From 3482f2c52b77bf6596e24aae82e204a0603eba66 Mon Sep 17 00:00:00 2001 From: Grant Likely Date: Thu, 27 Mar 2014 17:18:55 -0700 Subject: of: Create of_console_check() for selecting a console specified in /chosen The devicetree has a binding for specifying the console device in the /chosen node, but the kernel doesn't use it consistently. This change adds an API for testing if a device node is a console, and adds a preferred console entry if it is. At the same time this patch removes the of_device_is_stdout_path() API since it is unused. Signed-off-by: Grant Likely Tested-by: Sascha Hauer --- include/linux/of.h | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'include/linux/of.h') diff --git a/include/linux/of.h b/include/linux/of.h index 196b34c1ef4..9d9734056e3 100644 --- a/include/linux/of.h +++ b/include/linux/of.h @@ -352,7 +352,7 @@ const __be32 *of_prop_next_u32(struct property *prop, const __be32 *cur, */ const char *of_prop_next_string(struct property *prop, const char *cur); -int of_device_is_stdout_path(struct device_node *dn); +bool of_console_check(struct device_node *dn, char *name, int index); #else /* CONFIG_OF */ @@ -564,9 +564,9 @@ static inline int of_machine_is_compatible(const char *compat) return 0; } -static inline int of_device_is_stdout_path(struct device_node *dn) +static inline bool of_console_check(const struct device_node *dn, const char *name, int index) { - return 0; + return false; } static inline const __be32 *of_prop_next_u32(struct property *prop, -- cgit v1.2.3-70-g09d2 From a752ee56ad84bf9a35b8323af1ad22b03c1df2c4 Mon Sep 17 00:00:00 2001 From: Grant Likely Date: Fri, 28 Mar 2014 08:12:18 -0700 Subject: tty: Update hypervisor tty drivers to use core stdout parsing code. The evh_bytechan, hvc_opal and hvc_vio drivers all open code the parsing of the stdout node in the device tree. This patch simplifies the driver by removing the duplicated functionality. Signed-off-by: Grant Likely --- drivers/of/base.c | 5 ++++- drivers/tty/ehv_bytechan.c | 43 ++++--------------------------------------- drivers/tty/hvc/hvc_opal.c | 15 +++------------ drivers/tty/hvc/hvc_vio.c | 29 ++++++++++------------------- include/linux/of.h | 1 + 5 files changed, 22 insertions(+), 71 deletions(-) (limited to 'include/linux/of.h') diff --git a/drivers/of/base.c b/drivers/of/base.c index df9b2bb7bb2..e4f95ba0a3e 100644 --- a/drivers/of/base.c +++ b/drivers/of/base.c @@ -36,7 +36,7 @@ struct device_node *of_allnodes; EXPORT_SYMBOL(of_allnodes); struct device_node *of_chosen; struct device_node *of_aliases; -static struct device_node *of_stdout; +struct device_node *of_stdout; static struct kset *of_kset; @@ -2063,9 +2063,12 @@ void of_alias_scan(void * (*dt_alloc)(u64 size, u64 align)) of_chosen = of_find_node_by_path("/chosen@0"); if (of_chosen) { + /* linux,stdout-path and /aliases/stdout are for legacy compatibility */ const char *name = of_get_property(of_chosen, "stdout-path", NULL); if (!name) name = of_get_property(of_chosen, "linux,stdout-path", NULL); + if (IS_ENABLED(CONFIG_PPC) && !name) + name = of_get_property(of_aliases, "stdout", NULL); if (name) of_stdout = of_find_node_by_path(name); } diff --git a/drivers/tty/ehv_bytechan.c b/drivers/tty/ehv_bytechan.c index 0419b69e270..4f485e88f60 100644 --- a/drivers/tty/ehv_bytechan.c +++ b/drivers/tty/ehv_bytechan.c @@ -108,55 +108,23 @@ static void disable_tx_interrupt(struct ehv_bc_data *bc) * * The byte channel to be used for the console is specified via a "stdout" * property in the /chosen node. - * - * For compatible with legacy device trees, we also look for a "stdout" alias. */ static int find_console_handle(void) { - struct device_node *np, *np2; + struct device_node *np = of_stdout; const char *sprop = NULL; const uint32_t *iprop; - np = of_find_node_by_path("/chosen"); - if (np) - sprop = of_get_property(np, "stdout-path", NULL); - - if (!np || !sprop) { - of_node_put(np); - np = of_find_node_by_name(NULL, "aliases"); - if (np) - sprop = of_get_property(np, "stdout", NULL); - } - - if (!sprop) { - of_node_put(np); - return 0; - } - /* We don't care what the aliased node is actually called. We only * care if it's compatible with "epapr,hv-byte-channel", because that - * indicates that it's a byte channel node. We use a temporary - * variable, 'np2', because we can't release 'np' until we're done with - * 'sprop'. + * indicates that it's a byte channel node. */ - np2 = of_find_node_by_path(sprop); - of_node_put(np); - np = np2; - if (!np) { - pr_warning("ehv-bc: stdout node '%s' does not exist\n", sprop); - return 0; - } - - /* Is it a byte channel? */ - if (!of_device_is_compatible(np, "epapr,hv-byte-channel")) { - of_node_put(np); + if (!np || !of_device_is_compatible(np, "epapr,hv-byte-channel")) return 0; - } stdout_irq = irq_of_parse_and_map(np, 0); if (stdout_irq == NO_IRQ) { - pr_err("ehv-bc: no 'interrupts' property in %s node\n", sprop); - of_node_put(np); + pr_err("ehv-bc: no 'interrupts' property in %s node\n", np->full_name); return 0; } @@ -167,12 +135,9 @@ static int find_console_handle(void) if (!iprop) { pr_err("ehv-bc: no 'hv-handle' property in %s node\n", np->name); - of_node_put(np); return 0; } stdout_bc = be32_to_cpu(*iprop); - - of_node_put(np); return 1; } diff --git a/drivers/tty/hvc/hvc_opal.c b/drivers/tty/hvc/hvc_opal.c index a585079b4b3..a2cc5f834c6 100644 --- a/drivers/tty/hvc/hvc_opal.c +++ b/drivers/tty/hvc/hvc_opal.c @@ -342,22 +342,13 @@ static void udbg_init_opal_common(void) void __init hvc_opal_init_early(void) { - struct device_node *stdout_node = NULL; + struct device_node *stdout_node = of_node_get(of_stdout); const __be32 *termno; - const char *name = NULL; const struct hv_ops *ops; u32 index; - /* find the boot console from /chosen/stdout */ - if (of_chosen) - name = of_get_property(of_chosen, "linux,stdout-path", NULL); - if (name) { - stdout_node = of_find_node_by_path(name); - if (!stdout_node) { - pr_err("hvc_opal: Failed to locate default console!\n"); - return; - } - } else { + /* If the console wasn't in /chosen, try /ibm,opal */ + if (!stdout_node) { struct device_node *opal, *np; /* Current OPAL takeover doesn't provide the stdout diff --git a/drivers/tty/hvc/hvc_vio.c b/drivers/tty/hvc/hvc_vio.c index b594abfbf21..5618b5fc750 100644 --- a/drivers/tty/hvc/hvc_vio.c +++ b/drivers/tty/hvc/hvc_vio.c @@ -404,42 +404,35 @@ module_exit(hvc_vio_exit); void __init hvc_vio_init_early(void) { - struct device_node *stdout_node; const __be32 *termno; const char *name; const struct hv_ops *ops; /* find the boot console from /chosen/stdout */ - if (!of_chosen) + if (!of_stdout) return; - name = of_get_property(of_chosen, "linux,stdout-path", NULL); - if (name == NULL) - return; - stdout_node = of_find_node_by_path(name); - if (!stdout_node) - return; - name = of_get_property(stdout_node, "name", NULL); + name = of_get_property(of_stdout, "name", NULL); if (!name) { printk(KERN_WARNING "stdout node missing 'name' property!\n"); - goto out; + return; } /* Check if it's a virtual terminal */ if (strncmp(name, "vty", 3) != 0) - goto out; - termno = of_get_property(stdout_node, "reg", NULL); + return; + termno = of_get_property(of_stdout, "reg", NULL); if (termno == NULL) - goto out; + return; hvterm_priv0.termno = of_read_number(termno, 1); spin_lock_init(&hvterm_priv0.buf_lock); hvterm_privs[0] = &hvterm_priv0; /* Check the protocol */ - if (of_device_is_compatible(stdout_node, "hvterm1")) { + if (of_device_is_compatible(of_stdout, "hvterm1")) { hvterm_priv0.proto = HV_PROTOCOL_RAW; ops = &hvterm_raw_ops; } - else if (of_device_is_compatible(stdout_node, "hvterm-protocol")) { + else if (of_device_is_compatible(of_stdout, "hvterm-protocol")) { hvterm_priv0.proto = HV_PROTOCOL_HVSI; ops = &hvterm_hvsi_ops; hvsilib_init(&hvterm_priv0.hvsi, hvc_get_chars, hvc_put_chars, @@ -447,7 +440,7 @@ void __init hvc_vio_init_early(void) /* HVSI, perform the handshake now */ hvsilib_establish(&hvterm_priv0.hvsi); } else - goto out; + return; udbg_putc = udbg_hvc_putc; udbg_getc = udbg_hvc_getc; udbg_getc_poll = udbg_hvc_getc_poll; @@ -456,14 +449,12 @@ void __init hvc_vio_init_early(void) * backend for HVSI, only do udbg */ if (hvterm_priv0.proto == HV_PROTOCOL_HVSI) - goto out; + return; #endif /* Check whether the user has requested a different console. */ if (!strstr(cmd_line, "console=")) add_preferred_console("hvc", 0, NULL); hvc_instantiate(0, 0, ops); -out: - of_node_put(stdout_node); } /* call this from early_init() for a working debug console on diff --git a/include/linux/of.h b/include/linux/of.h index 9d9734056e3..f0d256273c8 100644 --- a/include/linux/of.h +++ b/include/linux/of.h @@ -113,6 +113,7 @@ static inline void of_node_put(struct device_node *node) { } extern struct device_node *of_allnodes; extern struct device_node *of_chosen; extern struct device_node *of_aliases; +extern struct device_node *of_stdout; extern raw_spinlock_t devtree_lock; static inline bool of_have_populated_dt(void) -- cgit v1.2.3-70-g09d2 From 75f353b61342b5847c7f6d8499fd6301dce09845 Mon Sep 17 00:00:00 2001 From: Grant Likely Date: Tue, 24 Jun 2014 16:13:47 +0100 Subject: of/platform: Fix of_platform_device_destroy iteration of devices of_platform_destroy does not work properly, since the tree population test was iterating on all devices having as its parent the given platform device. The check was intended to check whether any other platform or amba devices created by of_platform_populate were still populated, but instead checked for every kind of device. This is wrong, since platform devices typically create a subsystem regular device and set themselves as parents. Instead, go ahead and call the unregister functions for any devices created with of_platform_populate. The driver core will take care of unbinding