLOON_SHOW(frontswap_selfshrinking, "%d\n", frontswap_selfshrinking); @@ -480,6 +511,7 @@ static struct attribute *selfballoon_attrs[] = { &dev_attr_selfballoon_downhysteresis.attr, &dev_attr_selfballoon_uphysteresis.attr, &dev_attr_selfballoon_min_usable_mb.attr, + &dev_attr_selfballoon_reserved_mb.attr, #ifdef CONFIG_FRONTSWAP &dev_attr_frontswap_selfshrinking.attr, &dev_attr_frontswap_hysteresis.attr, -- cgit v1.2.3 From 201a52bea928687b7557728b176ac4f8a37d5cbd Mon Sep 17 00:00:00 2001 From: Dan Carpenter Date: Tue, 15 May 2012 11:47:47 +0300 Subject: hvc_xen: NULL dereference on allocation failure If kzalloc() returns a NULL here, we pass a NULL to xencons_disconnect_backend() which will cause an Oops. Also I removed the __GFP_ZERO while I was at it since kzalloc() implies __GFP_ZERO. CC: stable@kernel.org Acked-by: Stefano Stabellini Signed-off-by: Dan Carpenter Signed-off-by: Konrad Rzeszutek Wilk --- drivers/tty/hvc/hvc_xen.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/tty/hvc/hvc_xen.c b/drivers/tty/hvc/hvc_xen.c index 83d5c88e7165..d3d91dae065c 100644 --- a/drivers/tty/hvc/hvc_xen.c +++ b/drivers/tty/hvc/hvc_xen.c @@ -430,9 +430,9 @@ static int __devinit xencons_probe(struct xenbus_device *dev, if (devid == 0) return -ENODEV; - info = kzalloc(sizeof(struct xencons_info), GFP_KERNEL | __GFP_ZERO); + info = kzalloc(sizeof(struct xencons_info), GFP_KERNEL); if (!info) - goto error_nomem; + return -ENOMEM; dev_set_drvdata(&dev->dev, info); info->xbdev = dev; info->vtermno = xenbus_devid_to_vtermno(devid); -- cgit v1.2.3 From 68c2c39a76b094e9b2773e5846424ea674bf2c46 Mon Sep 17 00:00:00 2001 From: Stefano Stabellini Date: Mon, 21 May 2012 16:54:10 +0100 Subject: xen: do not map the same GSI twice in PVHVM guests. PV on HVM guests map GSIs into event channels. At restore time the event channels are resumed by restore_pirqs. Device drivers might try to register the same GSI again through ACPI at restore time, but the GSI has already been mapped and bound by restore_pirqs. This patch detects these situations and avoids mapping the same GSI multiple times. Without this patch we get: (XEN) irq.c:2235: dom4: pirq 23 or emuirq 28 already mapped and waste a pirq. CC: stable@kernel.org Signed-off-by: Stefano Stabellini Signed-off-by: Konrad Rzeszutek Wilk --- arch/x86/pci/xen.c | 4 ++++ drivers/xen/events.c | 5 +++-- include/xen/events.h | 3 +++ 3 files changed, 10 insertions(+), 2 deletions(-) diff --git a/arch/x86/pci/xen.c b/arch/x86/pci/xen.c index 7415aa927913..56ab74989cf1 100644 --- a/arch/x86/pci/xen.c +++ b/arch/x86/pci/xen.c @@ -64,6 +64,10 @@ static int xen_register_pirq(u32 gsi, int gsi_override, int triggering, int shareable = 0; char *name; + irq = xen_irq_from_gsi(gsi); + if (irq > 0) + return irq; + if (set_pirq) pirq = gsi; diff --git a/drivers/xen/events.c b/drivers/xen/events.c index 4b33acd8ed4e..faae2f910ad2 100644 --- a/drivers/xen/events.c +++ b/drivers/xen/events.c @@ -611,7 +611,7 @@ static void disable_pirq(struct irq_data *data) disable_dynirq(data); } -static int find_irq_by_gsi(unsigned gsi) +int xen_irq_from_gsi(unsigned gsi) { struct irq_info *info; @@ -625,6 +625,7 @@ static int find_irq_by_gsi(unsigned gsi) return -1; } +EXPORT_SYMBOL_GPL(xen_irq_from_gsi); /* * Do not make any assumptions regarding the relationship between the @@ -644,7 +645,7 @@ int xen_bind_pirq_gsi_to_irq(unsigned gsi, mutex_lock(&irq_mapping_update_lock); - irq = find_irq_by_gsi(gsi); + irq = xen_irq_from_gsi(gsi); if (irq != -1) { printk(KERN_INFO "xen_map_pirq_gsi: returning irq %d for gsi %u\n", irq, gsi); diff --git a/include/xen/events.h b/include/xen/events.h index 0f773708e02c..04399b28e821 100644 --- a/include/xen/events.h +++ b/include/xen/events.h @@ -103,6 +103,9 @@ int xen_irq_from_pirq(unsigned pirq); /* Return the pirq allocated to the irq. */ int xen_pirq_from_irq(unsigned irq); +/* Return the irq allocated to the gsi */ +int xen_irq_from_gsi(unsigned gsi); + /* Determine whether to ignore this IRQ if it is passed to a guest. */ int xen_test_irq_shared(int irq); -- cgit v1.2.3