drivers, and drivers are responsible for getting rid of any child devices that weren't created by of_platform_populate. Signed-off-by: Grant Likely Signed-off-by: Pantelis Antoniou --- drivers/of/platform.c | 32 +++++++++----------------------- include/linux/of.h | 1 + include/linux/of_platform.h | 7 ++----- 3 files changed, 12 insertions(+), 28 deletions(-) (limited to 'include/linux/of.h') diff --git a/drivers/of/platform.c b/drivers/of/platform.c index 500436f9be7..0197725e033 100644 --- a/drivers/of/platform.c +++ b/drivers/of/platform.c @@ -422,6 +422,7 @@ static int of_platform_bus_create(struct device_node *bus, break; } } + of_node_set_flag(bus, OF_POPULATED_BUS); return rc; } @@ -508,19 +509,13 @@ EXPORT_SYMBOL_GPL(of_platform_populate); static int of_platform_device_destroy(struct device *dev, void *data) { - bool *children_left = data; - /* Do not touch devices not populated from the device tree */ - if (!dev->of_node || !of_node_check_flag(dev->of_node, OF_POPULATED)) { - *children_left = true; + if (!dev->of_node || !of_node_check_flag(dev->of_node, OF_POPULATED)) return 0; - } - /* Recurse, but don't touch this device if it has any children left */ - if (of_platform_depopulate(dev) != 0) { - *children_left = true; - return 0; - } + /* Recurse for any nodes that were treated as busses */ + if (of_node_check_flag(dev->of_node, OF_POPULATED_BUS)) + device_for_each_child(dev, NULL, of_platform_device_destroy); if (dev->bus == &platform_bus_type) platform_device_unregister(to_platform_device(dev)); @@ -528,19 +523,15 @@ static int of_platform_device_destroy(struct device *dev, void *data) else if (dev->bus == &amba_bustype) amba_device_unregister(to_amba_device(dev)); #endif - else { - *children_left = true; - return 0; - } of_node_clear_flag(dev->of_node, OF_POPULATED); - + of_node_clear_flag(dev->of_node, OF_POPULATED_BUS); return 0; } /** * of_platform_depopulate() - Remove devices populated from device tree - * @parent: device which childred will be removed + * @parent: device which children will be removed * * Complementary to of_platform_populate(), this function removes children * of the given device (and, recurrently, their children) that have been @@ -550,14 +541,9 @@ static int of_platform_device_destroy(struct device *dev, void *data) * Returns 0 when all children devices have been removed or * -EBUSY when some children remained. */ -int of_platform_depopulate(struct device *parent) +void of_platform_depopulate(struct device *parent) { - bool children_left = false; - - device_for_each_child(parent, &children_left, - of_platform_device_destroy); - - return children_left ? -EBUSY : 0; + device_for_each_child(parent, NULL, of_platform_device_destroy); } EXPORT_SYMBOL_GPL(of_platform_depopulate); diff --git a/include/linux/of.h b/include/linux/of.h index 196b34c1ef4..abf829a1f15 100644 --- a/include/linux/of.h +++ b/include/linux/of.h @@ -204,6 +204,7 @@ static inline unsigned long of_read_ulong(const __be32 *cell, int size) #define OF_DYNAMIC 1 /* node and properties were allocated via kmalloc */ #define OF_DETACHED 2 /* node has been detached from the device tree */ #define OF_POPULATED 3 /* device already created for the node */ +#define OF_POPULATED_BUS 4 /* of_platform_populate recursed to children of this node */ #define OF_IS_DYNAMIC(x) test_bit(OF_DYNAMIC, &x->_flags) #define OF_MARK_DYNAMIC(x) set_bit(OF_DYNAMIC, &x->_flags) diff --git a/include/linux/of_platform.h b/include/linux/of_platform.h index d96e1badbee..c2b0627a231 100644 --- a/include/linux/of_platform.h +++ b/include/linux/of_platform.h @@ -72,7 +72,7 @@ extern int of_platform_populate(struct device_node *root, const struct of_device_id *matches, const struct of_dev_auxdata *lookup, struct device *parent); -extern int of_platform_depopulate(struct device *parent); +extern void of_platform_depopulate(struct device *parent); #else static inline int of_platform_populate(struct device_node *root, const struct of_device_id *matches, @@ -81,10 +81,7 @@ static inline int of_platform_populate(struct device_node *root, { return -ENODEV; } -static inline int of_platform_depopulate(struct device *parent) -{ - return -ENODEV; -} +static inline void of_platform_depopulate(struct device *parent) { } #endif #endif /* _LINUX_OF_PLATFORM_H */ -- cgit v1.2.3-70-g09d2 From 8a2b22a2595bf89d4396530edf8388159fad9d83 Mon Sep 17 00:00:00 2001 From: Grant Likely Date: Wed, 23 Jul 2014 17:05:06 -0600 Subject: of: Make devicetree sysfs update functions consistent. All of the DT modification functions are split into two parts, the first part manipulates the DT data structure, and the second part updates sysfs, but the code isn't very consistent about how the second half is called. They don't all enforce the same rules about when it is valid to update sysfs, and there isn't any clarity on locking. The transactional DT modification feature that is coming also needs access to these functions so that it can perform all the structure changes together, and then all the sysfs updates as a second stage instead of doing each one at a time. Fix up the second have by creating a separate __of_*_sysfs() function for each of the helpers. The new functions have consistent naming (ie. of_node_add() becomes __of_attach_node_sysfs()) and all of them now defer if of_init hasn't been called yet. Callers of the new functions must hold the of_mutex to ensure there are no race conditions with of_init(). The mutex ensures that there will only ever be one writer to the tree at any given time. There can still be any number of readers and the raw_spin_lock is still used to make sure access to the data structure is still consistent. Finally, put the function prototypes into of_private.h so they are accessible to the transaction code. Signed-off-by: Pantelis Antoniou [grant.likely: Changed suffix from _post to _sysfs to match existing code] [grant.likely: Reorganized to eliminate trivial wrappers] Signed-off-by: Grant Likely --- drivers/of/base.c | 96 +++++++++++++++++++++++++------------------------ drivers/of/dynamic.c | 12 +++++-- drivers/of/of_private.h | 10 ++++++ include/linux/of.h | 2 -- 4 files changed, 69 insertions(+), 51 deletions(-) (limited to 'include/linux/of.h') diff --git a/drivers/of/base.c b/drivers/of/base.c index b403f9d9846..ad4929cbd87 100644 --- a/drivers/of/base.c +++ b/drivers/of/base.c @@ -37,10 +37,13 @@ struct device_node *of_chosen; struct device_node *of_aliases; static struct device_node *of_stdout; -static struct kset *of_kset; +struct kset *of_kset; /* - * Used to protect the of_aliases, to hold off addition of nodes to sysfs + * Used to protect the of_aliases, to hold off addition of nodes to sysfs. + * This mutex must be held whenever modifications are being made to the + * device tree. The of_{attach,detach}_node() and + * of_{add,remove,update}_property() helpers make sure this happens. */ DEFINE_MUTEX(of_mutex); @@ -127,13 +130,16 @@ static const char *safe_name(struct kobject *kobj, const char *orig_name) return name; } -static int __of_add_property_sysfs(struct device_node *np, struct property *pp) +int __of_add_property_sysfs(struct device_node *np, struct property *pp) { int rc; /* Important: Don't leak passwords */ bool secure = strncmp(pp->name, "security-", 9) == 0; + if (!of_kset || !of_node_is_attached(np)) + return 0; + sysfs_bin_attr_init(&pp->attr); pp->attr.attr.name = safe_name(&np->kobj, pp->name); pp->attr.attr.mode = secure ? S_IRUSR : S_IRUGO; @@ -145,12 +151,15 @@ static int __of_add_property_sysfs(struct device_node *np, struct property *pp) return rc; } -static int __of_node_add(struct device_node *np) +int __of_attach_node_sysfs(struct device_node *np) { const char *name; struct property *pp; int rc; + if (!of_kset) + return 0; + np->kobj.kset = of_kset; if (!np->parent) { /* Nodes without parents are new top level trees */ @@ -172,26 +181,6 @@ static int __of_node_add(struct device_node *np) return 0; } -int of_node_add(struct device_node *np) -{ - int rc = 0; - - BUG_ON(!of_node_is_initialized(np)); - - /* - * Grab the mutex here so that in a race condition between of_init() and - * of_node_add(), node addition will still be consistent. - */ - mutex_lock(&of_mutex); - if (of_kset) - rc = __of_node_add(np); - else - /* This scenario may be perfectly valid, but report it anyway */ - pr_info("of_node_add(%s) before of_init()\n", np->full_name); - mutex_unlock(&of_mutex); - return rc; -} - static int __init of_init(void) { struct device_node *np; @@ -204,7 +193,7 @@ static int __init of_init(void) return -ENOMEM; } for_each_of_allnodes(np) - __of_node_add(np); + __of_attach_node_sysfs(np); mutex_unlock(&of_mutex); /* Symlink in /proc as required by userspace ABI */ @@ -1689,15 +1678,17 @@ int of_add_property(struct device_node *np, struct property *prop) if (rc) return rc; + mutex_lock(&of_mutex); + raw_spin_lock_irqsave(&devtree_lock, flags); rc = __of_add_property(np, prop); raw_spin_unlock_irqrestore(&devtree_lock, flags); - if (rc) - return rc; - if (of_node_is_attached(np)) + if (!rc) __of_add_property_sysfs(np, prop); + mutex_unlock(&of_mutex); + return rc; } @@ -1720,6 +1711,13 @@ int __of_remove_property(struct device_node *np, struct property *prop) return 0; } +void __of_remove_property_sysfs(struct device_node *np, struct property *prop) +{ + /* at early boot, bail here and defer setup to of_init() */ + if (of_kset && of_node_is_attached(np)) + sysfs_remove_bin_file(&np->kobj, &prop->attr); +} + /** * of_remove_property - Remove a property from a node. * @@ -1737,20 +1735,18 @@ int of_remove_property(struct device_node *np, struct property *prop) if (rc) return rc; + mutex_lock(&of_mutex); + raw_spin_lock_irqsave(&devtree_lock, flags); rc = __of_remove_property(np, prop); raw_spin_unlock_irqrestore(&devtree_lock, flags); - if (rc) - return rc; - - /* at early boot, bail hear and defer setup to of_init() */ - if (!of_kset) - return 0; + if (!rc) + __of_remove_property_sysfs(np, prop); - sysfs_remove_bin_file(&np->kobj, &prop->attr); + mutex_unlock(&of_mutex); - return 0; + return rc; } int __of_update_property(struct device_node *np, struct property *newprop, @@ -1779,6 +1775,18 @@ int __of_update_property(struct device_node *np, struct property *newprop, return 0; } +void __of_update_property_sysfs(struct device_node *np, struct property *newprop, + struct property *oldprop) +{ + /* At early boot, bail out and defer setup to of_init() */ + if (!of_kset) + return; + + if (oldprop) + sysfs_remove_bin_file(&np->kobj, &oldprop->attr); + __of_add_property_sysfs(np, newprop); +} + /* * of_update_property - Update a property in a node, if the property does * not exist, add it. @@ -1801,22 +1809,18 @@ int of_update_property(struct device_node *np, struct property *newprop) if (rc) return rc; + mutex_lock(&of_mutex); + raw_spin_lock_irqsave(&devtree_lock, flags); rc = __of_update_property(np, newprop, &oldprop); raw_spin_unlock_irqrestore(&devtree_lock, flags); - if (rc) - return rc; - /* At early boot, bail out and defer setup to of_init() */ - if (!of_kset) - return 0; + if (!rc) + __of_update_property_sysfs(np, newprop, oldprop); - /* Update the sysfs attribute */ - if (oldprop) - sysfs_remove_bin_file(&np->kobj, &oldprop->attr); - __of_add_property_sysfs(np, newprop); + mutex_unlock(&of_mutex); - return 0; + return rc; } static void of_alias_add(struct alias_prop *ap, struct device_node *np, diff --git a/drivers/of/dynamic.c b/drivers/of/dynamic.c index 75fcc66fcef..c875787fa39 100644 --- a/drivers/of/dynamic.c +++ b/drivers/of/dynamic.c @@ -41,11 +41,13 @@ void of_node_put(struct device_node *node) } EXPORT_SYMBOL(of_node_put); -static void of_node_remove(struct device_node *np) +void __of_detach_node_sysfs(struct device_node *np) { struct property *pp; BUG_ON(!of_node_is_initialized(np)); + if (!of_kset) + return; /* only remove properties if on sysfs */ if (of_node_is_attached(np)) { @@ -115,11 +117,13 @@ int of_attach_node(struct device_node *np) if (rc) return rc; + mutex_lock(&of_mutex); raw_spin_lock_irqsave(&devtree_lock, flags); __of_attach_node(np); raw_spin_unlock_irqrestore(&devtree_lock, flags); - of_node_add(np); + __of_attach_node_sysfs(np); + mutex_unlock(&of_mutex); return 0; } @@ -174,11 +178,13 @@ int of_detach_node(struct device_node *np) if (rc) return rc; + mutex_lock(&of_mutex); raw_spin_lock_irqsave(&devtree_lock, flags); __of_detach_node(np); raw_spin_unlock_irqrestore(&devtree_lock, flags); - of_node_remove(np); + __of_detach_node_sysfs(np); + mutex_unlock(&of_mutex); return rc; } diff --git a/drivers/of/of_private.h b/drivers/of/of_private.h index 0f6089722af..0d99ba8caee 100644 --- a/drivers/of/of_private.h +++ b/drivers/of/of_private.h @@ -33,6 +33,8 @@ struct alias_prop { extern struct mutex of_mutex; extern struct list_head aliases_lookup; +extern struct kset *of_kset; + static inline struct device_node *kobj_to_device_node(struct kobject *kobj) { @@ -62,11 +64,19 @@ struct property *__of_prop_dup(const struct property *prop, gfp_t allocflags); struct device_node *__of_node_alloc(const char *full_name, gfp_t allocflags); extern int __of_add_property(struct device_node *np, struct property *prop); +extern int __of_add_property_sysfs(struct device_node *np, + struct property *prop); extern int __of_remove_property(struct device_node *np, struct property *prop); +extern void __of_remove_property_sysfs(struct device_node *np, + struct property *prop); extern int __of_update_property(struct device_node *np, struct property *newprop, struct property **oldprop); +extern void __of_update_property_sysfs(struct device_node *np, + struct property *newprop, struct property *oldprop); extern void __of_attach_node(struct device_node *np); +extern int __of_attach_node_sysfs(struct device_node *np); extern void __of_detach_node(struct device_node *np); +extern void __of_detach_node_sysfs(struct device_node *np); #endif /* _LINUX_OF_PRIVATE_H */ diff --git a/include/linux/of.h b/include/linux/of.h index abf829a1f15..705fa12fca7 100644 --- a/include/linux/of.h +++ b/include/linux/of.h @@ -74,8 +74,6 @@ struct of_phandle_args { uint32_t args[MAX_PHANDLE_ARGS]; }; -extern int of_node_add(struct device_node *node); - /* initialize a node */ extern struct kobj_type of_node_ktype; static inline void of_node_init(struct device_node *node) -- cgit v1.2.3-70-g09d2 From 259092a35c7e11f1d4616b0f5b3ba7b851fe4fa6 Mon Sep 17 00:00:00 2001 From: Grant Likely Date: Wed, 16 Jul 2014 12:48:23 -0600 Subject: of: Reorder device tree changes and notifiers Currently, devicetree reconfig notifiers get emitted before the change is applied to the tree, but that behaviour is problematic if the receiver wants the determine the new state of the tree. The current users don't care, but the changeset code to follow will be making multiple changes at once. Reorder notifiers to get emitted after the change has been applied to the tree so that callbacks see the new tree state. At the same time, fixup the existing callbacks to expect the new order. There are a few callbacks that compare the old and new values of a changed property. Put both property pointers into the of_prop_reconfig structure. The current notifiers also allow the notifier callback to fail and cancel the change to the tree, but that feature isn't actually used. It really isn't valid to ignore a tree modification provided by firmware anyway, so remove the ability to cancel a change to the tree. Signed-off-by: Grant Likely Cc: Nathan Fontenot --- arch/powerpc/platforms/pseries/hotplug-memory.c | 2 +- drivers/crypto/nx/nx-842.c | 30 +++++++------------------ drivers/of/base.c | 21 ++++++++--------- drivers/of/dynamic.c | 18 +++++++-------- drivers/of/of_private.h | 4 ++-- include/linux/of.h | 1 + 6 files changed, 29 insertions(+), 47 deletions(-) (limited to 'include/linux/of.h') diff --git a/arch/powerpc/platforms/pseries/hotplug-memory.c b/arch/powerpc/platforms/pseries/hotplug-memory.c index 7995135170a..ac01e188fae 100644 --- a/arch/powerpc/platforms/pseries/hotplug-memory.c +++ b/arch/powerpc/platforms/pseries/hotplug-memory.c @@ -194,7 +194,7 @@ static int pseries_update_drconf_memory(struct of_prop_reconfig *pr) if (!memblock_size) return -EINVAL; - p = (u32 *)of_get_property(pr->dn, "ibm,dynamic-memory", NULL); + p = (u32 *) pr->old_prop->value; if (!p) return -EINVAL; diff --git a/drivers/crypto/nx/nx-842.c b/drivers/crypto/nx/nx-842.c index 502edf0a293..c897c3a5ee1 100644 --- a/drivers/crypto/nx/nx-842.c +++ b/drivers/crypto/nx/nx-842.c @@ -936,28 +936,14 @@ static int nx842_OF_upd(struct property *new_prop) goto error_out; } - /* Set ptr to new property if provided */ - if (new_prop) { - /* Single property */ - if (!strncmp(new_prop->name, "status", new_prop->length)) { - status = new_prop; - - } else if (!strncmp(new_prop->name, "ibm,max-sg-len", - new_prop->length)) { - maxsglen = new_prop; - - } else if (!strncmp(new_prop->name, "ibm,max-sync-cop", - new_prop->length)) { - maxsyncop = new_prop; - - } else { - /* - * Skip the update, the property being updated - * has no impact. - */ - goto out; - } - } + /* + * If this is a property update, there are only certain properties that + * we care about. Bail if it isn't in the below list + */ + if (new_prop && (strncmp(new_prop->name, "status", new_prop->length) || + strncmp(new_prop->name, "ibm,max-sg-len", new_prop->length) || + strncmp(new_prop->name, "ibm,max-sync-cop", new_prop->length))) + goto out; /* Perform property updates */ ret = nx842_OF_upd_status(new_devdata, status); diff --git a/drivers/of/base.c b/drivers/of/base.c index ededf8e3314..a7ad1013edf 100644 --- a/drivers/of/base.c +++ b/drivers/of/base.c @@ -1674,10 +1674,6 @@ int of_add_property(struct device_node *np, struct property *prop) unsigned long flags; int rc; - rc = of_property_notify(OF_RECONFIG_ADD_PROPERTY, np, prop); - if (rc) - return rc; - mutex_lock(&of_mutex); raw_spin_lock_irqsave(&devtree_lock, flags); @@ -1689,6 +1685,9 @@ int of_add_property(struct device_node *np, struct property *prop) mutex_unlock(&of_mutex); + if (!rc) + of_property_notify(OF_RECONFIG_ADD_PROPERTY, np, prop, NULL); + return rc; } @@ -1731,10 +1730,6 @@ int of_remove_property(struct device_node *np, struct property *prop) unsigned long flags; int rc; - rc = of_property_notify(OF_RECONFIG_REMOVE_PROPERTY, np, prop); - if (rc) - return rc; - mutex_lock(&of_mutex); raw_spin_lock_irqsave(&devtree_lock, flags); @@ -1746,6 +1741,9 @@ int of_remove_property(struct device_node *np, struct property *prop) mutex_unlock(&of_mutex); + if (!rc) + of_property_notify(OF_RECONFIG_REMOVE_PROPERTY, np, prop, NULL); + return rc; } @@ -1805,10 +1803,6 @@ int of_update_property(struct device_node *np, struct property *newprop) if (!newprop->name) return -EINVAL; - rc = of_property_notify(OF_RECONFIG_UPDATE_PROPERTY, np, newprop); - if (rc) - return rc; - mutex_lock(&of_mutex); raw_spin_lock_irqsave(&devtree_lock, flags); @@ -1820,6 +1814,9 @@ int of_update_property(struct device_node *np, struct property *newprop) mutex_unlock(&of_mutex); + if (!rc) + of_property_notify(OF_RECONFIG_UPDATE_PROPERTY, np, newprop, oldprop); + return rc; } diff --git a/drivers/of/dynamic.c b/drivers/of/dynamic.c index 7c020b9a331..7bd5501736a 100644 --- a/drivers/of/dynamic.c +++ b/drivers/of/dynamic.c @@ -83,7 +83,7 @@ int of_reconfig_notify(unsigned long action, void *p) } int of_property_notify(int action, struct device_node *np, - struct property *prop) + struct property *prop, struct property *oldprop) { struct of_prop_reconfig pr; @@ -93,6 +93,7 @@ int of_property_notify(int action, struct device_node *np, pr.dn = np; pr.prop = prop; + pr.old_prop = oldprop; return of_reconfig_notify(action, &pr); } @@ -125,11 +126,6 @@ void __of_attach_node(struct device_node *np) int of_attach_node(struct device_node *np) { unsigned long flags; - int rc; - - rc = of_reconfig_notify(OF_RECONFIG_ATTACH_NODE, np); - if (rc) - return rc; mutex_lock(&of_mutex); raw_spin_lock_irqsave(&devtree_lock, flags); @@ -138,6 +134,9 @@ int of_attach_node(struct device_node *np) __of_attach_node_sysfs(np); mutex_unlock(&of_mutex); + + of_reconfig_notify(OF_RECONFIG_ATTACH_NODE, np); + return 0; } @@ -188,10 +187,6 @@ int of_detach_node(struct device_node *np) unsigned long flags; int rc = 0; - rc = of_reconfig_notify(OF_RECONFIG_DETACH_NODE, np); - if (rc) - return rc; - mutex_lock(&of_mutex); raw_spin_lock_irqsave(&devtree_lock, flags); __of_detach_node(np); @@ -199,6 +194,9 @@ int of_detach_node(struct device_node *np) __of_detach_node_sysfs(np); mutex_unlock(&of_mutex); + + of_reconfig_notify(OF_RECONFIG_DETACH_NODE, np); + return rc; } diff --git a/drivers/of/of_private.h b/drivers/of/of_private.h index 8129c0e58d7..f69ccb1fa30 100644 --- a/drivers/of/of_private.h +++ b/drivers/of/of_private.h @@ -43,11 +43,11 @@ static inline struct device_node *kobj_to_device_node(struct kobject *kobj) #if defined(CONFIG_OF_DYNAMIC) extern int of_property_notify(int action, struct device_node *np, - struct property *prop); + struct property *prop, struct property *old_prop); extern void of_node_release(struct kobject *kobj); #else /* CONFIG_OF_DYNAMIC */ static inline int of_property_notify(int action, struct device_node *np, - struct property *prop) + struct property *prop, struct property *old_prop) { return 0; } diff --git a/include/linux/of.h b/include/linux/of.h index 705fa12fca7..400f18cb4ff 100644 --- a/include/linux/of.h +++ b/include/linux/of.h @@ -321,6 +321,7 @@ extern int of_update_property(struct device_node *np, struct property *newprop); struct of_prop_reconfig { struct device_node *dn; struct property *prop; + struct property *old_prop; }; extern int of_reconfig_notifier_register(struct notifier_block *); -- cgit v1.2.3-70-g09d2 From 201c910bd6898d81d4ac6685d0f421b7e10f3c5d Mon Sep 17 00:00:00 2001 From: Pantelis Antoniou Date: Fri, 4 Jul 2014 19:58:49 +0300 Subject: of: Transactional DT support. Introducing DT transactional support. A DT transaction is a method which allows one to apply changes in the live tree, in such a way that either the full set of changes take effect, or the state of the tree can be rolled-back to the state it was before it was attempted. An applied transaction can be rolled-back at any time. Documentation is in Documentation/devicetree/changesets.txt Signed-off-by: Pantelis Antoniou [glikely: Removed device notifiers and reworked to be more consistent] Signed-off-by: Grant Likely --- Documentation/devicetree/changesets.txt | 40 ++++ drivers/of/dynamic.c | 344 ++++++++++++++++++++++++++++++++ drivers/of/of_private.h | 9 + drivers/of/selftest.c | 51 +++++ drivers/of/testcase-data/testcases.dtsi | 10 + include/linux/of.h | 76 +++++++ 6 files changed, 530 insertions(+) create mode 100644 Documentation/devicetree/changesets.txt (limited to 'include/linux/of.h') diff --git a/Documentation/devicetree/changesets.txt b/Documentation/devicetree/changesets.txt new file mode 100644 index 00000000000..935ba5acc34 --- /dev/null +++ b/Documentation/devicetree/changesets.txt @@ -0,0 +1,40 @@ +A DT changeset is a method which allows one to apply changes +in the live tree in such a way that either the full set of changes +will be applied, or none of them will be. If an error occurs partway +through applying the changeset, then the tree will be rolled back to the +previous state. A changeset can also be removed after it has been +applied. + +When a changeset is applied, all of the changes get applied to the tree +at once before emitting OF_RECONFIG notifiers. This is so that the +receiver sees a complete and consistent state of the tree when it +receives the notifier. + +The sequence of a changeset is as follows. + +1. of_changeset_init() - initializes a changeset + +2. A number of DT tree change calls, of_changeset_attach_node(), +of_changeset_detach_node(), of_changeset_add_property(), +of_changeset_remove_property, of_changeset_update_property() to prepare +a set of changes. No changes to the active tree are made at this point. +All the change operations are recorded in the of_changeset 'entries' +list. + +3. mutex_lock(of_mutex) - starts a changeset; The global of_mutex +ensures there can only be one editor at a time. + +4. of_changeset_apply() - Apply the changes to the tree. Either the +entire changeset will get applied, or if there is an error the tree will +be restored to the previous state + +5. mutex_unlock(of_mutex) - All operations complete, release the mutex + +If a successfully applied changeset needs to be removed, it can be done +with the following sequence. + +1. mutex_lock(of_mutex) + +2. of_changeset_revert() + +3. mutex_unlock(of_mutex) diff --git a/drivers/of/dynamic.c b/drivers/of/dynamic.c index 7bd5501736a..c1002b7be78 100644 --- a/drivers/of/dynamic.c +++ b/drivers/of/dynamic.c @@ -314,3 +314,347 @@ struct device_node *__of_node_alloc(const char *full_name, gfp_t allocflags) kfree(node); return NULL; } + +static void __of_changeset_entry_destroy(struct of_changeset_entry *ce) +{ + of_node_put(ce->np); + list_del(&ce->node); + kfree(ce); +} + +#ifdef DEBUG +static void __of_changeset_entry_dump(struct of_changeset_entry *ce) +{ + switch (ce->action) { + case OF_RECONFIG_ADD_PROPERTY: + pr_debug("%p: %s %s/%s\n", + ce, "ADD_PROPERTY ", ce->np->full_name, + ce->prop->name); + break; + case OF_RECONFIG_REMOVE_PROPERTY: + pr_debug("%p: %s %s/%s\n", + ce, "REMOVE_PROPERTY", ce->np->full_name, + ce->prop->name); + break; + case OF_RECONFIG_UPDATE_PROPERTY: + pr_debug("%p: %s %s/%s\n", + ce, "UPDATE_PROPERTY", ce->np->full_name, + ce->prop->name); + break; + case OF_RECONFIG_ATTACH_NODE: + pr_debug("%p: %s %s\n", + ce, "ATTACH_NODE ", ce->np->full_name); + break; + case OF_RECONFIG_DETACH_NODE: + pr_debug("%p: %s %s\n", + ce, "DETACH_NODE ", ce->np->full_name); + break; + } +} +#else +static inline void __of_changeset_entry_dump(struct of_changeset_entry *ce) +{ + /* empty */ +} +#endif + +static void __of_changeset_entry_invert(struct of_changeset_entry *ce, + struct of_changeset_entry *rce) +{ + memcpy(rce, ce, sizeof(*rce)); + + switch (ce->action) { + case OF_RECONFIG_ATTACH_NODE: + rce->action = OF_RECONFIG_DETACH_NODE; + break; + case OF_RECONFIG_DETACH_NODE: + rce->action = OF_RECONFIG_ATTACH_NODE; + break; + case OF_RECONFIG_ADD_PROPERTY: + rce->action = OF_RECONFIG_REMOVE_PROPERTY; + break; + case OF_RECONFIG_REMOVE_PROPERTY: + rce->action = OF_RECONFIG_ADD_PROPERTY; + break; + case OF_RECONFIG_UPDATE_PROPERTY: + rce->old_prop = ce->prop; + rce->prop = ce->old_prop; + break; + } +} + +static void __of_changeset_entry_notify(struct of_changeset_entry *ce, bool revert) +{ + struct of_changeset_entry ce_inverted; + int ret; + + if (revert) { + __of_changeset_entry_invert(ce, &ce_inverted); + ce = &ce_inverted; + } + + switch (ce->action) { + case OF_RECONFIG_ATTACH_NODE: + case OF_RECONFIG_DETACH_NODE: + ret = of_reconfig_notify(ce->action, ce->np); + break; + case OF_RECONFIG_ADD_PROPERTY: + case OF_RECONFIG_REMOVE_PROPERTY: + case OF_RECONFIG_UPDATE_PROPERTY: + ret = of_property_notify(ce->action, ce->np, ce->prop, ce->old_prop); + break; + default: + pr_err("%s: invalid devicetree changeset action: %i\n", __func__, + (int)ce->action); + return; + } + + if (ret) + pr_err("%s: notifier error @%s\n", __func__, ce->np->full_name); +} + +static int __of_changeset_entry_apply(struct of_changeset_entry *ce) +{ + struct property *old_prop, **propp; + unsigned long flags; + int ret = 0; + + __of_changeset_entry_dump(ce); + + raw_spin_lock_irqsave(&devtree_lock, flags); + switch (ce->action) { + case OF_RECONFIG_ATTACH_NODE: + __of_attach_node(ce->np); + break; + case OF_RECONFIG_DETACH_NODE: + __of_detach_node(ce->np); + break; + case OF_RECONFIG_ADD_PROPERTY: + /* If the property is in deadprops then it must be removed */ + for (propp = &ce->np->deadprops; *propp; propp = &(*propp)->next) { + if (*propp == ce->prop) { + *propp = ce->prop->next; + ce->prop->next = NULL; + break; + } + } + + ret = __of_add_property(ce->np, ce->prop); + if (ret) { + pr_err("%s: add_property failed @%s/%s\n", + __func__, ce->np->full_name, + ce->prop->name); + break; + } + break; + case OF_RECONFIG_REMOVE_PROPERTY: + ret = __of_remove_property(ce->np, ce->prop); + if (ret) { + pr_err("%s: remove_property failed @%s/%s\n", + __func__, ce->np->full_name, + ce->prop->name); + break; + } + break; + + case OF_RECONFIG_UPDATE_PROPERTY: + /* If the property is in deadprops then it must be removed */ + for (propp = &ce->np->deadprops; *propp; propp = &(*propp)->next) { + if (*propp == ce->prop) { + *propp = ce->prop->next; + ce->prop->next = NULL; + break; + } + } + + ret = __of_update_property(ce->np, ce->prop, &old_prop); + if (ret) { + pr_err("%s: update_property failed @%s/%s\n", + __func__, ce->np->full_name, + ce->prop->name); + break; + } + break; + default: + ret = -EINVAL; + } + raw_spin_unlock_irqrestore(&devtree_lock, flags); + + if (ret) + return ret; + + switch (ce->action) { + case OF_RECONFIG_ATTACH_NODE: + __of_attach_node_sysfs(ce->np); + break; + case OF_RECONFIG_DETACH_NODE: + __of_detach_node_sysfs(ce->np); + break; + case OF_RECONFIG_ADD_PROPERTY: + /* ignore duplicate names */ + __of_add_property_sysfs(ce->np, ce->prop); + break; + case OF_RECONFIG_REMOVE_PROPERTY: + __of_remove_property_sysfs(ce->np, ce->prop); + break; + case OF_RECONFIG_UPDATE_PROPERTY: + __of_update_property_sysfs(ce->np, ce->prop, ce->old_prop); + break; + } + + return 0; +} + +static inline int __of_changeset_entry_revert(struct of_changeset_entry *ce) +{ + struct of_changeset_entry ce_inverted; + + __of_changeset_entry_invert(ce, &ce_inverted); + return __of_changeset_entry_apply(&ce_inverted); +} + +/** + * of_changeset_init - Initialize a changeset for use + * + * @ocs: changeset pointer + * + * Initialize a changeset structure + */ +void of_changeset_init(struct of_changeset *ocs) +{ + memset(ocs, 0, sizeof(*ocs)); + INIT_LIST_HEAD(&ocs->entries); +} + +/** + * of_changeset_destroy - Destroy a changeset + * + * @ocs: changeset pointer + * + * Destroys a changeset. Note that if a changeset is applied, + * its changes to the tree cannot be reverted. + */ +void of_changeset_destroy(struct of_changeset *ocs) +{ + struct of_changeset_entry *ce, *cen; + + list_for_each_entry_safe_reverse(ce, cen, &ocs->entries, node) + __of_changeset_entry_destroy(ce); +} + +/** + * of_changeset_apply - Applies a changeset + * + * @ocs: changeset pointer + * + * Applies a changeset to the live tree. + * Any side-effects of live tree state changes are applied here on + * sucess, like creation/destruction of devices and side-effects + * like creation of sysfs properties and directories. + * Returns 0 on success, a negative error value in case of an error. + * On error the partially applied effects are reverted. + */ +int of_changeset_apply(struct of_changeset *ocs) +{ + struct of_changeset_entry *ce; + int ret; + + /* perform the rest of the work */ + pr_debug("of_changeset: applying...\n"); + list_for_each_entry(ce, &ocs->entries, node) { + ret = __of_changeset_entry_apply(ce); + if (ret) { + pr_err("%s: Error applying changeset (%d)\n", __func__, ret); + list_for_each_entry_continue_reverse(ce, &ocs->entries, node) + __of_changeset_entry_revert(ce); + return ret; + } + } + pr_debug("of_changeset: applied, emitting notifiers.\n"); + + /* drop the global lock while emitting notifiers */ + mutex_unlock(&of_mutex); + list_for_each_entry(ce, &ocs->entries, node) + __of_changeset_entry_notify(ce, 0); + mutex_lock(&of_mutex); + pr_debug("of_changeset: notifiers sent.\n"); + + return 0; +} + +/** + * of_changeset_revert - Reverts an applied changeset + * + * @ocs: changeset pointer + * + * Reverts a changeset returning the state of the tree to what it + * was before the application. + * Any side-effects like creation/destruction of devices and + * removal of sysfs properties and directories are applied. + * Returns 0 on success, a negative error value in case of an error. + */ +int of_changeset_revert(struct of_changeset *ocs) +{ + struct of_changeset_entry *ce; + int ret; + + pr_debug("of_changeset: reverting...\n"); + list_for_each_entry_reverse(ce, &ocs->entries, node) { + ret = __of_changeset_entry_revert(ce); + if (ret) { + pr_err("%s: Error reverting changeset (%d)\n", __func__, ret); + list_for_each_entry_continue(ce, &ocs->entries, node) + __of_changeset_entry_apply(ce); + return ret; + } + } + pr_debug("of_changeset: reverted, emitting notifiers.\n"); + + /* drop the global lock while emitting notifiers */ + mutex_unlock(&of_mutex); + list_for_each_entry_reverse(ce, &ocs->entries, node) + __of_changeset_entry_notify(ce, 1); + mutex_lock(&of_mutex); + pr_debug("of_changeset: notifiers sent.\n"); + + return 0; +} + +/** + * of_changeset_action - Perform a changeset action + * + * @ocs: changeset pointer + * @action: action to perform + * @np: Pointer to device node + * @prop: Pointer to property + * + * On action being one of: + * + OF_RECONFIG_ATTACH_NODE + * + OF_RECONFIG_DETACH_NODE, + * + OF_RECONFIG_ADD_PROPERTY + * + OF_RECONFIG_REMOVE_PROPERTY, + * + OF_RECONFIG_UPDATE_PROPERTY + * Returns 0 on success, a negative error value in case of an error. + */ +int of_changeset_action(struct of_changeset *ocs, unsigned long action, + struct device_node *np, struct property *prop) +{ + struct of_changeset_entry *ce; + + ce = kzalloc(sizeof(*ce), GFP_KERNEL); + if (!ce) { + pr_err("%s: Failed to allocate\n", __func__); + return -ENOMEM; + } + /* get a reference to the node */ + ce->action = action; + ce->np = of_node_get(np); + ce->prop = prop; + + if (action == OF_RECONFIG_UPDATE_PROPERTY && prop) + ce->old_prop = of_find_property(np, prop->name, NULL); + + /* add it to the list */ + list_add_tail(&ce->node, &ocs->entries); + return 0; +} diff --git a/drivers/of/of_private.h b/drivers/of/of_private.h index f69ccb1fa30..858e0a5d9a1 100644 --- a/drivers/of/of_private.h +++ b/drivers/of/of_private.h @@ -81,4 +81,13 @@ extern int __of_attach_node_sysfs(struct device_node *np); extern void __of_detach_node(struct device_node *np); extern void __of_detach_node_sysfs(struct device_node *np); +/* iterators for transactions, used for overlays */ +/* forward iterator */ +#define for_each_transaction_entry(_oft, _te) \ + list_for_each_entry(_te, &(_oft)->te_list, node) + +/* reverse iterator */ +#define for_each_transaction_entry_reverse(_oft, _te) \ + list_for_each_entry_reverse(_te, &(_oft)->te_list, node) + #endif /* _LINUX_OF_PRIVATE_H */ diff --git a/drivers/of/selftest.c b/drivers/of/selftest.c index ee2166f0f36..04e39a183e5 100644 --- a/drivers/of/selftest.c +++ b/drivers/of/selftest.c @@ -293,6 +293,56 @@ static void __init of_selftest_property_copy(void) #endif } +static void __init of_selftest_changeset(void) +{ +#ifdef CONFIG_OF_DYNAMIC + struct property *ppadd, padd = { .name = "prop-add", .length = 0, .value = "" }; + struct property *ppupdate, pupdate = { .name = "prop-update", .length = 5, .value = "abcd" }; + struct property *ppremove; + struct device_node *n1, *n2, *n21, *nremove, *parent; + struct of_changeset chgset; + + of_changeset_init(&chgset); + n1 = __of_node_alloc("/testcase-data/changeset/n1", GFP_KERNEL); + selftest(n1, "testcase setup failure\n"); + n2 = __of_node_alloc("/testcase-data/changeset/n2", GFP_KERNEL); + selftest(n2, "testcase setup failure\n"); + n21 = __of_node_alloc("/testcase-data/changeset/n2/n21", GFP_KERNEL); + selftest(n21, "testcase setup failure %p\n", n21); + nremove = of_find_node_by_path("/testcase-data/changeset/node-remove"); + selftest(nremove, "testcase setup failure\n"); + ppadd = __of_prop_dup(&padd, GFP_KERNEL); + selftest(ppadd, "testcase setup failure\n"); + ppupdate = __of_prop_dup(&pupdate, GFP_KERNEL); + selftest(ppupdate, "testcase setup failure\n"); + parent = nremove->parent; + n1->parent = parent; + n2->parent = parent; + n21->parent = n2; + n2->child = n21; + ppremove = of_find_property(parent, "prop-remove", NULL); + selftest(ppremove, "failed to find removal prop"); + + of_changeset_init(&chgset); + selftest(!of_changeset_attach_node(&chgset, n1), "fail attach n1\n"); + selftest(!of_changeset_attach_node(&chgset, n2), "fail attach n2\n"); + selftest(!of_changeset_detach_node(&chgset, nremove), "fail remove node\n"); + selftest(!of_changeset_attach_node(&chgset, n21), "fail attach n21\n"); + selftest(!of_changeset_add_property(&chgset, parent, ppadd), "fail add prop\n"); + selftest(!of_changeset_update_property(&chgset, parent, ppupdate), "fail update prop\n"); + selftest(!of_changeset_remove_property(&chgset, parent, ppremove), "fail remove prop\n"); + mutex_lock(&of_mutex); + selftest(!of_changeset_apply(&chgset), "apply failed\n"); + mutex_unlock(&of_mutex); + + mutex_lock(&of_mutex); + selftest(!of_changeset_revert(&chgset), "revert failed\n"); + mutex_unlock(&of_mutex); + + of_changeset_destroy(&chgset); +#endif +} + static void __init of_selftest_parse_interrupts(void) { struct device_node *np; @@ -561,6 +611,7 @@ static int __init of_selftest(void) of_selftest_parse_phandle_with_args(); of_selftest_property_match_string(); of_selftest_property_copy(); + of_selftest_changeset(); of_selftest_parse_interrupts(); of_selftest_parse_interrupts_extended(); of_selftest_match_node(); diff --git a/drivers/of/testcase-data/testcases.dtsi b/drivers/of/testcase-data/testcases.dtsi index 6d8d980ac85..669bb07df14 100644 --- a/drivers/of/testcase-data/testcases.dtsi +++ b/drivers/of/testcase-data/testcases.dtsi @@ -1,3 +1,13 @@ +/ { + testcase-data { + changeset { + prop-update = "hello"; + prop-remove = "world"; + node-remove { + }; + }; + }; +}; #include "tests-phandle.dtsi" #include "tests-interrupts.dtsi" #include "tests-match.dtsi" diff --git a/include/linux/of.h b/include/linux/of.h index 400f18cb4ff..bc91fbb13ce 100644 --- a/include/linux/of.h +++ b/include/linux/of.h @@ -786,4 +786,80 @@ typedef void (*of_init_fn_1)(struct device_node *); #define OF_DECLARE_2(table, name, compat, fn) \ _OF_DECLARE(table, name, compat, fn, of_init_fn_2) +/** + * struct of_changeset_entry - Holds a changeset entry + * + * @node: list_head for the log list + * @action: notifier action + * @np: pointer to the device node affected + * @prop: pointer to the property affected + * @old_prop: hold a pointer to the original property + * + * Every modification of the device tree during a changeset + * is held in a list of of_changeset_entry structures. + * That way we can recover from a partial application, or we can + * revert the changeset + */ +struct of_changeset_entry { + struct list_head node; + unsigned long action; + struct device_node *np; + struct property *prop; + struct property *old_prop; +}; + +/** + * struct of_changeset - changeset tracker structure + * + * @entries: list_head for the changeset entries + * + * changesets are a convenient way to apply bulk changes to the + * live tree. In case of an error, changes are rolled-back. + * changesets live on after initial application, and if not + * destroyed after use, they can be reverted in one single call. + */ +struct of_changeset { + struct list_head entries; +}; + +#ifdef CONFIG_OF_DYNAMIC +extern void of_changeset_init(struct of_changeset *ocs); +extern void of_changeset_destroy(struct of_changeset *ocs); +extern int of_changeset_apply(struct of_changeset *ocs); +extern int of_changeset_revert(struct of_changeset *ocs); +extern int of_changeset_action(struct of_changeset *ocs, + unsigned long action, struct device_node *np, + struct property *prop); + +static inline int of_changeset_attach_node(struct of_changeset *ocs, + struct device_node *np) +{ + return of_changeset_action(ocs, OF_RECONFIG_ATTACH_NODE, np, NULL); +} + +static inline int of_changeset_detach_node(struct of_changeset *ocs, + struct device_node *np) +{ + return of_changeset_action(ocs, OF_RECONFIG_DETACH_NODE, np, NULL); +} + +static inline int of_changeset_add_property(struct of_changeset *ocs, + struct device_node *np, struct property *prop) +{ + return of_changeset_action(ocs, OF_RECONFIG_ADD_PROPERTY, np, prop); +} + +static inline int of_changeset_remove_property(struct of_changeset *ocs, + struct device_node *np, struct property *prop) +{ + return of_changeset_action(ocs, OF_RECONFIG_REMOVE_PROPERTY, np, prop); +} + +static inline int of_changeset_update_property(struct of_changeset *ocs, + struct device_node *np, struct property *prop) +{ + return of_changeset_action(ocs, OF_RECONFIG_UPDATE_PROPERTY, np, prop); +} +#endif + #endif /* _LINUX_OF_H */ -- cgit v1.2.3-70-g09d2 From 7941b27b16e3282f6ec8817e36492f1deec753a7 Mon Sep 17 00:00:00 2001 From: Pantelis Antoniou Date: Fri, 4 Jul 2014 19:59:20 +0300 Subject: of: Introduce Device Tree resolve support. Introduce support for dynamic device tree resolution. Using it, it is possible to prepare a device tree that's been loaded on runtime to be modified and inserted at the kernel live tree. Export of of_resolve and bug fix of double free by Guenter Roeck Signed-off-by: Pantelis Antoniou [grant.likely: Don't need to select CONFIG_OF_DYNAMIC and CONFIG_OF_DEVICE] [grant.likely: Don't need to depend on OF or !SPARC] [grant.likely: Factor out duplicate code blocks into single function] Signed-off-by: Grant Likely --- .../devicetree/dynamic-resolution-notes.txt | 25 ++ drivers/of/Kconfig | 3 + drivers/of/Makefile | 1 + drivers/of/resolver.c | 336 +++++++++++++++++++++ include/linux/of.h | 3 + 5 files changed, 368 insertions(+) create mode 100644 Documentation/devicetree/dynamic-resolution-notes.txt create mode 100644 drivers/of/resolver.c (limited to 'include/linux/of.h') diff --git a/Documentation/devicetree/dynamic-resolution-notes.txt b/Documentation/devicetree/dynamic-resolution-notes.txt new file mode 100644 index 00000000000..083d23262ab --- /dev/null +++ b/Documentation/devicetree/dynamic-resolution-notes.txt @@ -0,0 +1,25 @@ +Device Tree Dynamic Resolver Notes +---------------------------------- + +This document describes the implementation of the in-kernel +Device Tree resolver, residing in drivers/of/resolver.c and is a +companion document to Documentation/devicetree/dt-object-internal.txt[1] + +How the resolver works +---------------------- + +The resolver is given as an input an arbitrary tree compiled with the +proper dtc option and having a /plugin/ tag. This generates the +appropriate __fixups__ & __local_fixups__ nodes as described in [1]. + +In sequence the resolver works by the following steps: + +1. Get the maximum device tree phandle value from the live tree + 1. +2. Adjust all the local phandles of the tree to resolve by that amount. +3. Using the __local__fixups__ node information adjust all local references + by the same amount. +4. For each property in the __fixups__ node locate the node it references + in the live tree. This is the label used to tag the node. +5. Retrieve the phandle of the target of the fixup. +6. For each fixup in the property locate the node:property:offset location + and replace it with the phandle value. diff --git a/drivers/of/Kconfig b/drivers/of/Kconfig index 5160c4eb73c..6b81a36f642 100644 --- a/drivers/of/Kconfig +++ b/drivers/of/Kconfig @@ -79,4 +79,7 @@ config OF_RESERVED_MEM help Helpers to allow for reservation of memory regions +config OF_RESOLVE + bool + endmenu # OF diff --git a/drivers/of/Makefile b/drivers/of/Makefile index 2b6a7b129d1..ca9209ce50c 100644 --- a/drivers/of/Makefile +++ b/drivers/of/Makefile @@ -13,6 +13,7 @@ obj-$(CONFIG_OF_PCI) += of_pci.o obj-$(CONFIG_OF_PCI_IRQ) += of_pci_irq.o obj-$(CONFIG_OF_MTD) += of_mtd.o obj-$(CONFIG_OF_RESERVED_MEM) += of_reserved_mem.o +obj-$(CONFIG_OF_RESOLVE) += resolver.o CFLAGS_fdt.o = -I$(src)/../../scripts/dtc/libfdt CFLAGS_fdt_address.o = -I$(src)/../../scripts/dtc/libfdt diff --git a/drivers/of/resolver.c b/drivers/of/resolver.c new file mode 100644 index 00000000000..aed7959f800 --- /dev/null +++ b/drivers/of/resolver.c @@ -0,0 +1,336 @@ +/* + * Functions for dealing with DT resolution + * + * Copyright (C) 2012 Pantelis Antoniou + * Copyright (C) 2012 Texas Instruments Inc. + * + * 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. + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include + +/* illegal phandle value (set when unresolved) */ +#define OF_PHANDLE_ILLEGAL 0xdeadbeef + +/** + * Find a node with the give full name by recursively following any of + * the child node links. + */ +static struct device_node *__of_find_node_by_full_name(struct device_node *node, + const char *full_name) +{ + struct device_node *child, *found; + + if (node == NULL) + return NULL; + + /* check */ + if (of_node_cmp(node->full_name, full_name) == 0) + return node; + + for_each_child_of_node(node, child) { + found = __of_find_node_by_full_name(child, full_name); + if (found != NULL) + return found; + } + + return NULL; +} + +/* + * Find live tree's maximum phandle value. + */ +static phandle of_get_tree_max_phandle(void) +{ + struct device_node *node; + phandle phandle; + unsigned long flags; + + /* now search recursively */ + raw_spin_lock_irqsave(&devtree_lock, flags); + phandle = 0; + for_each_of_allnodes(node) { + if (node->phandle != OF_PHANDLE_ILLEGAL && + node->phandle > phandle) + phandle = node->phandle; + } + raw_spin_unlock_irqrestore(&devtree_lock, flags); + + return phandle; +} + +/* + * Adjust a subtree's phandle values by a given delta. + * Makes sure not to just adjust the device node's phandle value, + * but modify the phandle properties values as well. + */ +static void __of_adjust_tree_phandles(struct device_node *node, + int phandle_delta) +{ + struct device_node *child; + struct property *prop; + phandle phandle; + + /* first adjust the node's phandle direct value */ + if (node->phandle != 0 && node->phandle != OF_PHANDLE_ILLEGAL) + node->phandle += phandle_delta; + + /* now adjust phandle & linux,phandle values */ + for_each_property_of_node(node, prop) { + + /* only look for these two */ + if (of_prop_cmp(prop->name, "phandle") != 0 && + of_prop_cmp(prop->name, "linux,phandle") != 0) + continue; + + /* must be big enough */ + if (prop->length < 4) + continue; + + /* read phandle value */ + phandle = be32_to_cpup(prop->value); + if (phandle == OF_PHANDLE_ILLEGAL) /* unresolved */ + continue; + + /* adjust */ + *(uint32_t *)prop->value = cpu_to_be32(node->phandle); + } + + /* now do the children recursively */ + for_each_child_of_node(node, child) + __of_adjust_tree_phandles(child, phandle_delta); +} + +static int __of_adjust_phandle_ref(struct device_node *node, struct property *rprop, int value, bool is_delta) +{ + phandle phandle; + struct device_node *refnode; + struct property *sprop; + char *propval, *propcur, *propend, *nodestr, *propstr, *s; + int offset, propcurlen; + int err = 0; + + /* make a copy */ + propval = kmalloc(rprop->length, GFP_KERNEL); + if (!propval) { + pr_err("%s: Could not copy value of '%s'\n", + __func__, rprop->name); + return -ENOMEM; + } + memcpy(propval, rprop->value, rprop->length); + + propend = propval + rprop->length; + for (propcur = propval; propcur < propend; propcur += propcurlen + 1) { + propcurlen = strlen(propcur); + + nodestr = propcur; + s = strchr(propcur, ':'); + if (!s) { + pr_err("%s: Illegal symbol entry '%s' (1)\n", + __func__, propcur); + err = -EINVAL; + goto err_fail; + } + *s++ = '\0'; + + propstr = s; + s = strchr(s, ':'); + if (!s) { + pr_err("%s: Illegal symbol entry '%s' (2)\n", + __func__, (char *)rprop->value); + err = -EINVAL; + goto err_fail; + } + + *s++ = '\0'; + err = kstrtoint(s, 10, &offset); + if (err != 0) { + pr_err("%s: Could get offset '%s'\n", + __func__, (char *)rprop->value); + goto err_fail; + } + + /* look into the resolve node for the full path */ + refnode = __of_find_node_by_full_name(node, nodestr); + if (!refnode) { + pr_warn("%s: Could not find refnode '%s'\n", + __func__, (char *)rprop->value); + continue; + } + + /* now find the property */ + for_each_property_of_node(refnode, sprop) { + if (of_prop_cmp(sprop->name, propstr) == 0) + break; + } + + if (!sprop) { + pr_err("%s: Could not find property '%s'\n", + __func__, (char *)rprop->value); + err = -ENOENT; + goto err_fail; + } + + phandle = is_delta ? be32_to_cpup(sprop->value + offset) + value : value; + *(__be32 *)(sprop->value + offset) = cpu_to_be32(phandle); + } + +err_fail: + kfree(propval); + return err; +} + +/* + * Adjust the local phandle references by the given phandle delta. + * Assumes the existances of a __local_fixups__ node at the root + * of the tree. Does not take any devtree locks so make sure you + * call this on a tree which is at the detached state. + */ +static int __of_adjust_tree_phandle_references(struct device_node *node, + int phandle_delta) +{ + struct device_node *child; + struct property *rprop; + int err; + + /* locate the symbols & fixups nodes on resolve */ + for_each_child_of_node(node, child) + if (of_node_cmp(child->name, "__local_fixups__") == 0) + break; + + /* no local fixups */ + if (!child) + return 0; + + /* find the local fixups property */ + for_each_property_of_node(child, rprop) { + /* skip properties added automatically */ + if (of_prop_cmp(rprop->name, "name") == 0) + continue; + + err = __of_adjust_phandle_ref(node, rprop, phandle_delta, true); + if (err) + return err; + } + + return 0; +} + +/** + * of_resolve - Resolve the given node against the live tree. + * + * @resolve: Node to resolve + * + * Perform dynamic Device Tree resolution against the live tree + * to the given node to resolve. This depends on the live tree + * having a __symbols__ node, and the resolve node the __fixups__ & + * __local_fixups__ nodes (if needed). + * The result of the operation is a resolve node that it's contents + * are fit to be inserted or operate upon the live tree. + * Returns 0 on success or a negative error value on error. + */ +int of_resolve_phandles(struct device_node *resolve) +{ + struct device_node *child, *refnode; + struct device_node *root_sym, *resolve_sym, *resolve_fix; + struct property *rprop; + const char *refpath; + phandle phandle, phandle_delta; + int err; + + /* the resolve node must exist, and be detached */ + if (!resolve || !of_node_check_flag(resolve, OF_DETACHED)) + return -EINVAL; + + /* first we need to adjust the phandles */ + phandle_delta = of_get_tree_max_phandle() + 1; + __of_adjust_tree_phandles(resolve, phandle_delta); + err = __of_adjust_tree_phandle_references(resolve, phandle_delta); + if (err != 0) + return err; + + root_sym = NULL; + resolve_sym = NULL; + resolve_fix = NULL; + + /* this may fail (if no fixups are required) */ + root_sym = of_find_node_by_path("/__symbols__"); + + /* locate the symbols & fixups nodes on resolve */ + for_each_child_of_node(resolve, child) { + + if (!resolve_sym && + of_node_cmp(child->name, "__symbols__") == 0) + resolve_sym = child; + + if (!resolve_fix && + of_node_cmp(child->name, "__fixups__") == 0) + resolve_fix = child; + + /* both found, don't bother anymore */ + if (resolve_sym && resolve_fix) + break; + } + + /* we do allow for the case where no fixups are needed */ + if (!resolve_fix) { + err = 0; /* no error */ + goto out; + } + + /* we need to fixup, but no root symbols... */ + if (!root_sym) { + err = -EINVAL; + goto out; + } + + for_each_property_of_node(resolve_fix, rprop) { + + /* skip properties added automatically */ + if (of_prop_cmp(rprop->name, "name") == 0) + continue; + + err = of_property_read_string(root_sym, + rprop->name, &refpath); + if (err != 0) { + pr_err("%s: Could not find symbol '%s'\n", + __func__, rprop->name); + goto out; + } + + refnode = of_find_node_by_path(refpath); + if (!refnode) { + pr_err("%s: Could not find node by path '%s'\n", + __func__, refpath); + err = -ENOENT; + goto out; + } + + phandle = refnode->phandle; + of_node_put(refnode); + + pr_debug("%s: %s phandle is 0x%08x\n", + __func__, rprop->name, phandle); + + err = __of_adjust_phandle_ref(resolve, rprop, phandle, false); + if (err) + break; + } + +out: + /* NULL is handled by of_node_put as NOP */ + of_node_put(root_sym); + + return err; +} +EXPORT_SYMBOL_GPL(of_resolve_phandles); diff --git a/include/linux/of.h b/include/linux/of.h index 6c4363b8ddc..6545e7aec7b 100644 --- a/include/linux/of.h +++ b/include/linux/of.h @@ -863,4 +863,7 @@ static inline int of_changeset_update_property(struct of_changeset *ocs, } #endif +/* CONFIG_OF_RESOLVE api */ +extern int of_resolve_phandles(struct device_node *tree); + #endif /* _LINUX_OF_H */ -- cgit v1.2.3-70-g09d2 From a87fa1d81a9fb5e9adca9820e16008c40ad09f33 Mon Sep 17 00:00:00 2001 From: Grant Likely Date: Mon, 3 Nov 2014 15:15:35 +0000 Subject: of: Fix overflow bug in string property parsing functions The string property read helpers will run off the end of the buffer if it is handed a malformed string property. Rework the parsers to make sure that doesn't happen. At the same time add new test cases to make sure the functions behave themselves. The original implementations of of_property_read_string_index() and of_property_count_strings() both open-coded the same block of parsing code, each with it's own subtly different bugs. The fix here merges functions into a single helper and makes the original functions static inline wrappers around the helper. One non-bugfix aspect of this patch is the addition of a new wrapper, of_property_read_string_array(). The new wrapper is needed by the device_properties feature that Rafael is working on and planning to merge for v3.19. The implementation is identical both with and without the new static inline wrapper, so it just got left in to reduce the churn on the header file. Signed-off-by: Grant Likely Cc: Rafael J. Wysocki Cc: Mika Westerberg Cc: Rob Herring Cc: Arnd Bergmann Cc: Darren Hart Cc: # v3.3+: Drop selftest hunks that don't apply --- drivers/of/base.c | 88 ++++++++--------------------- drivers/of/selftest.c | 66 ++++++++++++++++++++-- drivers/of/testcase-data/tests-phandle.dtsi | 2 + include/linux/of.h | 84 ++++++++++++++++++++++----- 4 files changed, 154 insertions(+), 86 deletions(-) (limited to 'include/linux/of.h') diff --git a/drivers/of/base.c b/drivers/of/base.c index 2305dc0382b..3823edf2d01 100644 --- a/drivers/of/base.c +++ b/drivers/of/base.c @@ -1279,52 +1279,6 @@ int of_property_read_string(struct device_node *np, const char *propname, } EXPORT_SYMBOL_GPL(of_property_read_string); -/** - * of_property_read_string_index - Find and read a string from a multiple - * strings property. - * @np: device node from which the property value is to be read. - * @propname: name of the property to be searched. - * @index: index of the string in the list of strings - * @out_string: pointer to null terminated return string, modified only if - * return value is 0. - * - * Search for a property in a device tree node and retrieve a null - * terminated string value (pointer to data, not a copy) in the list of strings - * contained in that property. - * Returns 0 on success, -EINVAL if the property does not exist, -ENODATA if - * property does not have a value, and -EILSEQ if the string is not - * null-terminated within the length of the property data. - * - * The out_string pointer is modified only if a valid string can be decoded. - */ -int of_property_read_string_index(struct device_node *np, const char *propname, - int index, const char **output) -{ - struct property *prop = of_find_property(np, propname, NULL); - int i = 0; - size_t l = 0, total = 0; - const char *p; - - if (!prop) - return -EINVAL; - if (!prop->value) - return -ENODATA; - if (strnlen(prop->value, prop->length) >= prop->length) - return -EILSEQ; - - p = prop->value; - - for (i = 0; total < prop->length; total += l, p += l) { - l = strlen(p) + 1; - if (i++ == index) { - *output = p; - return 0; - } - } - return -ENODATA; -} -EXPORT_SYMBOL_GPL(of_property_read_string_index); - /** * of_property_match_string() - Find string in a list and return index * @np: pointer to node containing string list property @@ -1351,7 +1305,7 @@ int of_property_match_string(struct device_node *np, const char *propname, end = p + prop->length; for (i = 0; p < end; i++, p += l) { - l = strlen(p) + 1; + l = strnlen(p, end - p) + 1; if (p + l > end) return -EILSEQ; pr_debug("comparing %s with %s\n", string, p); @@ -1363,39 +1317,41 @@ int of_property_match_string(struct device_node *np, const char *propname, EXPORT_SYMBOL_GPL(of_property_match_string); /** - * of_property_count_strings - Find and return the number of strings from a - * multiple strings property. + * of_property_read_string_util() - Utility helper for parsing string properties * @np: device node from which the property value is to be read. * @propname: name of the property to be searched. + * @out_strs: output array of string pointers. + * @sz: number of array elements to read. + * @skip: Number of strings to skip over at beginning of list. * - * Search for a property in a device tree node and retrieve the number of null - * terminated string contain in it. Returns the number of strings on - * success, -EINVAL if the property does not exist, -ENODATA if property - * does not have a value, and -EILSEQ if the string is not null-terminated - * within the length of the property data. + * Don't call this function directly. It is a utility helper for the + * of_property_read_string*() family of functions. */ -int of_property_count_strings(struct device_node *np, const char *propname) +int of_property_read_string_helper(struct device_node *np, const char *propname, + const char **out_strs, size_t sz, int skip) { struct property *prop = of_find_property(np, propname, NULL); - int i = 0; - size_t l = 0, total = 0; - const char *p; + int l = 0, i = 0; + const char *p, *end; if (!prop) return -EINVAL; if (!prop->value) return -ENODATA; - if (strnlen(prop->value, prop->length) >= prop->length) - return -EILSEQ; - p = prop->value; + end = p + prop->length; - for (i = 0; total < prop->length; total += l, p += l, i++) - l = strlen(p) + 1; - - return i; + for (i = 0; p < end && (!out_strs || i < skip + sz); i++, p += l) { + l = strnlen(p, end - p) + 1; + if (p + l > end) + return -EILSEQ; + if (out_strs && i >= skip) + *out_strs++ = p; + } + i -= skip; + return i <= 0 ? -ENODATA : i; } -EXPORT_SYMBOL_GPL(of_property_count_strings); +EXPORT_SYMBOL_GPL(of_property_read_string_helper); void of_print_phandle_args(const char *msg, const struct of_phandle_args *args) { diff --git a/drivers/of/selftest.c b/drivers/of/selftest.c index 78001270a59..11b873c54a7 100644 --- a/drivers/of/selftest.c +++ b/drivers/of/selftest.c @@ -339,8 +339,9 @@ static void __init of_selftest_parse_phandle_with_args(void) selftest(rc == -EINVAL, "expected:%i got:%i\n", -EINVAL, rc); } -static void __init of_selftest_property_match_string(void) +static void __init of_selftest_property_string(void) { + const char *strings[4]; struct device_node *np; int rc; @@ -357,13 +358,66 @@ static void __init of_selftest_property_match_string(void) rc = of_property_match_string(np, "phandle-list-names", "third"); selftest(rc == 2, "third expected:0 got:%i\n", rc); rc = of_property_match_string(np, "phandle-list-names", "fourth"); - selftest(rc == -ENODATA, "unmatched string; rc=%i", rc); + selftest(rc == -ENODATA, "unmatched string; rc=%i\n", rc); rc = of_property_match_string(np, "missing-property", "blah"); - selftest(rc == -EINVAL, "missing property; rc=%i", rc); + selftest(rc == -EINVAL, "missing property; rc=%i\n", rc); rc = of_property_match_string(np, "empty-property", "blah"); - selftest(rc == -ENODATA, "empty property; rc=%i", rc); + selftest(rc == -ENODATA, "empty property; rc=%i\n", rc); rc = of_property_match_string(np, "unterminated-string", "blah"); - selftest(rc == -EILSEQ, "unterminated string; rc=%i", rc); + selftest(rc == -EILSEQ, "unterminated string; rc=%i\n", rc); + + /* of_property_count_strings() tests */ + rc = of_property_count_strings(np, "string-property"); + selftest(rc == 1, "Incorrect string count; rc=%i\n", rc); + rc = of_property_count_strings(np, "phandle-list-names"); + selftest(rc == 3, "Incorrect string count; rc=%i\n", rc); + rc = of_property_count_strings(np, "unterminated-string"); + selftest(rc == -EILSEQ, "unterminated string; rc=%i\n", rc); + rc = of_property_count_strings(np, "unterminated-string-list"); + selftest(rc == -EILSEQ, "unterminated string array; rc=%i\n", rc); + + /* of_property_read_string_index() tests */ + rc = of_property_read_string_index(np, "string-property", 0, strings); + selftest(rc == 0 && !strcmp(strings[0], "foobar"), "of_property_read_string_index() failure; rc=%i\n", rc); + strings[0] = NULL; + rc = of_property_read_string_index(np, "string-property", 1, strings); + selftest(rc == -ENODATA && strings[0] == NULL, "of_property_read_string_index() failure; rc=%i\n", rc); + rc = of_property_read_string_index(np, "phandle-list-names", 0, strings); + selftest(rc == 0 && !strcmp(strings[0], "first"), "of_property_read_string_index() failure; rc=%i\n", rc); + rc = of_property_read_string_index(np, "phandle-list-names", 1, strings); + selftest(rc == 0 && !strcmp(strings[0], "second"), "of_property_read_string_index() failure; rc=%i\n", rc); + rc = of_property_read_string_index(np, "phandle-list-names", 2, strings); + selftest(rc == 0 && !strcmp(strings[0], "third"), "of_property_read_string_index() failure; rc=%i\n", rc); + strings[0] = NULL; + rc = of_property_read_string_index(np, "phandle-list-names", 3, strings); + selftest(rc == -ENODATA && strings[0] == NULL, "of_property_read_string_index() failure; rc=%i\n", rc); + strings[0] = NULL; + rc = of_property_read_string_index(np, "unterminated-string", 0, strings); + selftest(rc == -EILSEQ && strings[0] == NULL, "of_property_read_string_index() failure; rc=%i\n", rc); + rc = of_property_read_string_index(np, "unterminated-string-list", 0, strings); + selftest(rc == 0 && !strcmp(strings[0], "first"), "of_property_read_string_index() failure; rc=%i\n", rc); + strings[0] = NULL; + rc = of_property_read_string_index(np, "unterminated-string-list", 2, strings); /* should fail */ + selftest(rc == -EILSEQ && strings[0] == NULL, "of_property_read_string_index() failure; rc=%i\n", rc); + strings[1] = NULL; + + /* of_property_read_string_array() tests */ + rc = of_property_read_string_array(np, "string-property", strings, 4); + selftest(rc == 1, "Incorrect string count; rc=%i\n", rc); + rc = of_property_read_string_array(np, "phandle-list-names", strings, 4); + selftest(rc == 3, "Incorrect string count; rc=%i\n", rc); + rc = of_property_read_string_array(np, "unterminated-string", strings, 4); + selftest(rc == -EILSEQ, "unterminated string; rc=%i\n", rc); + /* -- An incorrectly formed string should cause a failure */ + rc = of_property_read_string_array(np, "unterminated-string-list", strings, 4); + selftest(rc == -EILSEQ, "unterminated string array; rc=%i\n", rc); + /* -- parsing the correctly formed strings should still work: */ + strings[2] = NULL; + rc = of_property_read_string_array(np, "unterminated-string-list", strings, 2); + selftest(rc == 2 && strings[2] == NULL, "of_property_read_string_array() failure; rc=%i\n", rc); + strings[1] = NULL; + rc = of_property_read_string_array(np, "phandle-list-names", strings, 1); + selftest(rc == 1 && strings[1] == NULL, "Overwrote end of string array; rc=%i, str='%s'\n", rc, strings[1]); } #define propcmp(p1, p2) (((p1)->length == (p2)->length) && \ @@ -881,7 +935,7 @@ static int __init of_selftest(void) of_selftest_find_node_by_name(); of_selftest_dynamic(); of_selftest_parse_phandle_with_args(); - of_selftest_property_match_string(); + of_selftest_property_string(); of_selftest_property_copy(); of_selftest_changeset(); of_selftest_parse_interrupts(); diff --git a/drivers/of/testcase-data/tests-phandle.dtsi b/drivers/of/testcase-data/tests-phandle.dtsi index ce0fe083d40..5b1527e8a7f 100644 --- a/drivers/of/testcase-data/tests-phandle.dtsi +++ b/drivers/of/testcase-data/tests-phandle.dtsi @@ -39,7 +39,9 @@ phandle-list-bad-args = <&provider2 1 0>, <&provider3 0>; empty-property; + string-property = "foobar"; unterminated-string = [40 41 42 43]; + unterminated-string-list = "first", "second", [40 41 42 43]; }; }; }; diff --git a/include/linux/of.h b/include/linux/of.h index 6545e7aec7b..29f0adc5f3e 100644 --- a/include/linux/of.h +++ b/include/linux/of.h @@ -267,14 +267,12 @@ extern int of_property_read_u64(const struct device_node *np, extern int of_property_read_string(struct device_node *np, const char *propname, const char **out_string); -extern int of_property_read_string_index(struct device_node *np, - const char *propname, - int index, const char **output); extern int of_property_match_string(struct device_node *np, const char *propname, const char *string); -extern int of_property_count_strings(struct device_node *np, - const char *propname); +extern int of_property_read_string_helper(struct device_node *np, + const char *propname, + const char **out_strs, size_t sz, int index); extern int of_device_is_compatible(const struct device_node *device, const char *); extern int of_device_is_available(const struct device_node *device); @@ -486,15 +484,9 @@ static inline int of_property_read_string(struct device_node *np, return -ENOSYS; } -static inline int of_property_read_string_index(struct device_node *np, - const char *propname, int index, - const char **out_string) -{ - return -ENOSYS; -} - -static inline int of_property_count_strings(struct device_node *np, - const char *propname) +static inline int of_property_read_string_helper(struct device_node *np, + const char *propname, + const char **out_strs, size_t sz, int index) { return -ENOSYS; } @@ -667,6 +659,70 @@ static inline int of_property_count_u64_elems(const struct device_node *np, return of_property_count_elems_of_size(np, propname, sizeof(u64)); } +/** + * of_property_read_string_array() - Read an array of strings from a multiple + * strings property. + * @np: device node from which the property value is to be read. + * @propname: name of the property to be searched. + * @out_strs: output array of string pointers. + * @sz: number of array elements to read. + * + * Search for a property in a device tree node and retrieve a list of + * terminated string values (pointer to data, not a copy) in that property. + * + * If @out_strs is NULL, the number of strings in the property is returned. + */ +static inline int of_property_read_string_array(struct device_node *np, + const char *propname, const char **out_strs, + size_t sz) +{ + return of_property_read_string_helper(np, propname, out_strs, sz, 0); +} + +/** + * of_property_count_strings() - Find and return the number of strings from a + * multiple strings property. + * @np: device node from which the property value is to be read. + * @propname: name of the property to be searched. + * + * Search for a property in a device tree node and retrieve the number of null + * terminated string contain in it. Returns the number of strings on + * success, -EINVAL if the property does not exist, -ENODATA if property + * does not have a value, and -EILSEQ if the string is not null-terminated + * within the length of the property data. + */ +static inline int of_property_count_strings(struct device_node *np, + const char *propname) +{ + return of_property_read_string_helper(np, propname, NULL, 0, 0); +} + +/** + * of_property_read_string_index() - Find and read a string from a multiple + * strings property. + * @np: device node from which the property value is to be read. + * @propname: name of the property to be searched. + * @index: index of the string in the list of strings + * @out_string: pointer to null terminated return string, modified only if + * return value is 0. + * + * Search for a property in a device tree node and retrieve a null + * terminated string value (pointer to data, not a copy) in the list of strings + * contained in that property. + * Returns 0 on success, -EINVAL if the property does not exist, -ENODATA if + * property does not have a value, and -EILSEQ if the string is not + * null-terminated within the length of the property data. + * + * The out_string pointer is modified only if a valid string can be decoded. + */ +static inline int of_property_read_string_index(struct device_node *np, + const char *propname, + int index, const char **output) +{ + int rc = of_property_read_string_helper(np, propname, output, 1, index); + return rc < 0 ? rc : 0; +} + /** * of_property_read_bool - Findfrom a property * @np: device node from which the property value is to be read. -- cgit v1.2.3-70-g09d2